This document outlines a seminar on modeling, designing, and optimizing a multi-story steel structure using ETABS. It describes a 10-story steel braced building model with elevator cores and shear walls. The model is subjected to vertical, seismic, and wind loads. The document discusses importing the architectural grid and 3D model from DXF files, creating beams, columns, and braces using the GUI tools, and applying static and dynamic loads. It also covers steel frame design, concrete foundation detailing, and creating output reports.
Etabs example-rc building seismic load response-Bhaskar Alapati
This document provides step-by-step instructions for performing a modal response spectra analysis and design of a 10-story reinforced concrete building model in ETABS. It describes opening an existing model, defining response spectrum functions and cases based on IBC2000 parameters, running a modal analysis and response spectral analysis, and reviewing results including mode shapes, member forces, and designing concrete frames and shear walls. The objective is to demonstrate modal response spectra analysis and design of the building model according to IBC2000 seismic code provisions.
This document discusses the design of reinforced concrete deep beams. It defines deep beams as having a span/depth ratio less than 2 or a continuous beam ratio less than 2.5. Deep beams behave differently than elementary beam theory due to non-linear stress distributions. Their behavior depends on loading type and cracking typically occurs between one-third to one-half of the ultimate load. Design considerations include checking for minimum thickness, flexural design, shear design, and anchorage of tension reinforcement.
Comparision of Design Codes ACI 318-11, IS 456 2000 and Eurocode IIijtsrd
This document compares the design code specifications of ACI 318-11, IS 456:2000, and Eurocode II. It discusses some key differences between the codes, such as their stress-strain block parameters, L/D ratios, load combinations, elastic modulus of concrete, and design strength limits of concrete. The document aims to compare the broader design criteria and calculate the steel area required for structural members based on each code, in order to perform a comparative analysis. Some notable differences highlighted include Eurocode II having more stringent L/D ratios and load combinations compared to the other codes.
Base shear is the maximum expected lateral force at the base of a structure due to seismic activity. It depends on soil conditions, proximity to faults, structure properties, and total weight. ETABS compares the dynamic base shear from response spectrum analysis to 85% of the static base shear. If dynamic is less than 85% of static, the scale factor is adjusted so that dynamic equals 85% of static and analysis is rerun. The document provides steps to match base shear in ETABS by modifying the scale factor if needed.
The document provides details on the design of a reinforced concrete column footing to support a column load of 1100kN from a 400mm square column. It describes the design process which includes determining the footing size, calculating bending moment, reinforcement requirements, checking shear capacity and development length. The design example shows a 3.5m x 3.5m square footing with 12mm diameter bars at 100mm c/c is adequate to support the given load based on the specified material properties and design codes. Reinforcement and footing details are also provided.
This document discusses the design of compression members subjected to axial load and biaxial bending. It introduces the concept of biaxial eccentricities and explains that columns should be designed considering possible eccentricities in two axes. The document outlines the method suggested by IS 456-2000, which is based on Breslar's load contour approach. It relates the parameter αn to the ratio of Pu/Puz. Finally, it provides a step-by-step process for designing the column section, which involves determining uniaxial moment capacities, computing permissible moment values from charts, and revising the section if needed. It also briefly mentions the simplified method according to BS8110.
This document outlines a seminar on modeling, designing, and optimizing a multi-story steel structure using ETABS. It describes a 10-story steel braced building model with elevator cores and shear walls. The model is subjected to vertical, seismic, and wind loads. The document discusses importing the architectural grid and 3D model from DXF files, creating beams, columns, and braces using the GUI tools, and applying static and dynamic loads. It also covers steel frame design, concrete foundation detailing, and creating output reports.
Etabs example-rc building seismic load response-Bhaskar Alapati
This document provides step-by-step instructions for performing a modal response spectra analysis and design of a 10-story reinforced concrete building model in ETABS. It describes opening an existing model, defining response spectrum functions and cases based on IBC2000 parameters, running a modal analysis and response spectral analysis, and reviewing results including mode shapes, member forces, and designing concrete frames and shear walls. The objective is to demonstrate modal response spectra analysis and design of the building model according to IBC2000 seismic code provisions.
This document discusses the design of reinforced concrete deep beams. It defines deep beams as having a span/depth ratio less than 2 or a continuous beam ratio less than 2.5. Deep beams behave differently than elementary beam theory due to non-linear stress distributions. Their behavior depends on loading type and cracking typically occurs between one-third to one-half of the ultimate load. Design considerations include checking for minimum thickness, flexural design, shear design, and anchorage of tension reinforcement.
Comparision of Design Codes ACI 318-11, IS 456 2000 and Eurocode IIijtsrd
This document compares the design code specifications of ACI 318-11, IS 456:2000, and Eurocode II. It discusses some key differences between the codes, such as their stress-strain block parameters, L/D ratios, load combinations, elastic modulus of concrete, and design strength limits of concrete. The document aims to compare the broader design criteria and calculate the steel area required for structural members based on each code, in order to perform a comparative analysis. Some notable differences highlighted include Eurocode II having more stringent L/D ratios and load combinations compared to the other codes.
Base shear is the maximum expected lateral force at the base of a structure due to seismic activity. It depends on soil conditions, proximity to faults, structure properties, and total weight. ETABS compares the dynamic base shear from response spectrum analysis to 85% of the static base shear. If dynamic is less than 85% of static, the scale factor is adjusted so that dynamic equals 85% of static and analysis is rerun. The document provides steps to match base shear in ETABS by modifying the scale factor if needed.
The document provides details on the design of a reinforced concrete column footing to support a column load of 1100kN from a 400mm square column. It describes the design process which includes determining the footing size, calculating bending moment, reinforcement requirements, checking shear capacity and development length. The design example shows a 3.5m x 3.5m square footing with 12mm diameter bars at 100mm c/c is adequate to support the given load based on the specified material properties and design codes. Reinforcement and footing details are also provided.
