This document describes the modeling and analysis of a steel lattice roof structure. It includes the modeling process from the initial sizing of structural elements, applying loads and constraints, performing analyses, and verifying results. Various load cases are considered representing self-weight, snow, and wind loads. Initial member sizing is performed through simplified calculations and iteratively updated based on the calculated self-weight. Finite element analysis is used to analyze the fully modeled structure and check stresses and reactions. Design verifications are also presented to check member capacities.
Cases of eccentric loading in bolted jointsvaibhav tailor
This document summarizes the design methodology for joints subjected to eccentric loading for three types: screwed, riveted, and welded joints. For screwed joints, additional equations beyond statics are needed to solve for tensions in the screws since the load causes rotation. Forces are proportional to distance from the rotation point. For riveted joints, additional shear forces appear proportional to distance from the centroid, with direction perpendicular to the line between centroid and rivet. Net forces are found using vector addition. For both, maximum stress must be below allowable to ensure safe design.
This presentation discusses the design of cast iron pulleys. It begins by introducing cast iron pulleys and their typical construction with a rim held by arms or spokes connected to a central boss. The presentation notes that cast iron pulleys are made of grey cast iron and the rim and arms are typically steel. It then discusses features like crowning, which keeps the belt centered, and split pulleys, which allow mounting on an existing shaft. The presentation concludes by providing formulas for calculating torque transmission and determining the required elliptical cross-section of arms, using an example of a 500mm pulley transmitting 10kW of power.
This document discusses hoisting and dynamics of rotation. It provides examples and explanations of:
1) The forces, torques, and equations of motion involved when a hoist drum raises or lowers a load while accelerating or decelerating. This includes the inertia couple of the drum opposing changes in rotation and friction torque opposing rotation.
2) Specific examples that calculate the torque required to raise a load or bring it to a stop, given information like the drum's moment of inertia, load mass, acceleration, and friction torque.
3) Diagrams illustrate the forces and torques acting on the hoist drum and load in different scenarios like raising or lowering while accelerating versus coming to a stop
The document describes a torsion testing experiment. The objectives are to:
1. Determine the shear modulus (G) of different materials and the relationship between applied torque and angular twist.
2. Examine how material length affects angular twist.
The experiment involves twisting steel and brass rods of different lengths using known torques and measuring the angular deflection. Graphs of the data are used to calculate G, finding values of 68.46 GPa for steel and 38.8 GPa for brass, which are close to reference values. Testing another brass rod of varying lengths, a graph shows angular twist increases proportionally with length. G is recalculated from this graph as 43.50 GPa
This document describes a C++ program for linear analysis of a 2D truss. The program calculates member forces and displacements. The results are verified using the structural analysis program SAP2000. The program includes input of truss geometry and properties, calculation of the global stiffness matrix and displacements, and output of member forces. Figures show the truss model in the C++ program, output from the program, and verification of results using SAP2000 modeling and analysis.
This document provides a summary of revisions made to the Zamil Steel Company Limited Pre-Engineered Buildings Division Design Manual. Some of the major changes included in this revision relate to:
- Serviceability consideration requirements
- Expansion joint standards
- Bracing system arrangement guidelines
- Standards for built-up sections, galvanized members, and standard anchor bolts
- Updates to the design of various structural components like flange braces, crane beams, roof and wall framing members, and end wall systems
The document outlines the responsibilities of design and quote engineers and provides the table of contents for the manual, which covers topics like materials, loads, framing design, secondary member design, and end wall
Finite element analysis of center pin and bracket of jig fixture assembly ijm...Dr.Vikas Deulgaonkar
The manufacturing industry caters the range of products to satisfy the ever changing market needs.
To overcome the increasing production demands, the industry implies various techniques. We need a technique for
increasing the production of drilling two holes on a Railway Pinion, improve the quality of product and reduce the
operation time. This project aims to design the Jig and Fixture for the same. The 3-dimensional Computer Aided Model
of the components is made using CATIA V5-R21 software. To study the behavior of component, simulation is carried out.
Preprocessing of the CAD model is carried in Hypermesh software. Boundary conditions are applied using physical
situations of the components. Finite element analysis of the components is done, and the results obtained are compared
with the theoretical analysis and also with the available literature. The stresses and deformations are found within desired limits. Using FE analysis, the parts are manufactured and assembled.
1) The document discusses the design of shafts subjected to different loading conditions including bending, torsion, combined bending and torsion, fluctuating loads, and axial loads.
2) Formulas are provided to calculate the equivalent bending moment and equivalent twisting moment for shafts under various loading conditions.
3) Examples are presented to demonstrate how to use the formulas and determine the necessary shaft diameter based on allowable stresses.
Cases of eccentric loading in bolted jointsvaibhav tailor
This document summarizes the design methodology for joints subjected to eccentric loading for three types: screwed, riveted, and welded joints. For screwed joints, additional equations beyond statics are needed to solve for tensions in the screws since the load causes rotation. Forces are proportional to distance from the rotation point. For riveted joints, additional shear forces appear proportional to distance from the centroid, with direction perpendicular to the line between centroid and rivet. Net forces are found using vector addition. For both, maximum stress must be below allowable to ensure safe design.
This presentation discusses the design of cast iron pulleys. It begins by introducing cast iron pulleys and their typical construction with a rim held by arms or spokes connected to a central boss. The presentation notes that cast iron pulleys are made of grey cast iron and the rim and arms are typically steel. It then discusses features like crowning, which keeps the belt centered, and split pulleys, which allow mounting on an existing shaft. The presentation concludes by providing formulas for calculating torque transmission and determining the required elliptical cross-section of arms, using an example of a 500mm pulley transmitting 10kW of power.
This document discusses hoisting and dynamics of rotation. It provides examples and explanations of:
1) The forces, torques, and equations of motion involved when a hoist drum raises or lowers a load while accelerating or decelerating. This includes the inertia couple of the drum opposing changes in rotation and friction torque opposing rotation.
2) Specific examples that calculate the torque required to raise a load or bring it to a stop, given information like the drum's moment of inertia, load mass, acceleration, and friction torque.
3) Diagrams illustrate the forces and torques acting on the hoist drum and load in different scenarios like raising or lowering while accelerating versus coming to a stop
The document describes a torsion testing experiment. The objectives are to:
1. Determine the shear modulus (G) of different materials and the relationship between applied torque and angular twist.
2. Examine how material length affects angular twist.
The experiment involves twisting steel and brass rods of different lengths using known torques and measuring the angular deflection. Graphs of the data are used to calculate G, finding values of 68.46 GPa for steel and 38.8 GPa for brass, which are close to reference values. Testing another brass rod of varying lengths, a graph shows angular twist increases proportionally with length. G is recalculated from this graph as 43.50 GPa
This document describes a C++ program for linear analysis of a 2D truss. The program calculates member forces and displacements. The results are verified using the structural analysis program SAP2000. The program includes input of truss geometry and properties, calculation of the global stiffness matrix and displacements, and output of member forces. Figures show the truss model in the C++ program, output from the program, and verification of results using SAP2000 modeling and analysis.
This document provides a summary of revisions made to the Zamil Steel Company Limited Pre-Engineered Buildings Division Design Manual. Some of the major changes included in this revision relate to:
- Serviceability consideration requirements
- Expansion joint standards
- Bracing system arrangement guidelines
- Standards for built-up sections, galvanized members, and standard anchor bolts
- Updates to the design of various structural components like flange braces, crane beams, roof and wall framing members, and end wall systems
The document outlines the responsibilities of design and quote engineers and provides the table of contents for the manual, which covers topics like materials, loads, framing design, secondary member design, and end wall
Finite element analysis of center pin and bracket of jig fixture assembly ijm...Dr.Vikas Deulgaonkar
The manufacturing industry caters the range of products to satisfy the ever changing market needs.