This document discusses the design of compression members subjected to axial load and biaxial bending. It introduces the concept of biaxial eccentricities and explains that columns should be designed considering possible eccentricities in two axes. The document outlines the method suggested by IS 456-2000, which is based on Breslar's load contour approach. It relates the parameter αn to the ratio of Pu/Puz. Finally, it provides a step-by-step process for designing the column section, which involves determining uniaxial moment capacities, computing permissible moment values from charts, and revising the section if needed. It also briefly mentions the simplified method according to BS8110.
ANALYSIS AND DESIGN OF HIGH RISE BUILDING BY USING ETABSila vamsi krishna
RESULT OF ANALYSIS:
https://www.slideshare.net/ilavamsikrishna/results-of-etabs-on-high-rise-residential-buildings
ANALYSIS AND DESIGN OF BUILDING BY USING STAAD PRO PPT link :
https://www.slideshare.net/ilavamsikrishna/analysis-and-design-of-mutistoried-residential-building-by-using-staad-pro
FOR FULL REPORT:
vamsiila@gmail.com
The lecture is in support of:
(1) The Design of Building Structures (Vol.1, Vol. 2), rev. ed., PDF eBook by Wolfgang Schueller, 2016
(2) Building Support Structures, Analysis and Design with SAP2000 Software, 2nd ed., eBook by Wolfgang Schueller,
The SAP2000V15 Examples and Problems SDB files are available on the Computers & Structures, Inc. (CSI) website: http://www.csiamerica.com/go/schueller
This document provides an overview of the design of steel beams. It discusses various beam types and sections, loads on beams, design considerations for restrained and unrestrained beams. For restrained beams, it covers lateral restraint requirements, section classification, shear capacity, moment capacity under low and high shear, web bearing, buckling, and deflection checks. For unrestrained beams, it discusses lateral torsional buckling, moment and buckling resistance checks. Design procedures and equations for determining effective properties and capacities are also presented.
The document summarizes the major changes between the 1997 and 1994 versions of the Uniform Building Code (UBC) related to earthquake resistant design. Key changes included expanding the soil profile types from 4 to 6 types dependent on seismic zone, introducing two new structural framing systems, basing seismic design on strength-level rather than service-level, and making the design base shear a function of both horizontal and vertical ground motion components. The 1997 UBC also included simplified methods for determining design base shear in shorter buildings, calculating displacements and drift, and distributing seismic forces.
This document discusses the design of biaxially loaded columns. It defines a biaxially loaded column as one where axial load acts with eccentricities about both principal axes, causing bending in two directions. Several methods for analyzing and designing biaxially loaded columns are presented, including the load contour method, reciprocal load method, strain compatibility method, and equivalent eccentricity method. An example problem demonstrates using the reciprocal load method to check the adequacy of a trial reinforced concrete column design subjected to biaxial bending.
information on types of beams, different methods to calculate beam stress, design for shear, analysis for SRB flexure, design for flexure, Design procedure for doubly reinforced beam,
Part-I: Seismic Analysis/Design of Multi-storied RC Buildings using STAAD.Pro...Rahul Leslie
For novice, please continue from "Modelling Building Frame with STAAD.Pro & ETABS" (http://www.slideshare.net/rahulleslie/modelling-building-frame-with-staadpro-etabs-rahul-leslie).
This is a presentation covering almost all aspects of Seismic analysis & design of Multi-storied RC Structures using the Indian code IS:1893-2016 (New edition), with references to IS:13920-2015 (Code for ductile detailing) & IS:16700-2017 (code for design of tall buildings) where relevant; following for each aspect of the code, (1) The clause/formula (2) It's explanation/theory (3) How it is/can be implemented in the software packages of (i) STAAD.Pro and (ii) ETABS
This is the latest edition of the earlier slides based on IS:1893-2002 which this one supersedes. This is Part-I of a two part series.
This publication provides a concise compilation of selected rules in the Eurocode 8, together with relevant Cyprus National Annex, that relate to the design of common forms of concrete building structure in the South Europe. It id offers a detail view of the design of steel framed buildings to the structural Eurocodes and includes a set of worked examples showing the design of structural elements with using software (CSI ETABS). It is intended to be of particular to the people who want to become acquainted with design to the Eurocodes. Rules from EN 1998-1-1 for global analysis, type of analysis and verification checks are presented. Detail design rules for steel composite beam, steel column, steel bracing and composite slab with steel sheeting from EN 1998-1-1, EN1993-1-1 and EN1994-1-1 are presented. This guide covers the design of orthodox members in steel frames. It does not cover design rules for regularities. Certain practical limitations are given to the scope.
This document provides details of the analysis and design of a multi-storey reinforced concrete building project. It includes the objectives, which are to analyze and design the main structural elements of the building including slabs, columns, shear walls, and foundations. It also summarizes the building being a 12-storey residential building in Gorakhpur, India. The document outlines the various structural elements that will be designed, including flat slab structural systems, column types and design, shear wall design, and pile foundation design.
The document provides guidance on loads and forces that should be considered when designing bridges, including:
1. Dead loads, live loads, dynamic loads, longitudinal forces, wind loads, centrifugal forces, horizontal water currents, buoyancy, earth pressures, temperature effects, and seismic loads.
2. It describes the various live load models (Class A, B, 70R, AA) and provides details on load intensity, wheel/track configuration, and load combinations.
3. Design recommendations are given for calculating impact factors, braking forces, wind loads, water current pressures, earth pressures, and seismic forces.
Design and analysis of reinforced concrete multistory commercial building usi...Estisharaat Company
Design of multistory building by solving a sample manually ans rest of the building by solving on autodesk robot analysis, complete detailing of r.c members,final year project,complete ,how to design slabs, how to design beams, how to design rc column, how to make final year project, design of stairs,how to design foundations , how to prepare a project before using it in software for analysis,
The document describes designing a simple beam using STAAD.Pro software. It involves generating the beam geometry, applying loads and supports, analyzing the beam, and designing the beam for concrete. Key steps include assigning the beam properties, applying a fixed support at one end and distributed and point loads, obtaining the loading diagram, shear force and bending moment diagrams, and running the concrete design. The output includes structural drawings, input files, concrete takeoff, and beam design details.
This document provides an overview of reinforced concrete design principles for civil engineers and construction managers. It discusses the aim of structural design according to BS 8110, describes the properties and composite action of reinforced concrete, explains limit state design methodology, and summarizes key elements like slabs, beams, columns, walls, and foundations. The document also covers material properties, stress-strain curves, failure modes, and general procedures for slab sizing and design.
This presentation introduces plastic analysis concepts. It discusses stress-strain curves and the difference between elastic and plastic analysis. Key assumptions of plastic analysis are that plane sections remain plane and the stress-strain relationship is identical in compression and tension. Plastic hinges form where the moment equals the plastic moment. Shape factors determine the plastic modulus for different cross-sections. Methods of plastic analysis include static and kinematic approaches. Failure mechanisms involve forming plastic hinges until collapse. Beam examples and problems are provided to demonstrate plastic analysis methods.
American Society of Civil Engineers
Minimum Design Loads for Buildings and Other Structures
2010
--------------------------
Te invito a que visites mis sitios en internet:
_*Canal en youtube de ingenieria civil_*
https://www.youtube.com/@IngenieriaEstructural7
_*Blog de ingenieria civil*_
https://thejamez-one.blogspot.com
23-Design of Column Base Plates (Steel Structural Design & Prof. Shehab Mourad)Hossam Shafiq II
This document discusses the design of column base plates to resist both axial loads and bending moments. It provides equations to calculate stresses on the base plate and footing. It then gives an example of designing a base plate for a column supporting an axial load of 1735 kN and bending moment of 200 kN.m. The design process involves calculating eccentricity, base plate dimensions, stresses on the footing, required plate thickness, and checking bending in two directions. The example concludes by specifying a base plate of dimensions 750mm x 500mm x 40mm that satisfies all design requirements.
Sp 34-1987 handbook on reinforcement and detailingjemmabarsby
This document is a handbook on reinforcement and detailing published by the Bureau of Indian Standards. It provides information on different types of steel used for reinforcement in concrete, including mild steel, medium tensile steel, high strength deformed steel bars, and hard-drawn steel wire fabric. It specifies the requirements for each type of steel in terms of chemical composition, mechanical properties, dimensions and tolerances. The handbook also covers detailing functions, structural drawings, general detailing requirements, bar bending schedules, and detailing of different structural elements like foundations, columns, beams etc.
Introduction-Plastic hinge concept-plastic section modulus-shape factor-redistribution of moments-collapse mechanism.
Theorems of plastic analysis - Static/lower bound theorem; Kinematic/upper bound theorem-Plastic analysis of beams and portal frames by equilibrium and mechanism methods.
International Refereed Journal of Engineering and Science (IRJES)irjes
International Refereed Journal of Engineering and Science (IRJES) is a leading international journal for publication of new ideas, the state of the art research results and fundamental advances in all aspects of Engineering and Science. IRJES is a open access, peer reviewed international journal with a primary objective to provide the academic community and industry for the submission of half of original research and applications
International Refereed Journal of Engineering and Science (IRJES)irjes
International Refereed Journal of Engineering and Science (IRJES) is a leading international journal for publication of new ideas, the state of the art research results and fundamental advances in all aspects of Engineering and Science. IRJES is a open access, peer reviewed international journal with a primary objective to provide the academic community and industry for the submission of half of original research and applications
ANALYSIS AND DESIGN OF HIGH RISE BUILDING BY USING ETABSila vamsi krishna
RESULT OF ANALYSIS:
https://www.slideshare.net/ilavamsikrishna/results-of-etabs-on-high-rise-residential-buildings
ANALYSIS AND DESIGN OF BUILDING BY USING STAAD PRO PPT link :
https://www.slideshare.net/ilavamsikrishna/analysis-and-design-of-mutistoried-residential-building-by-using-staad-pro
FOR FULL REPORT:
vamsiila@gmail.com
The lecture is in support of:
(1) The Design of Building Structures (Vol.1, Vol. 2), rev. ed., PDF eBook by Wolfgang Schueller, 2016
(2) Building Support Structures, Analysis and Design with SAP2000 Software, 2nd ed., eBook by Wolfgang Schueller,
The SAP2000V15 Examples and Problems SDB files are available on the Computers & Structures, Inc. (CSI) website: http://www.csiamerica.com/go/schueller
This document provides an overview of the design of steel beams. It discusses various beam types and sections, loads on beams, design considerations for restrained and unrestrained beams. For restrained beams, it covers lateral restraint requirements, section classification, shear capacity, moment capacity under low and high shear, web bearing, buckling, and deflection checks. For unrestrained beams, it discusses lateral torsional buckling, moment and buckling resistance checks. Design procedures and equations for determining effective properties and capacities are also presented.
The document summarizes the major changes between the 1997 and 1994 versions of the Uniform Building Code (UBC) related to earthquake resistant design. Key changes included expanding the soil profile types from 4 to 6 types dependent on seismic zone, introducing two new structural framing systems, basing seismic design on strength-level rather than service-level, and making the design base shear a function of both horizontal and vertical ground motion components. The 1997 UBC also included simplified methods for determining design base shear in shorter buildings, calculating displacements and drift, and distributing seismic forces.
This document discusses the design of biaxially loaded columns. It defines a biaxially loaded column as one where axial load acts with eccentricities about both principal axes, causing bending in two directions. Several methods for analyzing and designing biaxially loaded columns are presented, including the load contour method, reciprocal load method, strain compatibility method, and equivalent eccentricity method. An example problem demonstrates using the reciprocal load method to check the adequacy of a trial reinforced concrete column design subjected to biaxial bending.
information on types of beams, different methods to calculate beam stress, design for shear, analysis for SRB flexure, design for flexure, Design procedure for doubly reinforced beam,
Part-I: Seismic Analysis/Design of Multi-storied RC Buildings using STAAD.Pro...Rahul Leslie
For novice, please continue from "Modelling Building Frame with STAAD.Pro & ETABS" (http://www.slideshare.net/rahulleslie/modelling-building-frame-with-staadpro-etabs-rahul-leslie).