To overcome the increasing production demands, the industry implies various techniques. We need a technique for
increasing the production of drilling two holes on a Railway Pinion, improve the quality of product and reduce the
operation time. This project aims to design the Jig and Fixture for the same. The 3-dimensional Computer Aided Model
of the components is made using CATIA V5-R21 software. To study the behavior of component, simulation is carried out.
Preprocessing of the CAD model is carried in Hypermesh software. Boundary conditions are applied using physical
situations of the components. Finite element analysis of the components is done, and the results obtained are compared
with the theoretical analysis and also with the available literature. The stresses and deformations are found within desired limits. Using FE analysis, the parts are manufactured and assembled.
1) The document discusses the design of shafts subjected to different loading conditions including bending, torsion, combined bending and torsion, fluctuating loads, and axial loads.
2) Formulas are provided to calculate the equivalent bending moment and equivalent twisting moment for shafts under various loading conditions.
3) Examples are presented to demonstrate how to use the formulas and determine the necessary shaft diameter based on allowable stresses.
This document discusses threaded fasteners and screw threads. It defines common screw thread parameters like pitch, major diameter, and thread angle. It describes metric and unified screw thread standards. It also discusses power screws, different types of threaded fasteners, and how to select the proper fastener for an application based on required load and functional parameters.
This document summarizes the assumptions and limitations of the steel frame design algorithms in the software for Eurocode 3-2005. Some key assumptions include using the CEN version of the code by default, assuming plastic design for shear resistance, and ignoring intermediate shear stiffeners. Limitations include an inability to design sections under 3mm thick or consider the effects of torsion, high-strength steels, or circular hollow sections. The user is advised to review all assumptions and limitations.
The document contains 6 numerical problems related to calculating stresses, moments of inertia, and section moduli for beams and shafts with various cross-sectional geometries under different loading conditions. Solutions are provided for rectangular, circular, square, and hollow cross-sections. Bending stresses, axial stresses, radii of curvature, and polar moments of inertia are calculated using relevant stress and bending formulas.
1. The document provides formulas for calculating slope, deflection, and maximum deflection for various beam types under different loading conditions. It gives the equations for cantilever beams with concentrated loads, uniformly distributed loads, and varying loads. It also provides the equations for simply supported beams with these different load types and with couple moments applied. The equations relate the beam properties like length, load location, and intensity to the resulting slope and deflection values.
1) The document discusses various loading mechanisms that act on shafts, including loads from gears, belts, chains, and unbalanced masses. It also covers stresses in shafts such as bending, torsional, and axial stresses due to different loads.
2) Formulas are presented for calculating loads and stresses on shafts from common mechanical components like gears, belts, and chains. Examples of engineering problems are also given to calculate forces and loads on rotating shafts.
3) Rotating shafts are complex mechanical elements that experience many different types of loads that must be properly analyzed and accounted for in shaft design.
08-Strength of Welded Connections (Steel Structural Design & Prof. Shehab Mou...Hossam Shafiq II
The document discusses the strength of welded connections, including fillet and groove welds. It provides the equations to calculate the strength of fillet welds based on weld size and length. It also provides equations for calculating the strength of gusset plates based on yield strength, tensile strength, and area. An example calculation is shown for a welded connection with longitudinal and transverse welds. The strength is calculated for the welds, angles, and gusset plate. The governing strength is found to be the yielding of the gusset plate at 457.2 kN.
This document describes the design of a worm and worm wheel gear set. It begins with an introduction to worm gears and their applications where fast braking, low noise, or space constraints are important factors. The document then outlines the design process, which involves selecting design parameters like tooth count and lead angle, calculating loads, strength, and efficiency. The design problem provided is to transmit 22 kW between shafts 225 mm apart with a 24:1 transmission ratio using phosphor bronze materials. The document details the step-by-step design process to solve this problem and size the worm and worm wheel gears.
This document discusses a mini project on a four bar linkage mechanism. A four bar linkage consists of four links connected by four pin joints to form a quadrilateral. It includes a fixed link, connecting link, crank link, and rocker link. The crank rotates due to the rotation of a driving wheel and transmits motion to the connecting rod. The connecting rod then transmits oscillating motion to the rocker arm. Four bar linkages have many applications such as in deep boring machines, locomotives, hand pumps, and lathes.
The document is a final project report for the design of a double branch double reduction gearbox for a solar-powered aircraft. It details the design process undertaken by the NikolaDrive team to meet requirements of minimizing weight, maximizing efficiency, and enduring the aircraft's lifetime. The team designed gears, shafts, and bearings integrated using a safety factor of 1.5. All components were iterated until falling within this safety factor. The total system operates at less than 5% power loss and weighs 14.4 kg, exceeding the 5.5 kg target weight. Individual contributions of the three team members to the overall collaborative effort are outlined.
Unit 5 Design of Threaded and Welded JointsMahesh Shinde
1) The document discusses different types of threaded and welded joints. It describes various threaded fasteners like bolts, studs, screws and their characteristics.
2) For threaded joints subjected to eccentric loads, it explains how to calculate the primary and secondary shear forces on each bolt. This involves finding the center of gravity of the bolt system and determining the forces based on the load direction.
3) Sample problems are included to demonstrate how to select the bolt size based on the maximum resultant shear force and required factor of safety. Calculations are shown for eccentrically loaded bolted joints with the load in the plane of bolts.
This document describes the design of a vertical screw conveyor. It includes the selection of a JHS400 screw to transport cement vertically over 3.15 meters. A 1.4552 kW motor operating at 1425 rpm is chosen to power the conveyor. Three A-section V-belts running over pulleys with diameters of 125mm and 250mm are selected to transmit power from the motor to the screw. Gears and chains are also included in the drive mechanism with specified transmission ratios. The shaft, keys, bearings and clutch are designed. Material selections are made for the pulleys, V-belts and other components. Dimensions and specifications are provided for each designed part.
This document appears to be a chapter from a mechanical engineering textbook about clutches, brakes, couplings, and flywheels. It includes section outlines, examples, diagrams, and explanations of topics such as clutch and brake types, force analysis, temperature and energy considerations, friction materials, flywheel sizing, and motor characteristics. The overall content focuses on analyzing and designing mechanical components used for transferring motion and controlling speed and torque.
The document discusses balancing of rotating and reciprocating masses. It describes static and dynamic balancing, where static balancing ensures the center of gravity remains stationary during rotation and dynamic balancing ensures the resultant moments are equal to zero. Types of balancing discussed include balancing a single rotating mass with one or two masses in the same or different planes, as well as balancing multiple masses in the same or different planes. Examples provided calculate the magnitude and position of balancing masses given masses, radii of rotation, and angular positions of unbalanced masses.
This document discusses determining the deflection of beams under load. It introduces the concepts of bending moment (M), modulus of elasticity (E), and moment of inertia (I) in determining curvature and deflection. The maximum deflection can be obtained by solving the second order differential equation that governs the elastic curve of the beam, using the boundary conditions of the beam's supports and applying any loads. Examples are provided to demonstrate how to set up and solve the differential equations to find the deflection at any point on beams with various load configurations.
This document provides a tutorial on using Flow Simulation 2012 software. It covers topics such as opening SolidWorks models, creating flow simulation projects, specifying boundary conditions and engineering goals, running calculations, and viewing results through cut plots, surface plots, and other visualization tools. Step-by-step instructions are provided for analyzing examples involving a ball valve, conjugate heat transfer, porous media flow, hydraulic loss determination, drag coefficient calculation, and heat exchanger efficiency.
The document contains solutions to multiple problems involving calculating stresses in beams subjected to bending moments. For problem 4.1, it is determined that the stress at point A is 61.14 MPa (compressive) and at point B is 91.7 MPa (tensile). For problem 4.2, the stresses at points A and B are calculated to be -5.31 GPa and 3.365 GPa, respectively. Problem 4.3 involves calculating the largest bending moment that can be applied to an aluminum beam before yielding, which is determined to be 5.283 KN.m.
The purpose of this project is to compare the Normal Stresses induced in the Knuckle-Joint due to application of Tensile Force of 12KN by manual calculations and using Ansys Workbench. Also, to find minimum and maximum stress and Deformation in the Joint. In this report, Stresses found analytically are compared with the stresses found by the Analysis Software.
This document discusses threaded fasteners and screw threads. It defines common screw thread parameters like pitch, major diameter, and thread angle. It describes metric and unified screw thread standards. It also discusses power screws, different types of threaded fasteners, and how to select the proper fastener for an application based on required load and functional parameters.
This document summarizes the assumptions and limitations of the steel frame design algorithms in the software for Eurocode 3-2005. Some key assumptions include using the CEN version of the code by default, assuming plastic design for shear resistance, and ignoring intermediate shear stiffeners. Limitations include an inability to design sections under 3mm thick or consider the effects of torsion, high-strength steels, or circular hollow sections. The user is advised to review all assumptions and limitations.
The document contains 6 numerical problems related to calculating stresses, moments of inertia, and section moduli for beams and shafts with various cross-sectional geometries under different loading conditions. Solutions are provided for rectangular, circular, square, and hollow cross-sections. Bending stresses, axial stresses, radii of curvature, and polar moments of inertia are calculated using relevant stress and bending formulas.
1. The document provides formulas for calculating slope, deflection, and maximum deflection for various beam types under different loading conditions. It gives the equations for cantilever beams with concentrated loads, uniformly distributed loads, and varying loads. It also provides the equations for simply supported beams with these different load types and with couple moments applied. The equations relate the beam properties like length, load location, and intensity to the resulting slope and deflection values.
1) The document discusses various loading mechanisms that act on shafts, including loads from gears, belts, chains, and unbalanced masses. It also covers stresses in shafts such as bending, torsional, and axial stresses due to different loads.
2) Formulas are presented for calculating loads and stresses on shafts from common mechanical components like gears, belts, and chains. Examples of engineering problems are also given to calculate forces and loads on rotating shafts.
3) Rotating shafts are complex mechanical elements that experience many different types of loads that must be properly analyzed and accounted for in shaft design.
08-Strength of Welded Connections (Steel Structural Design & Prof. Shehab Mou...Hossam Shafiq II
The document discusses the strength of welded connections, including fillet and groove welds. It provides the equations to calculate the strength of fillet welds based on weld size and length. It also provides equations for calculating the strength of gusset plates based on yield strength, tensile strength, and area. An example calculation is shown for a welded connection with longitudinal and transverse welds. The strength is calculated for the welds, angles, and gusset plate. The governing strength is found to be the yielding of the gusset plate at 457.2 kN.
This document describes the design of a worm and worm wheel gear set. It begins with an introduction to worm gears and their applications where fast braking, low noise, or space constraints are important factors. The document then outlines the design process, which involves selecting design parameters like tooth count and lead angle, calculating loads, strength, and efficiency. The design problem provided is to transmit 22 kW between shafts 225 mm apart with a 24:1 transmission ratio using phosphor bronze materials. The document details the step-by-step design process to solve this problem and size the worm and worm wheel gears.
This document discusses a mini project on a four bar linkage mechanism. A four bar linkage consists of four links connected by four pin joints to form a quadrilateral. It includes a fixed link, connecting link, crank link, and rocker link. The crank rotates due to the rotation of a driving wheel and transmits motion to the connecting rod. The connecting rod then transmits oscillating motion to the rocker arm. Four bar linkages have many applications such as in deep boring machines, locomotives, hand pumps, and lathes.
The document is a final project report for the design of a double branch double reduction gearbox for a solar-powered aircraft. It details the design process undertaken by the NikolaDrive team to meet requirements of minimizing weight, maximizing efficiency, and enduring the aircraft's lifetime. The team designed gears, shafts, and bearings integrated using a safety factor of 1.5. All components were iterated until falling within this safety factor. The total system operates at less than 5% power loss and weighs 14.4 kg, exceeding the 5.5 kg target weight. Individual contributions of the three team members to the overall collaborative effort are outlined.
Unit 5 Design of Threaded and Welded JointsMahesh Shinde
1) The document discusses different types of threaded and welded joints. It describes various threaded fasteners like bolts, studs, screws and their characteristics.
2) For threaded joints subjected to eccentric loads, it explains how to calculate the primary and secondary shear forces on each bolt. This involves finding the center of gravity of the bolt system and determining the forces based on the load direction.
3) Sample problems are included to demonstrate how to select the bolt size based on the maximum resultant shear force and required factor of safety. Calculations are shown for eccentrically loaded bolted joints with the load in the plane of bolts.
This document describes the design of a vertical screw conveyor. It includes the selection of a JHS400 screw to transport cement vertically over 3.15 meters. A 1.4552 kW motor operating at 1425 rpm is chosen to power the conveyor. Three A-section V-belts running over pulleys with diameters of 125mm and 250mm are selected to transmit power from the motor to the screw. Gears and chains are also included in the drive mechanism with specified transmission ratios. The shaft, keys, bearings and clutch are designed. Material selections are made for the pulleys, V-belts and other components. Dimensions and specifications are provided for each designed part.
This document appears to be a chapter from a mechanical engineering textbook about clutches, brakes, couplings, and flywheels. It includes section outlines, examples, diagrams, and explanations of topics such as clutch and brake types, force analysis, temperature and energy considerations, friction materials, flywheel sizing, and motor characteristics. The overall content focuses on analyzing and designing mechanical components used for transferring motion and controlling speed and torque.
The document discusses balancing of rotating and reciprocating masses. It describes static and dynamic balancing, where static balancing ensures the center of gravity remains stationary during rotation and dynamic balancing ensures the resultant moments are equal to zero. Types of balancing discussed include balancing a single rotating mass with one or two masses in the same or different planes, as well as balancing multiple masses in the same or different planes. Examples provided calculate the magnitude and position of balancing masses given masses, radii of rotation, and angular positions of unbalanced masses.
This document discusses determining the deflection of beams under load. It introduces the concepts of bending moment (M), modulus of elasticity (E), and moment of inertia (I) in determining curvature and deflection. The maximum deflection can be obtained by solving the second order differential equation that governs the elastic curve of the beam, using the boundary conditions of the beam's supports and applying any loads. Examples are provided to demonstrate how to set up and solve the differential equations to find the deflection at any point on beams with various load configurations.
This document provides a tutorial on using Flow Simulation 2012 software. It covers topics such as opening SolidWorks models, creating flow simulation projects, specifying boundary conditions and engineering goals, running calculations, and viewing results through cut plots, surface plots, and other visualization tools. Step-by-step instructions are provided for analyzing examples involving a ball valve, conjugate heat transfer, porous media flow, hydraulic loss determination, drag coefficient calculation, and heat exchanger efficiency.
The document contains solutions to multiple problems involving calculating stresses in beams subjected to bending moments. For problem 4.1, it is determined that the stress at point A is 61.14 MPa (compressive) and at point B is 91.7 MPa (tensile). For problem 4.2, the stresses at points A and B are calculated to be -5.31 GPa and 3.365 GPa, respectively. Problem 4.3 involves calculating the largest bending moment that can be applied to an aluminum beam before yielding, which is determined to be 5.283 KN.m.
The purpose of this project is to compare the Normal Stresses induced in the Knuckle-Joint due to application of Tensile Force of 12KN by manual calculations and using Ansys Workbench. Also, to find minimum and maximum stress and Deformation in the Joint. In this report, Stresses found analytically are compared with the stresses found by the Analysis Software.
This document provides a geotechnical analysis and recommendations for a five-story school building. It includes:
- A description of the site conditions and soil profile based on borehole testing.