This is a presentation covering almost all aspects of Seismic analysis & design of Multi-storied RC Structures using the Indian code IS:1893-2016 (New edition), with references to IS:13920-2015 (Code for ductile detailing) & IS:16700-2017 (code for design of tall buildings) where relevant; following for each aspect of the code, (1) The clause/formula (2) It's explanation/theory (3) How it is/can be implemented in the software packages of (i) STAAD.Pro and (ii) ETABS
This is the latest edition of the earlier slides based on IS:1893-2002 which this one supersedes. This is Part-I of a two part series.
This publication provides a concise compilation of selected rules in the Eurocode 8, together with relevant Cyprus National Annex, that relate to the design of common forms of concrete building structure in the South Europe. It id offers a detail view of the design of steel framed buildings to the structural Eurocodes and includes a set of worked examples showing the design of structural elements with using software (CSI ETABS). It is intended to be of particular to the people who want to become acquainted with design to the Eurocodes. Rules from EN 1998-1-1 for global analysis, type of analysis and verification checks are presented. Detail design rules for steel composite beam, steel column, steel bracing and composite slab with steel sheeting from EN 1998-1-1, EN1993-1-1 and EN1994-1-1 are presented. This guide covers the design of orthodox members in steel frames. It does not cover design rules for regularities. Certain practical limitations are given to the scope.
This document provides details of the analysis and design of a multi-storey reinforced concrete building project. It includes the objectives, which are to analyze and design the main structural elements of the building including slabs, columns, shear walls, and foundations. It also summarizes the building being a 12-storey residential building in Gorakhpur, India. The document outlines the various structural elements that will be designed, including flat slab structural systems, column types and design, shear wall design, and pile foundation design.
The document provides guidance on loads and forces that should be considered when designing bridges, including:
1. Dead loads, live loads, dynamic loads, longitudinal forces, wind loads, centrifugal forces, horizontal water currents, buoyancy, earth pressures, temperature effects, and seismic loads.
2. It describes the various live load models (Class A, B, 70R, AA) and provides details on load intensity, wheel/track configuration, and load combinations.
3. Design recommendations are given for calculating impact factors, braking forces, wind loads, water current pressures, earth pressures, and seismic forces.
Design and analysis of reinforced concrete multistory commercial building usi...Estisharaat Company
Design of multistory building by solving a sample manually ans rest of the building by solving on autodesk robot analysis, complete detailing of r.c members,final year project,complete ,how to design slabs, how to design beams, how to design rc column, how to make final year project, design of stairs,how to design foundations , how to prepare a project before using it in software for analysis,
The document describes designing a simple beam using STAAD.Pro software. It involves generating the beam geometry, applying loads and supports, analyzing the beam, and designing the beam for concrete. Key steps include assigning the beam properties, applying a fixed support at one end and distributed and point loads, obtaining the loading diagram, shear force and bending moment diagrams, and running the concrete design. The output includes structural drawings, input files, concrete takeoff, and beam design details.
This document provides an overview of reinforced concrete design principles for civil engineers and construction managers. It discusses the aim of structural design according to BS 8110, describes the properties and composite action of reinforced concrete, explains limit state design methodology, and summarizes key elements like slabs, beams, columns, walls, and foundations. The document also covers material properties, stress-strain curves, failure modes, and general procedures for slab sizing and design.
This presentation introduces plastic analysis concepts. It discusses stress-strain curves and the difference between elastic and plastic analysis. Key assumptions of plastic analysis are that plane sections remain plane and the stress-strain relationship is identical in compression and tension. Plastic hinges form where the moment equals the plastic moment. Shape factors determine the plastic modulus for different cross-sections. Methods of plastic analysis include static and kinematic approaches. Failure mechanisms involve forming plastic hinges until collapse. Beam examples and problems are provided to demonstrate plastic analysis methods.
American Society of Civil Engineers
Minimum Design Loads for Buildings and Other Structures
2010
--------------------------
Te invito a que visites mis sitios en internet:
_*Canal en youtube de ingenieria civil_*
https://www.youtube.com/@IngenieriaEstructural7
_*Blog de ingenieria civil*_
https://thejamez-one.blogspot.com
23-Design of Column Base Plates (Steel Structural Design & Prof. Shehab Mourad)Hossam Shafiq II
This document discusses the design of column base plates to resist both axial loads and bending moments. It provides equations to calculate stresses on the base plate and footing. It then gives an example of designing a base plate for a column supporting an axial load of 1735 kN and bending moment of 200 kN.m. The design process involves calculating eccentricity, base plate dimensions, stresses on the footing, required plate thickness, and checking bending in two directions. The example concludes by specifying a base plate of dimensions 750mm x 500mm x 40mm that satisfies all design requirements.
Sp 34-1987 handbook on reinforcement and detailingjemmabarsby
This document is a handbook on reinforcement and detailing published by the Bureau of Indian Standards. It provides information on different types of steel used for reinforcement in concrete, including mild steel, medium tensile steel, high strength deformed steel bars, and hard-drawn steel wire fabric. It specifies the requirements for each type of steel in terms of chemical composition, mechanical properties, dimensions and tolerances. The handbook also covers detailing functions, structural drawings, general detailing requirements, bar bending schedules, and detailing of different structural elements like foundations, columns, beams etc.
Introduction-Plastic hinge concept-plastic section modulus-shape factor-redistribution of moments-collapse mechanism.
Theorems of plastic analysis - Static/lower bound theorem; Kinematic/upper bound theorem-Plastic analysis of beams and portal frames by equilibrium and mechanism methods.