- Calculations of footing sizes, stress distributions, and settlements for shallow foundations to support the building loads.
- A recommendation to construct the building 10.5 meters from the top of a slope to achieve a safety factor of 1.5 against slope failure.
This document provides information about flexural testing of materials including steel, pine, and Douglas fir. It includes the experimental setup, procedures, formulas used to calculate flexural properties, graphs of load vs deformation, and tables of test data for each material. The key results are the ultimate flexural strengths of 2.2 kips for steel, 1.05 kips for pine, and still to be determined for Douglas fir. Comparisons are made between the flexural properties of the different materials.
Shaft design Erdi Karaçal Mechanical Engineer University of GaziantepErdi Karaçal
This document discusses the design of an industrial railway car shaft that is subjected to various loading conditions including bending, torsion, axial loading, and shear. The author performs both static failure analysis and fatigue failure analysis to size the shaft diameter. For fatigue analysis, the author calculates stress concentration factors and endurance limits. An initial diameter of 37.63mm is obtained from static analysis, which is then checked against fatigue analysis criteria. The final recommended diameter is 58mm, providing a safety factor of 1.55 when accounting for torsional loads in addition to bending. Deflection analysis is also performed to evaluate the shaft deformation.
ME 5720 Fall 2015 - Wind Turbine Project_FINALOmar Latifi
This document summarizes a project analyzing the design of a composite laminate for the spar of a wind turbine blade. A MATLAB code was developed to calculate stresses and determine if a proposed 7-ply hybrid glass fiber/carbon fiber laminate [0/45/0/45/0/45/0] would fail when subjected to expected wind loads. The code calculated lamina properties, stiffness matrices, strains and stresses for each ply. The Tsai-Hill failure criteria was applied and indicated the laminate would not fail. Therefore, the hybrid laminate was determined to be a viable solution for withstanding the loads on the spar.
This report summarizes the design of truss members and mounting brackets for a scaffolding system. Through iterative computer modeling and analysis in ANSYS, truss members with dimensions of 1.5 inches wide and 0.03125 inches thick were selected, providing a safety factor of 2.29 and a weight of 77.65 lbs. For the bracket design, various diameters and thicknesses were analyzed until a safe and lightweight design was achieved. The report demonstrates the application of engineering principles to size structural components for strength and minimize weight.
The beam section was designed with 42 prestressing strands located 130mm from the soffit. Section properties were calculated. Stress checks were performed at three stages to ensure stresses did not exceed allowable limits. A Magnel diagram showed the section satisfied design criteria with prestressing. Stirrup spacing of 150mm was chosen to resist shear. Total prestress losses were estimated at 26.67%. Deflections were calculated at various stages. A concrete slab was designed with reinforcement to span between beams.
Final Year Project Report on Structural Analysis and Design of Multistorey RCC Building for Earthquake Resistant Design as per IS Codes. - Khwopa College of Engineering - IOE, Tribhuvan university - Civil Engineering Final Report - Bachelor Level Project
This document provides design calculations for structural elements of a concrete car park structure according to BS-8110, including:
1. A one-way spanning roof slab with a span of 2.8m, designed as simply supported with 10mm main reinforcement bars at 300mm spacing and 8mm secondary bars.
2. A load distribution beam D and non-load bearing beam E, with calculations provided for beam D's dead and imposed loads.
3. Requirements include individual work submission by January 2nd, 2016 and assumptions to be clearly stated.
Established a relationship between weld splice length and diameter of the rei...NUR
Reinforcement strength, ductility and bendability properties are important components in the design of reinforced concrete members, as the strength of any member comes mainly from reinforcement. Strain compatibility and plastic behaviours’ are mainly depending on reinforcement ductility. In construction practice, often welding of the bars is required. Welding of reinforcement is an instant solution in many cases, whereas welding is not a routine connection process. Welding will cause deficiencies in reinforcement bars, metallurgical changes and recrystallization of the microstructure of particles. Weld metal toughness is extremely sensitive to the welding heat input that decreases both its strength and ductility.
This document contains a summary of a refresher course covering various structural analysis problems. It includes 5 situations involving calculating reactions, tensions, stresses, and shear forces for different structures. The document tests understanding through multiple choice questions after explaining the concepts and showing the calculations for each situation. The situations involve analyzing forces on a portable seat, cables supporting a ceiling, stresses on an element using Mohr's circle, forces on a bridge girder under loading, and stresses in a hollow circular signage pole.
The document analyzes and designs reinforced concrete beams using the strength design method. It provides examples of designing a simply supported rectangular beam, a cantilever beam, and an overhanging beam. The solutions include calculating loads, moments, required reinforcement, checking deflection requirements, and verifying the strength of the designed sections.
This report presents the structural analysis of knuckle joint using finite element analysis. The analysis considered the fracture failure of the structure from a loading of 70 kN axial load. It was found that the structure has a factor of safety of 2 for this loading and failure mode. The structure is therefore satisfactory for the desire design condition. The model is done with solid work and imported into Ansys. The FEM analysis had done with different mesh type and compared the result obtained. Further study in this direction can made by using various diameter of the pin, choosing the different material and the capacity to withstand load.
Comparative Study of Ferrocement Panels Under Blast Loading by Finite Element...IRJET Journal
This document analyzes the behavior of ferrocement panels under blast loading using finite element analysis in ANSYS. Ferrocement panels with 2-layer and 3-layer mesh configurations and thicknesses of 18mm and 25mm were modeled and subjected to blast loads at varying standoff distances. The results found that panels with greater thickness and mesh layers experienced less deformation and stress under blast loads. Specifically, the 25mm thick 3-layer panel showed 46% less deformation and 58% less strain compared to the 18mm thick 2-layer panel. Therefore, thicker ferrocement panels with more mesh layers provide better blast resistance and should be used for structures at high risk of explosions.
The document describes a tensile test experiment conducted to determine the mechanical properties of mild steel. The experiment involved applying a tensile load to a mild steel specimen and measuring its elongation. Key results were:
1) The specimen necked at a load of just over 8kN, exceeding its elastic limit.
2) The maximum load of 12kN caused necking in the specimen.
3) The specimen fractured at a load of 8.9kN after continued elongation beyond the maximum load.
4) Results from the experiment matched the expected mechanical behavior of mild steel under tension, validating the initial hypothesis.
This document presents the casing design and drilling engineering project for an oil and gas well. It includes:
1) Casing design calculations for 5 casing strings considering loading conditions like tension, compression, burst/collapse. Grade and dimensions are selected.
2) Drill string design calculations to determine minimum drill collar lengths at different depths to avoid compression on drill pipe.
3) Equations for axial loading, hydraulic calculations, and hoisting system are presented. Stress analysis shows second intermediate casing material needs upgrading to withstand loads.
4) Tables and figures show results like casing design, burst pressures, stress combinations, drill string specifications and calculated collar lengths.
1) The document discusses residual stresses in welded plate girders through several studies that used welding simulation and experimental testing. Residual stresses were calculated, measured through sectioning, and compared to Eurocode methods.
2) One study presented experimental and simulation results on the fabrication of welded plate girders under workshop conditions to predict imperfections. Special focus was placed on the effects of residual welding stresses.
3) Another study incorporated welding simulation results directly into structural analysis models of large components to analyze their capacity while accounting for residual stresses. A simple example analyzed weak-axis buckling.
This document contains instructions and questions for a Mechanics of Materials exam. It includes 12 questions related to topics like elastic constants, stresses and strains, beam loading diagrams, deflection, columns, strain energy, creep, fatigue, and stress concentration. Students are instructed to choose one question from each pair (1 OR 2, 3 OR 4, etc.) and show calculations when necessary. Data like material properties and dimensions are provided for selected questions.
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storie temporali, spettri di risposta
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Software Engineering and Project Management - Introduction, Modeling Concepts...Prakhyath Rai
Introduction, Modeling Concepts and Class Modeling: What is Object orientation? What is OO development? OO Themes; Evidence for usefulness of OO development; OO modeling history. Modeling
as Design technique: Modeling, abstraction, The Three models. Class Modeling: Object and Class Concept, Link and associations concepts, Generalization and Inheritance, A sample class model, Navigation of class models, and UML diagrams
Building the Analysis Models: Requirement Analysis, Analysis Model Approaches, Data modeling Concepts, Object Oriented Analysis, Scenario-Based Modeling, Flow-Oriented Modeling, class Based Modeling, Creating a Behavioral Model.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Discover the latest insights on Data Driven Maintenance with our comprehensive webinar presentation. Learn about traditional maintenance challenges, the right approach to utilizing data, and the benefits of adopting a Data Driven Maintenance strategy. Explore real-world examples, industry best practices, and innovative solutions like FMECA and the D3M model. This presentation, led by expert Jules Oudmans, is essential for asset owners looking to optimize their maintenance processes and leverage digital technologies for improved efficiency and performance. Download now to stay ahead in the evolving maintenance landscape.
Applications of artificial Intelligence in Mechanical Engineering.pdfAtif Razi
Historically, mechanical engineering has relied heavily on human expertise and empirical methods to solve complex problems. With the introduction of computer-aided design (CAD) and finite element analysis (FEA), the field took its first steps towards digitization. These tools allowed engineers to simulate and analyze mechanical systems with greater accuracy and efficiency. However, the sheer volume of data generated by modern engineering systems and the increasing complexity of these systems have necessitated more advanced analytical tools, paving the way for AI.
AI offers the capability to process vast amounts of data, identify patterns, and make predictions with a level of speed and accuracy unattainable by traditional methods. This has profound implications for mechanical engineering, enabling more efficient design processes, predictive maintenance strategies, and optimized manufacturing operations. AI-driven tools can learn from historical data, adapt to new information, and continuously improve their performance, making them invaluable in tackling the multifaceted challenges of modern mechanical engineering.
Rainfall intensity duration frequency curve statistical analysis and modeling...bijceesjournal
Using data from 41 years in Patna’ India’ the study’s goal is to analyze the trends of how often it rains on a weekly, seasonal, and annual basis (1981−2020). First, utilizing the intensity-duration-frequency (IDF) curve and the relationship by statistically analyzing rainfall’ the historical rainfall data set for Patna’ India’ during a 41 year period (1981−2020), was evaluated for its quality. Changes in the hydrologic cycle as a result of increased greenhouse gas emissions are expected to induce variations in the intensity, length, and frequency of precipitation events. One strategy to lessen vulnerability is to quantify probable changes and adapt to them. Techniques such as log-normal, normal, and Gumbel are used (EV-I). Distributions were created with durations of 1, 2, 3, 6, and 24 h and return times of 2, 5, 10, 25, and 100 years. There were also mathematical correlations discovered between rainfall and recurrence interval.
Findings: Based on findings, the Gumbel approach produced the highest intensity values, whereas the other approaches produced values that were close to each other. The data indicates that 461.9 mm of rain fell during the monsoon season’s 301st week. However, it was found that the 29th week had the greatest average rainfall, 92.6 mm. With 952.6 mm on average, the monsoon season saw the highest rainfall. Calculations revealed that the yearly rainfall averaged 1171.1 mm. Using Weibull’s method, the study was subsequently expanded to examine rainfall distribution at different recurrence intervals of 2, 5, 10, and 25 years. Rainfall and recurrence interval mathematical correlations were also developed. Further regression analysis revealed that short wave irrigation, wind direction, wind speed, pressure, relative humidity, and temperature all had a substantial influence on rainfall.
Originality and value: The results of the rainfall IDF curves can provide useful information to policymakers in making appropriate decisions in managing and minimizing floods in the study area.
Design and optimization of ion propulsion dronebjmsejournal
Electric propulsion technology is widely used in many kinds of vehicles in recent years, and aircrafts are no exception. Technically, UAVs are electrically propelled but tend to produce a significant amount of noise and vibrations. Ion propulsion technology for drones is a potential solution to this problem. Ion propulsion technology is proven to be feasible in the earth’s atmosphere. The study presented in this article shows the design of EHD thrusters and power supply for ion propulsion drones along with performance optimization of high-voltage power supply for endurance in earth’s atmosphere.
Modellazione di una copertura reticolare in acciaio
1. 1
Pag. 1
Università degli studi G. d’Annunzio di Chieti-Pescara
Dipartimento di Ingegneria & Geologia
Corso di laurea magistrale in Ingegneria delle Costruzioni LM-24
COSTRUZIONI METALLICHE
Prof. Brando Giuseppe - A.A. 2020-2021
Modellazione e analisi di una copertura reticolare in acciaio
D’ANGELO Michele Matricola 3210376
2. 2
Pag. 2
Sommario
1. DESCRIZIONE DEL PROGETTO.............................................................................................................................4
1.1 NORMATIVA DI RIFERIMENTO .....................................................................................................................4
1.2 MATERIALE UTILIZZATO ...............................................................................................................................5
2. PREDIMENSIONAMENTO STRUTTURA................................................................................................................6
2.1 CALCOLO SEZIONI PROFILATI .......................................................................................................................7
2.1.1 1° PRE-DIMENSIONAMENTO.....................................................................................................................7
3. PRE-PROCESSIONE............................................................................................................................................11
3.1 CREAZIONE MAGLIA DEI NODI ...................................................................................................................11
3.2 SCELTA DEL MATERIALE .............................................................................................................................12
3.3 SCELTA DEI PROFILATI IN ACCIAIO .............................................................................................................12
3.4 SCELTA DEI VINCOLI ...................................................................................................................................13
3.7 INSERIMENTO DEI CARICHI NELLA STRUTTURA .........................................................................................14
4. POST-PROCESSIONE..........................................................................................................................................16
4.1 CONTROLLI SUL MODELLO .........................................................................................................................16
4.1.1 CONTROLLO DELLE REAZIONI VINCOLARI ...............................................................................................16
4.1.2 CONTROLLO DELLE SOLLECITAZIONI .......................................................................................................17
4.2 ALCUNI RISULTATI DELLA POST-PROCESSIONE ..........................................................................................18
4.3 ANALISI DI BUCKLING .................................................................................................................................20
5 VERIFICHE CON EUROCODICE3:05.....................................................................................................................22
5.1 1°ITERAZIONE.............................................................................................................................................22
5.2 2°ITERAZIONE.............................................................................................................................................24
5.3 3°ITERAZIONE.............................................................................................................................................25
6 ANALISI DI PUSHOVER .......................................................................................................................................27
6.1 PUSH-DOWN ..............................................................................................................................................27
6.1 PUSH-UP.....................................................................................................................................................30
7. RIEPILOGO ELEMENTI .......................................................................................................................................32
8. VERIFICA DEL COLLEGAMENTO – ASTA 508X40 ...............................................................................................33
8.1 VERIFICA A TAGLIO DEI BULLONI DEL CORRENTE ......................................................................................33
8.2 VERIFICA A RIFOLLAMENTO DEI FAZZOLETTI D’ESTREMITA’ DEL CORRENTE ............................................34
8.3 VERIFICA A SALDATURA FAZZOLETTI..........................................................................................................35
8.4 VERIFICA A “BLOCK TEARING” DEI PIATTI VERTICALI .................................................................................37
9. VERIFICA DEL COLLEGAMENTO – ASTA 508X20 ...............................................................................................38
8.1 VERIFICA A TAGLIO DEI BULLONI DEL CORRENTE ......................................................................................39
8.2 VERIFICA A RIFOLLAMENTO DEI FAZZOLETTI D’ESTREMITA’ DEL CORRENTE ............................................40
8.4 VERIFICA A “BLOCK TEARING” DEI PIATTI ORIZZONTALI............................................................................42
4. 4
Pag. 4
1. DESCRIZIONE DEL PROGETTO
Nel seguente progetto andremo a modellare una copertura reticolare in acciaio, al seguito di
questa modellazione eseguire delle verifiche eurocodice3.05, p-delta, buckling e infine
l’analisi di pushover. Innanzitutto, come primo passo bisogna pre-dimensionare la struttura
tramite delle semplificazioni che vedremo nel capitolo 2.