International Refereed Journal of Engineering and Science (IRJES)irjes
International Refereed Journal of Engineering and Science (IRJES) is a leading international journal for publication of new ideas, the state of the art research results and fundamental advances in all aspects of Engineering and Science. IRJES is a open access, peer reviewed international journal with a primary objective to provide the academic community and industry for the submission of half of original research and applications
International Refereed Journal of Engineering and Science (IRJES)irjes
International Refereed Journal of Engineering and Science (IRJES) is a leading international journal for publication of new ideas, the state of the art research results and fundamental advances in all aspects of Engineering and Science. IRJES is a open access, peer reviewed international journal with a primary objective to provide the academic community and industry for the submission of half of original research and applications
Variation of deflection of steel high rise structure due to p- delta effect c...Yousuf Dinar
This document summarizes the results of a study that analyzed the effect of P-Delta on the deflection of steel high-rise structures considering global slenderness ratio. 40 different structural models were simulated with varying numbers of stories (7, 14, 20, 30) and bay dimensions to modify the slenderness. Both P-Delta analysis and linear static analysis were performed, and deflections were compared. P-Delta analysis resulted in significantly higher deflections than linear static analysis, especially as slenderness increased with taller buildings and smaller bays. Deflections at the top of each structure and for individual stories were evaluated. Results showed increasing deflections with P-Delta analysis as slenderness rose due to building height or
Pushover analysis was performed on a 12-story building model designed for seismic zones 3 and 5 in India. The analysis assessed damage at different performance levels from immediate occupancy to collapse. For the zone 3 design, yielding initially occurred in beams and then columns. The structure remained within collapse prevention limits, indicating ductile behavior. Similarly, the zone 5 design remained ductile with initial yielding in beams and columns. The structures designed using linear analysis for both seismic zones were found to perform well under pushover analysis and experience damage within acceptable limits.
2001 iabse - Reliability Assessment of Cable-Stayed BridgesFranco Bontempi
IABSE Conference on Cable-Supported Bridges
June 12–14, 2001, Seoul, Korea
The paper deals with the reliability assessment of P.C. cable-stayed bridges, but it is thought that the presented methodology is generally applicable. Due to several sources of uncertainties, the geometrical and mechanical properties which define the structural problem cannot be considered as deterministic quantities. In this work, such uncertainties are modelled by using a fuzzy criterion which considers the model parameters bounded between minimum and maximum suitable values.
The reliability problem is formulated in terms of safety factor and the membership function over the failure interval is derived for several limit states by using a simulation technique. In particular, the strategic planning of the simulation is found by means of a genetic optimisation algorithm and the structural analyses are carried out by taking both material and geometrical non-linearity into account. An application to a cable-stayed bridge shows the effectiveness of the proposed procedure.
Effect of P-Delta Due To Different Eccentricities in Tall StructuresIJERA Editor
P-effect in structure mainly rises from the direct action of lateral forces and the structure in a state of equilibrium where the deformed structure shape is a more responsible factor. This kind of effect is made in the analysis of second order, where the geometry of the elements is come from their changed condition. Gravitational loads on the construction elements, deform producing extra forces, which are not taken into account during calculations of structures in un-deformed shape. The given gravitational loads are more precisely defined, in the group of action forces in a structure, can't be said that their change from project values, will be the determining factor in the effect of P-Delta, but in defining order remains the geometry of the structure. More detail the geometry is defined as the correct second order effects could be considered in structures. In this paper static & dynamic analysis has been performed using with and without P-delta for symmetry & asymmetry Reinforced Concrete (RC) frame building models by varying different eccentricities levels from 0, 10, 20 & 30 percent. Results of comparison between symmetrical & Asymmetrical building in zone 4 & 5 are conferred and conclusions are made.
Reliability Assessment of Cable-Stayed BridgesFranco Bontempi
The paper deals with the reliability assessment of P.C. cable-stayed bridges, but it is thought that
the presented methodology is generally applicable. Due to several sources of uncertainties, the
geometrical and mechanical properties which define the structural problem cannot be considered as deterministic quantities. In this work, such uncertainties are modelled by using a fuzzy criterion which considers the model parameters bounded between minimum and maximum suitable values. The reliability problem is formulated in terms of safety factor and the membership function over the
failure interval is derived for several limit states by using a simulation technique. In particular, the strategic planning of the simulation is found by means of a genetic optimisation algorithm and the structural analyses are carried out by taking both material and geometrical non-linearity into
account. An application to a cable-stayed bridge shows the effectiveness of the proposed procedure.
Reliability Assessment of Cable-Stayed BridgesFranco Bontempi
This document discusses a methodology for reliability assessment of cable-stayed bridges that considers uncertainties in geometric and material properties. A case study application to a cable-stayed bridge in Brazil is presented. Non-linear structural analyses are performed through simulation to derive membership functions for safety factors associated with limit states of failure. An optimized sampling method using genetic algorithms is proposed to refine the simulation results and provide more accurate minimum safety factors.
Lecture 2 s. s. iii Design of Steel Structures - Faculty of Civil Engineering...Ursachi Răzvan
This document discusses various types of imperfections that must be considered in structural analysis of steel frames and bracing systems, including:
1) Local imperfections of individual members like residual stresses and geometric imperfections.
2) Global imperfections for frames including initial sway imperfections and local bow imperfections of members. These are accounted for using equivalent geometric imperfections or forces.
3) Imperfections of bracing systems including initial bow imperfections of restrained members, which can also be replaced by equivalent stabilizing forces. Imperfections must also be considered at splice connections.