1.1 NORMATIVA DI RIFERIMENTO
Per la progettazione della copertura è stata utilizzato il capitolo 4 della normativa per le costruzioni
(NTC2018).
Figura 0 Normativa di riferimento
5. 5
Pag. 5
1.2 MATERIALE UTILIZZATO
Il materiale impiegato per gli elementi strutturali è l’acciaio S275 H per le aste, e l’acciaio S355 per i
collegamenti, con le seguenti caratteristiche:
Figura 1 Laminati a caldo con profili a sezione curva
6. 6
Pag. 6
2. PREDIMENSIONAMENTO STRUTTURA
I dati della struttura sono i seguenti:
H= 14250mm
L= 1425000mm
Gli appoggi sono posizionati a 1,5 moduli dal confine della copertura, la distanza tra le
cerniere è 133000 mm. Con il seguente schema semplificativo calcoleremo le sollecitazioni
della copertura. (Fig.1)
Figura 1 Planimetria e modello di calcolo
7. 7
Pag. 7
2.1 CALCOLO SEZIONI PROFILATI
2.1.1 1° PRE-DIMENSIONAMENTO
Nella tabella seguente sono elencati tutti i dati per il predimensionamento della copertura.
DATI DI INPUT
Altezza 14,25 m
Lunghezza senza sbalzi 114000 mm
Lunghezza Totale 142,5 m 142500 mm
Interasse 50 mm
Lunghezza 9500 mm 9,5 m
Lunghezza Copertura 95000 mm 95 m
Lunghezza/2 4,75 m
Lunghezza Copertura*3/10 28,5 m
Di seguito è rappresentata la tabella con i carichi rappresentativi della capriata, per il
seguente calcolo viene utilizzata la combinazione fondamentale: 1.3G1+1.5G2+1.5Q.
CARICHI
Peso proprio Struttura 0,1 kN/m2 0,0001 Mpa
#Primo valore imposto è 1 kN/m2 i valori successivi
sono derivanti da iterazioni.
Peso proprio Copertura 0,8 kN/m2 0,0008 Mpa
Carico Vento 0,56 kN/m2 0,00056 Mpa
Carico da Neve 1 kN/m2 0,001 Mpa
Combinazione Fondamentale allo SLU:
Combinazione fondamentale 2,83 kPa
Risultante del carico 26,885 kN/m
𝑞 = 𝑄 × 𝑙 = 2.83 𝑥 114 = 26.88 𝑘𝑁/𝑚
8. 8
Pag. 8
Formulario:
𝐌𝐌𝐚𝐱 =
𝐪 × 𝐥𝟐
𝟖
𝑪 =
𝑴
𝑯
𝐀𝐦𝐢𝐧;𝐒𝐮𝐩
=
𝐂
𝐟𝐲𝐃
× 𝛘
𝐀𝐦𝐢𝐧,𝐢𝐧𝐟 =
𝐓
𝐟𝐲𝐝
𝐀𝐦𝐢𝐧,𝐝𝐢𝐚𝐠 =
𝐂 × 𝐜𝐨𝐬 𝛂
𝛘 × 𝐟𝐲𝐝
T=H
Nella tabella seguente c’è il calcolo della sollecitazione del momento in mezzeria:
CALCOLO DELLE SOLLECITAZIONI
Momento max (Mezzeria) 43674682500 N*mm 43674,683 kN*m
Compressione 3064,89 kN
Trazione 3064,89
X 0,5
Amin,sup 0,027388379 m2 273,88379 cm2
Amin,inf 0,013694189 m2 136,94189 cm2
Amin,diag 0,00691661 m2 69,166101 cm2
La seguente tabella rappresenta il momento a 3/10 della copertura:
Momento max (3/10) 25476,898 kN*m
Compressione 1787,8525 kN
Trazione 1787,8525
X 0,5
Amin,sup 0,015976554 m2 159,76554 cm2
Amin,inf 0,007988277 m2 79,882771 cm2
Amin,diag 0,004034689 m2 40,346892 cm2
Al termine di questi calcoli, troveremo delle sezioni di primo pre-dimensionamento che
utilizzeremo per trovare un primo peso della struttura per continuare l’iterazione.
9. 9
Pag. 9
ABACO ELEMENTI
Sez. N elem. L(m) P(Kg/m) PESO TOTALE
grigliati 406.4x25 450 9,5 235 1004625 kg 10046,25 kN
406.4x12 450 9,5 117 500175 kg 5001,75 kN
diagonali 406,4x6 900 15,02082 59,2 800309,2 kg 8003,092 kN
totale 1800 34,02082 411,2 2305109 kg 23051,09 kN
Chilo-Newton al metroquadro dopo la prima iterazione:
PESO DELLA STRUTTURA 1,135172289 kPa
2.1.1 1°PRE-DIMENSIONAMENTO
Di seguito c’è il valore della risultante di carico calcolata tramite il nuovo peso.
Combinazione fondamentale 4,169 kPa
Risultante del carico 39,6055 kN/m
Nel secondo pre-dimensionamento andremo ad utilizzare il nuovo peso della copertura
trovato dalla prima analisi, così facendo dimensioneremo di nuovo le sezioni.
CALCOLO DELLE SOLLECITAZIONI
Momento max (Mezzeria) 64339134750 N*mm 64339,135 kN*m
Compressione 4515,027 kN
Trazione 4515,027
X 0,5
Amin,sup 0,04034705 m2 403,4705 cm2
Amin,inf 0,020173525 m2 201,73525 cm2
Amin,diag 0,010189169 m2 101,89169 cm2
La seguente tabella rappresenta il momento a 3/10 della copertura:
Momento max (3/10) 37531,162 kN*m
Compressione 2633,76575 kN
Trazione 2633,76575
X 0,5
Amin,sup 0,023535779 m2 235,35779 cm2
Amin,inf 0,01176789 m2 117,6789 cm2
Amin,diag 0,005943682 m2 59,436818 cm2
Tabella dei profilati metallici a sezione circolare utilizzati per la copertura:
10. 10
Pag. 10
Al termine di questi calcoli, troveremo delle sezioni di primo pre-dimensionamento che
utilizzeremo per trovare un primo peso della struttura per continuare l’iterazione.
ABACO ELEMENTI
Sez. N elem L(m) P(Kg/m) PESO TOTALE
grigliati 406.4x40 400 9,5 361 1371800 kg 13718 kN
406.4x20 420 9,5 191 762090 kg 7620,9 kN
406.4x10 80 9,5 97,8 74328 kg 743,28 kN
diagonali 406.4x10 900 15,02 97,8 1322060 kg 13220,6 kN
totale 1800 34,02 649,8 3455950 kg 34559,5 kN
Di seguito il nuovo peso della struttura:
PESO DELLA STRUTTURA 1,701914632 kPa
Sostituendo il nuovo peso della struttura, lo spessore delle sezioni viene verificato, quindi la
convergenza è stata raggiunta.
11. 11
Pag. 11
3. PRE-PROCESSIONE
In questo capitolo verrà mostrata la parte di modellazione a seguito del pre-dimensionamento,
questa parte della progettazione avverrà con un programma ad elementi finiti (Midas Gen).
3.1 CREAZIONE MAGLIA DEI NODI
In evidenza c’è la sezione nella quale si inseriscono le coordinate del primo nodo, in tal caso
è stato posizionato a (0,0,0).
Figura 2 Reticolo dei nodi
Nella figura 3 viene rappresentato il comando con il quale viene copiato il primo nodo per n
volte.
Figura 3 Copia dei nodi
12. 12
Pag. 12
3.2 SCELTA DEL MATERIALE
A questo punto viene scelto il materiale, dalla libreria di Midas è possibile scegliere il
materiale standard oppure definirlo tramite le varie proprietà meccaniche.
Figura 4 Materiale da costruzione
3.3 SCELTA DEI PROFILATI IN ACCIAIO
A seguito del pre-dimensionamento abbiamo trovato le sezioni minime per la struttura.
Vengono inserite con il comando in figura 5.
Figura 5 Sezioni dei profilati
13. 13
Pag. 13
3.4 SCELTA DEI VINCOLI
In questo passo inseriamo i vincoli, in tal caso inseriamo una cerniera in un pilastro e nei
restanti 3 pilastri ci sono delle slitte che permettono alla struttura di “respirare”.
Figura 6 Planimetria dei vincoli
Figura 6 beam and release
14. 14
Pag. 14
3.5 ASSEGNAZIONE DELLA TIPOLOGIA DI CARICHI
La “static load case” viene utilizzata per immagazzinare tutte le tipologie di carichi con le
relative caratteristiche.
Figura 7 Classificazione dei carichi
3.7 INSERIMENTO DEI CARICHI NELLA STRUTTURA
In questa figura viene mostrato il comando utilizzato per inserire gli “static load case” sulla
struttura.
Figura 8 Carichi nodali
16. 16
Pag. 16
4. POST-PROCESSIONE
In questo capitolo andremo ad eseguire alcune verifiche base per avere una maggiore
affidabilità nel momento in cui faremo delle analisi più avanzate, ad esempio verificare che
negli appoggi ci sia come reazione vincolare il peso totale diviso “n” appoggi.
4.1 CONTROLLI SUL MODELLO
4.1.1 CONTROLLO DELLE REAZIONI VINCOLARI
Nella figura 4.1 c’è la verifica delle reazioni vincolari nei 4 appoggi derivanti dal peso
permanente G2 pari a 0.8 kN/m2.
Fy=(0.8x142.5x142.5)/4= 4061.25 kN
Figura 4.1 Reazioni vincolari dovuti a G2
Nella figura 4.2 c’è la verifica delle reazioni vincolari nei 4 appoggi derivanti dal peso
accidentale neve pari a 1 kN/m2.
Fy=(1x142.5x142.5)/4= 5076 kN
Figura 4.2 Reazioni vincolari dovuti a S
Nella figura 4.3 c’è la verifica delle reazioni vincolari nei 4 appoggi derivanti dalla
temperatura
17. 17
Pag. 17
Figura 4.3 Reazioni vincolari dovuti a DeltaT
4.1.2 CONTROLLO DELLE SOLLECITAZIONI
In seguito alla modellazione dei “beam and release” una verifica da apporre al modello
affinché esso sia corretto è controllare che i momenti nel piano dei tubolari sia trascurabile.
Infatti come si può ben notare i momenti sono dell’ordine di un paio di decine tale cosa può
farci valutare la modellazione di questo vincolo corretta.
Figura 4.3 Sollecitazione Mz
18. 18
Pag. 18
4.2 ALCUNI RISULTATI DELLA POST-PROCESSIONE
Il controllo della deformazione massima in mezzeria va verificato con la normativa tecnica
del 2018 (NTC18).
Figura 4.4 Deformazione DxDyDz in combinazione fondamentale
La freccia massima nel modello è 250 mm mentre per la normativa è 520 mm in quanto max
è 1/200 di 104 metri.
Tabella 1 Stralcio di normativa
19. 19
Pag. 19
Lo schema di calcolo assunto porta a queste deformazioni in quanto solo uno degli appoggi è
un incastro quindi non trasla ma resta fermo mentre gli altri appoggi si muovono permettendo
alla struttura di “respirare”.
Figura 2.5 Deformazioni negli appoggi dovute alla variazione di temperatura
20. 20
Pag. 20
4.3 ANALISI DI BUCKLING
Nell’analisi di buckling è stato inserito il carico con la combinazione fondamentale. Tale
verifica serve a calcolare un fattore che quanto siamo distanti dalla condizione di instabilità.
Figura 2.6.1 Inserimento dell’analisi di buckling
Già dai primi modi abbiamo un fattore di scala maggiore di 3, cioè il carico massimo che
possiamo avere sulla struttura è 3.5 volte minore di quello che applicato alla struttura
provocherebbe l’instabilità
Figura 2.6.2 Inserimento dell’analisi di buckling
21. 21
Pag. 21
Nella modellazione si può utilizzare uno dei modi più lineare per utilizzarlo come
imperfezione del modello.
Figura 2.6.3 Modo di vibrare numero 18
22. 22
Pag. 22
5 VERIFICHE CON EUROCODICE3:05
5.1 1°ITERAZIONE
Facendo la verifica con le sezioni del predimensionamento abbiamo notato che alcuni
coefficienti tendono a infinito a causa della rottura per sforzo normale.
Figura 5.1 Steel Design
Facendo uno zoom sugli appoggi si nota un rapporto che tende a infinito.
Figura 5.2 Steel design appoggi
Nell’immagine seguente è rappresentato un grafico con il rapporto dei momenti d’esercizio e
i momenti resistenti di tutti gli elementi.
24. 24
Pag. 24
5.2 2°ITERAZIONE
Nella seconda iterazione possiamo notare che i coefficienti si sono abbassati ma comunque
restano troppo vicini all’unità. Quindi è raccomandabile che la sezione numero 1 abbia uno
spessore maggiore.
Figura 5.4 Steel design della seconda iterazione
Nell’immagine seguente è rappresentato un grafico con il rapporto dei momenti d’esercizio e
i momenti resistenti di tutti gli elementi.
Figura 5.5 Ratio coefficienti degli elementi
25. 25
Pag. 25
5.3 3°ITERAZIONE
Nella terza iterazione notiamo che le sezioni lavorano da un minimo di 45% a un massimo
del 88%. Possiamo considerare questo dimensionamento per la progettazione.
Figura 5.6 Steel design della terza iterazione
Nell’immagine seguente è rappresentato un grafico con il rapporto dello sforzo normale
d’esercizio e lo sforzo normale resistente di tutti gli elementi.
Figura 5.7 Ratio coefficienti degli elementi
27. 27
Pag. 27
6 ANALISI DI PUSHOVER
6.1 PUSH-DOWN
Nelle immagini seguenti viene descritto il modo di eseguire l’analisi di pushover con il
software Midas. Il carico iniziale utilizzato per l’analisi è quella fondamentale
1,3G1+1,5G2+1,5S successivamente verrà incrementato il carico da neve per portare la
struttura alla creazione delle cerniere plastiche.
Figura 6 Impostazione analisi di pushover
28. 28
Pag. 28
Figura 6.1 Legame costitutivo
Nelle immagini seguenti viene descritto il modo di eseguire l’analisi di pushover con il
software Midas. Il carico iniziale utilizzato per l’analisi è quella fondamentale
1,3G1+1,5G2+1,5S successivamente verrà incrementato il carico da neve per portare la
struttura alla creazione delle cerniere plastiche.
Figura 6.1 Risultati in termini di deformazione-sforzo
29. 29
Pag. 29
Figura 6.2 Cerniere plastiche
Figura 6.3 Formazione delle prime cerniere plastiche
Figura 6.4 Ulteriore formazione di cerniere plastiche
30. 30
Pag. 30
6.1 PUSH-UP
Nelle immagini seguenti viene mostrata l’analisi di push-up. Il carico iniziale utilizzato per
l’analisi è quella fondamentale 1,3G1+1,5G2+1,5S successivamente verrà incrementato il
carico da vento per portare la struttura alla creazione delle cerniere plastiche.