4) Local bow imperfections are used to determine buckling resistance of individual members. Equivalent forces or loads
Progressive collapse analysis of reinforced concrete framed structureeSAT Journals
This document summarizes a study on progressive collapse analysis of a 12-story reinforced concrete framed structure. The structure was modeled and designed in ETABS software. Progressive collapse was analyzed by removing individual columns and performing linear static analysis according to GSA guidelines. Demand capacity ratios were calculated for members. Results showed that columns met acceptance criteria but some beams adjacent to removed columns had demand capacity ratios over 2.0 and were deemed unsafe. Reinforcement of these beams is recommended to develop alternative load paths and prevent progressive collapse from localized failure.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
P delta effect in reinforced concrete structures of rigid jointYousuf Dinar
ABSTRACT: Popularity of High-Rise structures of rigid joint frame system are increasing day by day to accommodate growing people in metropolitan city and to construct the structures without any special structural component. However combination of rigid frame with RC structure get 30 storey as maximum storey and prone to collapse under severe displacement, axial force and moment, if the P-Delta effects does not included in analysis and design phase. Due to complexity and low knowledge of P-Delta analyses designers, engineers and architectures are prone to perform Linear Static analysis which may eventually become a cause of catastrophic collapse of the high-rise. 12 cases and 2 different analysis are performed to give a light on the P-Delta effect in RC Structures of Rigid Joint which will aware and suggest concerning person to understand, make experience and perform P-Delta analysis of the high-rise for safety using numerical modelling which may accelerate the process and reduce the complexities.
Progressive Collapse Analysis of RC Buildings with consideration of Effect of...ijsrd.com
To study the effect of failure of load carrying elements i.e. columns on the entire structure; 15 storey moment resistant RC buildings is considered. The buildings are modeled and analyzed for progressive collapse using the structural analysis and design software SAP2000. Normally it has been considered only the failure of primary load carrying members like columns, beams, struts, foundations etc. to understand the progressive collapse scenario. This paper involves the effect of slabs in progressive collapse with the failure of column.
P- Delta Effect in Reinforced Concrete Structures of Rigid joint IOSR Journals
Popularity of High-Rise structures of rigid joint frame system are incresing day by day to accommodate growing people in metropoliton city and to construct the structures without any special structural component. However combination of rigid frame with RC structure get 30 storey as maximum storey and prone to collapse under severe displacement, axial force and moment, if the P-Delta effects does not included in analysis and design phase. Due to complexity and low knowledge of P-Delta analyses designers, engineers and architectures are prone to perform Linear Static analysis which may eventually become a cause of catastropic collapse of the high-rise. 12 cases and 2 different analysis are performed to give a light on the P-Delta effect in RC Structures of Rigid Joint which will aware and suggest concering person to understand, make experience and perform P-Delta analysis of the high-rise for safety using numeriacal modelling which may accelerate the process and reduce the complexities.
Capacity Spectrum Method for RC Building with Cracked and Uncracked SectionIOSR Journals
one of the most widespread procedures for the assessment of building behavior, due to earthquake, is the Capacity Spectrum Method (CSM). In the scope of this procedure, capacity of the structure compares with the demands of earthquake ground motion on the structure. The capacity of the structure is represented by a nonlinear force-displacement curve, referred to as a pushover curve. The base shear forces and roof displacements are converted to equivalent spectral accelerations and spectral displacements, respectively, by means of coefficients that represent effective modal masses and modal participation factors. These spectral values define the capacity spectrum. The demands of the earthquake ground motion are represented by response spectra. A graphical construction that includes both capacity and demand spectra, results in an intersection of the two curves that estimates the performance of the structure to the earthquake. In this study, for determination of the performance levels, G+10 R.C.C. Building with cracked and uncracked section were taken. The structural Capacity of cracked and uncracked section compared with performance point value, which shows the structural capacity of building having cracked section is lesser than the uncracked section. Different modeling issues were analyzed to study the effect on Capacity of the structure with cracked and uncracked section for different position of Shear wall.
IRJET- Seismic Analysis of Steel Frame Building using Bracing in ETAB SoftwareIRJET Journal
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Effectiveness Evaluation of Seismic Protection Devices for Bridges in the PB...Franco Bontempi
Seismic protection measures for bridges can be used both for obtaining acceptable performances from new structures that for retrofitting existing ones. With the modern design philosophy based on probabilistic Performance-Based Earthquake Engineering (PBEE) approaches, the engineers are allowed to investigate different design solutions in terms of vulnerability assessment. However, if probabilistic PBEE approaches are nowadays well established and widely studied also for bridges, the topic of using the PBEE frameworks for the evaluation of the effectiveness of seismic protection devices for bridges is not extensively treated in literature.
The first objective of this work is to deal with the problem of assessing the earthquake performance of an highway bridge equipped with different bearing device: the
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Summary of CHAPTER 6 (ACI318-14M) Structural Analysis
1. SUMMARY OF CH 6 ACI318-14
Structural Analysis
BY: ABDULLAH ABDULRAHMAN KHAIR
2. Structural Analysis on ACI318-14 By Abdullah Khair
Page | 1
Summary of CHAPTER 6 (ACI318-14M)
Structural Analysis
By: Abdullah Abdulrahman Khair
6.1 this chapter shall apply to methods of analysis, modeling of members and structural
systems, and calculation of load effects.
6.2.3 Methods of analysis permitted by this chapter shall be (a) through (e):
(a) The simplified method for analysis of continuous beams and one-way slabs for
gravity loads
(b) First-order
(c) Elastic second-order in
(d) Inelastic second-order
(e) Finite element
Commentary on 6.2.3
first-order analysis satisfies the equations of equilibrium using the original undeformed
geometry of the structure. When only first-order results are considered, slenderness effects
are not accounted for. Because these effects can be important, 6.6 provides procedures
to calculate both individual member slenderness (Pδ) effects and sidesway (P∆) effects
for the overall structure using the first-order results.
A second-order analysis satisfies the equations of equilibrium using the deformed
geometry of the structure. If the second-order analysis uses nodes along compression
members, the analysis accounts for slenderness effects due to lateral deformations along
individual members, as well as sidesway of the overall structure. If the second-order
analysis uses nodes at the member intersections only, the analysis captures the sidesway
effects for the overall structure but neglects individual member slenderness effects. In this
case, the moment magnifier method (6.6.4) is used to determine individual member
slenderness effects.
3. Structural Analysis on ACI318-14 By Abdullah Khair
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What is P-delta effect?
P-delta effect is secondary effect on structure. It is also known as ‘Geometric nonlinearity
effect’. As number of stories increases, P-delta effect becomes more important. If the
change in bending moments and displacements is more than 10%, P-delta effect should
be considered in design.
There are two distinct types of P-delta effects: P-∆ (sometimes referred to as “large P
delta” or “P-large delta”) and P-δ (sometimes referred to as “small P-delta” or “P-small
delta”):
P-∆ has reference to the effects of the vertical loads acting on the laterally displaced
structure. For example, wind or seismic forces, V, cause a horizontal displacement, ∆, of
the structure, while the gravity loads, P, simultaneously act vertically on this displaced
structure. Moments are induced into the structure equal to the total vertical load P times
the structural displacement ∆.
P-δ has reference to the effects of the axial load in an individual member subject to a
deflection (curvature) between its endpoints. For example, column loads, P, due to
gravity, wind, and/or seismic forces act on a column that has a curvature induced by
the connection conditions of supported beams. Moments are induced in the member
proportional to the axial load P times the member deflection δ. Note that axially loaded
beams also experience these effects.
4. Structural Analysis on ACI318-14 By Abdullah Khair
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In conventional first order structural analysis, the equilibrium is expressed in terms of the
geometryof the un-deformed structure. In case of linearly elastic structure, relation
between displacement and external force is proportional. In addition, stress-strain
relationship of material is linear. Thus, by definition, this method excludes nonlinearity, but
it generally represents conditions at service loads very well. The first order elastic analysis
is based on following assumptions: -
(1) Material behaves linearly and hence all yielding effect can be ignored.
(2) The member behaves linearly, and the member instability effect such as those caused
by axial compression (these are called P-δ effects), which reduces the member’s flexural
stiffness, can be ignored.
(3) The frame also behaves linearly, and the frame instability effects, such as those
caused by the moments due to horizontal frame deflection and gravity loads acting on
the displaced structure (these are called P-∆ effects), can be ignored.
Though the first–order elastic analysis provides an ‘exact solution’ that satisfies the
requirements of compatibility and equilibrium of the un-deformed structure, it does not
provide any information about the influence of plasticity and stability on the behavior of
the structure. Hence, these influences are normally provided indirectly in member
capacity checks.
A first-order elastic analysis is sufficient for normal framed structures, which are braced
against sway, however, first-order elastic analysis will not yield sufficiently accurate results
for some suspension systems, arches, tall buildings, and structure subjected to early
localized yielding or cracking. All the structure exhibit significant non-linear response just
prior to reaching their limit of resistance because of yielding and buckling effects
associated with axial compressive forces. Hence, this nonlinear behavior is accounted
for by the code formulae (that makes allowance for non-linearity in some empirical or
semi-empirical manner) or by supplementary theoretical or experimental studies. Second
order effects on the frame are accounted by a combination of P-∆ effect, which
corresponds to overall frame, and P-δ effect, which corresponds to individual members
within the frame. Since both of these contribute to the deformation of the frame it is
important to consider their combined effect.
6. Structural Analysis on ACI318-14 By Abdullah Khair
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6.3 Modeling assumptions
Relative stiffnesses of members within structural systems shall be based on reasonable
and consistent assumptions.
Ideally, the member stiffnesses EcI and GJ should reflect the degree of cracking and
inelastic action that has occurred along each member before yielding.
To calculate moments and shears caused by gravity loads in columns, beams, and slabs,
it shall be permitted to use a model limited to the members in the level being considered
and the columns above and below that level. It shall be permitted to assume far ends of
columns built integrally with the structure to be fixed.
The analysis model shall consider the effects of variation of member cross-sectional
properties, such as that due to haunches. (Stiffness and fixed-end moment coefficients
for haunched members may be obtained from the Portland Cement Association (1972)).
6.5 Simplified method of analysis for nonprestressed continuous beams and one-way
slabs
It shall be permitted to calculate Mu and Vu due to gravity loads in accordance with this
section for continuous beams and one-way slabs satisfying (a) through (e):
(a) Members are prismatic
(b) Loads are uniformly distributed
(c) L ≤ 3D
(d) There are at least two spans
(e) The longer of two adjacent spans does not exceed the shorter by more than 20
percent
7. Structural Analysis on ACI318-14 By Abdullah Khair
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The approximate moments and shears give reasonable values for the stated conditions
if the continuous beams and one-way slabs are part of a frame or continuous
construction. Because the load patterns that produce critical values for moments in
columns of frames differ from those for maximum negative moments in beams, column
moments should be evaluated separately.
Floor or roof level moments shall be resisted by distributing the moment between columns
immediately above and below the given floor in proportion to the relative column
stiffnesses considering conditions of restraint.
6.6 First-order analysis
When using first-order analysis, slenderness effects are calculated using the moment
magnifier approach
Redistribution of moments calculated by an elastic first-order analysis shall be reduction
of moments at sections of maximum negative or maximum positive moment calculated
by elastic theory shall be permitted for any assumed loading arrangement if (a) and (b)
are satisfied:
(a) Flexural members are continuous
(b) εt≥ 0.0075at the section at which moment is reduced
6.6.2 Modeling of members and structural systems
Floor or roof level moments shall be resisted by distributing the moment between columns
immediately above and below the given floor in proportion to the relative column
stiffnesses and considering conditions of restraint.
For frames or continuous construction, consideration shall be given to the effect of floor
and roof load patterns on transfer of moment to exterior and interior columns, and of
eccentric loading due to other causes
It shall be permitted to simplify the analysis model by the assumptions of (a), (b), or both:
(a) Solid slabs or one-way joist systems built integrally with supports, with clear spans not
more than 3 m, shall be permitted to be analyzed as continuous members on knife-edge
supports with spans equal to the clear spans of the member and width of support beams
otherwise neglected.
(b) For frames or continuous construction, it shall be permitted to assume the intersecting
member regions are rigid.