Figura 6.5 Risultati in termini di deformazione-sforzo
Figura 6.6 Formazione delle prime cerniere plastiche
31. 31
Pag. 31
Figura 6.7 Fase prima della rottura delle cerniere plastiche
Figura 6.8 Rottura cerniere plastiche
32. 32
Pag. 32
7. RIEPILOGO ELEMENTI
A termine di queste ultime verifiche sulle cerniere plastiche abbiamo eseguito l’abaco degli
elementi di progetto:
ABACO ELEMENTI
sez N elem L(m) P(Kg/m) PESO
TOTALE
508x40 450 9.5 462 1975050 kg 19750.5 kN
508x40 16 15.02 462 111027.8
508x20 480 15.02 241 1737514 kg 17375.14 kN
508x20 254 9.5 241 581533
508x16 472 9.5 194 869896 kg 8698.96 kN
508x16 128 15.02 194 372976.6
508x50 16 15.02 565 135780.8 kg 1357.808 kN
totale 1418 39.54 2359 5783778 kg 47182.4 kN
Abaco degli elementi
Di seguito c’è la tabella dei profilati cavi, in quest’ultima abbiamo individuato i pesi e i
diametri per la progettazione.
Tabella dei profilati
33. 33
Pag. 33
8. VERIFICA DEL COLLEGAMENTO – ASTA 508X40
Le forze con le quali viene verificato il collegamento, sono le forze massime che possono
svilupparsi in ciascuna asta in modo tale che la resistenza del nodo sia superiore alla
resistenza delle singole aste. Per tale motivo, le forze da considerare sono:
Elementi
Sezioni Area[m2]
508x50 0.0719
508x40 0.0588
508x16 0.0247
508x20 0.0307
Resistenza[Mpa] 275
Sezioni
Ned(50) 18830.95 KN
Ned(40) 15400 KN
Ned(20) 6469.05 KN
Ned(16) 8040.48 KN
Piastra S355
Fu [Mpa] 510
Ym1 1,05
Ym2 1,25
t[mm] 60
8.1 VERIFICA A TAGLIO DEI BULLONI DEL CORRENTE
[8.1]
Fvrd 326.8 KN
Poiché la Fvrd>Ved, la verifica risulta soddisfatta.
[8.2]
Verifica a taglio dei bulloni del corrente
34. 34
Pag. 34
8.2 VERIFICA A RIFOLLAMENTO DEI FAZZOLETTI D’ESTREMITA’ DEL
CORRENTE
Bulloni area[mm2] d[mm] Fvb[Mpa] Alfa n a1[mm] a2 p1 p2
M36 817 36 1000 0.5 24 110 50 100 80
Distanze dei bulloni
[8.3]
Verifica a rifollamento dei fazzoletti d'estremità del corrente
Fbrd[kN] 1303.877333 Verificato il rifollamento
Fbrd[kN] 1243.584 Verificato il rifollamento
alfa bullone esterno 0.675925926
alfa bullone interno 1
k bullone esterno 2.188888889
k bullone interno 1.411111111
Ved[kN] 320.07 Verificato a taglio
35. 35
Pag. 35
Poiché la Fbrd>Ved, la verifica risulta soddisfatta.
[8.4]
8.3 VERIFICA A SALDATURA FAZZOLETTI
L’equazione 8.1 esprime la forza che agisce su ciascun fazzoletto:
[8.5]
Ipotizziamo un cordone d’angolo di altezza pari a 8 mm e una lunghezza pari a
720 mm, la tensione tangenziale è la seguente:
[8.6]
Tale saldatura viene verifica se:
[8.7]
Profilato 508x40
Verifica a taglio dei bulloni del corrente
Ved[kN] 320.07 Verificato a taglio
37. 37
Pag. 37
8.4 VERIFICA A “BLOCK TEARING” DEI PIATTI VERTICALI
Prospetto collegamento 508x40
[8.8]
[8.9]
[8.10]
Verifica a "Block Tearing" del piatto verticale
A netta 18480
distanza tra bulloni 44
n distanze 7
A nv (2 Lati) 30480
distanza tra bulloni 54
distanza dal bordo 92
n distanze 3
Vb,Rd 15669274.01 N
15669.27401 KN
verifica a block tearing
Tabella di calcolo
38. 38
Pag. 38
9. VERIFICA DEL COLLEGAMENTO – ASTA 508X20
Le forze con le quali viene verificato il collegamento, sono le forze massime che possono
svilupparsi in ciascuna asta in modo tale che la resistenza del nodo sia superiore alla
resistenza delle singole aste. Per tale motivo, le forze da considerare sono:
Elementi
Sezioni Area[m2]
508x50 0.0719
508x40 0.0588
508x16 0.0247
508x20 0.0307
Resistenza[Mpa] 275
Tabella di calcolo
Sezioni
Ned(50) 18830.95 KN
Ned(40) 15400 KN
Ned(20) 6469.05 KN
Ned(16) 8040.48 KN
Tabella di calcolo
Piastra S355
Resistenza[Mpa] 510
Ym1 1,05
Ym2 1,25
t[mm] 60
Larghezza[mm] 948
Lunghezza[mm] 428
Tabella di calcolo
Tabella di calcolo
Bulloni M36
area[mm2] 817
d[mm] 36
Fvb[Mpa] 1000
Alfa 0,5
39. 39
Pag. 39
8.1 VERIFICA A TAGLIO DEI BULLONI DEL CORRENTE
[9.1]
Fvrd 326.8 KN
[9.2]
Verifica a taglio dei bulloni del corrente
Ved[kN] 134,77 Verificato il rifollamento
40. 40
Pag. 40
8.2 VERIFICA A RIFOLLAMENTO DEI FAZZOLETTI D’ESTREMITA’ DEL
CORRENTE
Distanze dei bulloni
Distanze dei bulloni
Poiché la Fbrd>Ved, la verifica risulta soddisfatta.
[9.2]
Verifica a taglio dei bulloni del corrente
Ved[kN] 134,77 Verificato il rifollamento
n a1[mm] a2 p1 p2
24 80 50 80 80
Verifica a rifollamento dei fazzoletti d'estremità del corrente
Ved[kN] (Esterno) 946,6506667 Verificato il rifollamento
Ved[kN] (Interno) 921,1733333 Verificato il rifollamento
alfa bullone esterno 0,490740741
alfa bullone interno 0,740740741
k bullone esterno 2,188888889
k bullone interno 1,411111111
41. 41
Pag. 41
9.3 VERIFICA A SALDATURA FAZZOLETTI
L’equazione 8.1 esprime la forza che agisce su ciascun fazzoletto:
[8.5]
Ipotizziamo un cordone d’angolo di altezza pari a 8 mm e una lunghezza pari a
720 mm, la tensione tangenziale è la seguente:
[8.6]
Tale saldatura viene verifica se:
[8.7]
Verifica Saldatura Fazzoletti
F[kN] 3234,52381
t// 115518,7075
beta w 0,62
S 420
verifica la saldatura
42. 42
Pag. 42
8.4 VERIFICA A “BLOCK TEARING” DEI PIATTI ORIZZONTALI
Prospetto collegamento 508x20
[8.8]
[8.9]
[8.10]
Verifica a "Block Tearing" del piatto orizzontale
A netta 17640 mmq
Distanza tra bulloni 42 mm
Numero di spazi 7 adim
Anv (2 Lati) 19680 mmq
distanza dal bordo 42 mm
distanza tra bulloni 80 mm
Numero di spazi 2 adim
Vb,rd 6825439,937 N
6825,439937 kN
Verifica a block tearing