8. Structural Analysis on ACI318-14 By Abdullah Khair
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6.6.3 Section properties
Factored load analysis for lateral load analysis, either the stiffnesses presented in 6.6.3.1.1
or 6.6.3.1.2 can be used. These provisions both use values that approximate the stiffness
for reinforced concrete building systems loaded to near or beyond the yield level, and
have been shown to produce reasonable correlation with both experimental and
detailed analytical results (Moehle 1992; Lepage 1998). For earthquake-induced loading,
the use of 6.6.3.1.1 or 6.6.3.1.2 may require a deflection amplification factor to account
for inelastic deformations. In general, for effective section properties, Ec may be defined
as in 19.2.2, A as in Table 6.6.3.1.1(a), and the shear modulus may be taken as 0.4Ec
Moment of inertia and cross-sectional area of members shall be calculated in
accordance with Tables 6.6.3.1.1(a) or 6.6.3.1.1(b), unless a more rigorous analysis is used.
If sustained lateral loads are present, I for columns and walls shall be divided by (1 + βds),
where βds is the ratio of maximum factored sustained shear within a story to the maximum
factored shear in that story associated with the same load combination.
.
For factored lateral load analysis, it shall be permitted to assume I = 0.5Igfor all members
or to calculate I by a more detailed analysis, considering the reduced stiffness of all
members under the loading conditions.
9. Structural Analysis on ACI318-14 By Abdullah Khair
Page | 8
6.6.4 Slenderness effects, moment magnification method
6.6.4.1 Unless 6.2.5 is satisfied, columns and stories in structures shall be designated as
being nonsway or sway. Analysis of columns in nonsway frames or stories shall be in
accordance with 6.6.4.5. Analysis of columns in sway frames or stories shall be in
accordance with 6.6.4.6.
The cross-sectional dimensions of each member used in an analysis shall be within 10
percent of the specified member dimensions in construction documents or the analysis
shall be repeated. If the stiffnesses of Table 6.6.3.1.1(b) are used in an analysis, the
assumed member reinforcement ratio shall also be within 10 percent of the specified
member reinforcement in construction documents.
It shall be permitted to analyze columns and stories in structures as nonsway frames if (a)
or (b) is satisfied:
(a) The increase in column end moments due to second order effects does not exceed
5 percent of the first-order end moments
(b) Qin accordance with 6.6.4.4.1 does not exceed 0.05
6.6.5 Redistribution of moments in continuous flexural members
6.6.5.1Except where approximate values for moments are used in accordance with 6.5,
where moments have been calculated in accordance with 6.8, or where moments in
two-way slabs are determined using pattern loading specified in 6.4.3.3, reduction of
moments at sections of maximum negative or maximum positive moment calculated by
elastic theory shall be permitted for any assumed loading arrangement if (a) and (b) are
satisfied:
(a) Flexural members are continuous
(b) εt≥ 0.0075at the section at which moment is reduced
6.6.5.2 For prestressed members, moments include those due to factored loads and those
due to reactions induced by prestressing.
6.6.5.3 At the section where the moment is reduced, redistribution shall not exceed the
lesser of 1000εt percent and 20 percent.
6.6.5.4 The reduced moment shall be used to calculate redistributed moments at all other
sections within the spans such that static equilibrium is maintained after redistribution of
moments for each loading arrangement.
6.6.5.5 Shears and support reactions shall be calculated in accordance with static
equilibrium considering the redistributed moments for each loading arrangement
10. Structural Analysis on ACI318-14 By Abdullah Khair
Page | 9
6.7 Elastic second-order analysis
General—In elastic second-order analyses, the deformed geometry of the structure is
included in the equations of equilibrium so that P∆ effects are determined. The structure
is assumed to remain elastic, but the effects of cracking and creep are considered by
using a reduced stiffness EI. In contrast, elastic first-order analysis satisfies the equations of
equilibrium using the original undeformed geometry of the structure and estimates P∆
effects by magnifying the column-end sway moments
An elastic second-order analysis shall consider the influence of axial loads, presence of
cracked regions along the length of the member, and effects of load duration. These
considerations are satisfied using the cross-sectional properties
11. Structural Analysis on ACI318-14 By Abdullah Khair
Page | 10
The stiffnesses EI used in an analysis for strength design should represent the stiffnesses of
the members immediately prior to failure. This is particularly true for a second-order
analysis that should predict the lateral deflections at loads approaching ultimate. The EI
values should not be based solely on the moment-curvature relationship for the most
highly loaded section along the length of each member. Instead, they should
correspond to the moment-end rotation relationship for a complete member
Slenderness effects along the length of a column shall be considered. It shall be
permitted to calculate these effects
The cross-sectional dimensions of each member used in an analysis to calculate
slenderness effects shall be within 10 percent of the specified member dimensions in
construction documents or the analysis shall be repeated.
Alternatively, it shall be permitted to calculate immediate deflections using a moment of
inertia of 1.4 times I given in 6.6.3.1, or calculated using a more detailed analysis, but the
value shall not exceed Ig.
6.8 Inelastic second-order analysis
An inelastic second-order analysis shall consider material nonlinearity, member curvature
and lateral drift, duration of loads, shrinkage and creep, and interaction with the
supporting foundation.
An inelastic second-order analysis procedure shall have been shown to result in
prediction of strength in substantial agreement with results of comprehensive tests of
statically indeterminate reinforced concrete structures.
The cross-sectional dimensions of each member used in an analysis to calculate
slenderness effects shall be within 10 percent of the specified member dimensions in
construction documents or the analysis shall be repeated.
Redistribution of moments calculated by an inelastic second-order analysis shall not be
permitted.
6.9 Acceptability of finite element analysis
his section was introduced in the 2014 Code to explicitly recognize a widely used analysis
method.
The finite element model shall be appropriate for its intended purpose.
The licensed design professional should ensure that an appropriate analysis model is used
for the particular problem of interest. This includes selection of computer software
program, element type, model mesh, and other modeling assumptions.
12. Structural Analysis on ACI318-14 By Abdullah Khair
Page | 11
For inelastic analysis, a separate analysis shall be performed for each factored load
combination.
For inelastic finite element analysis, the rules of linear superposition do not apply. To
determine the ultimate member inelastic response, for example, it is not correct to
analyze for service loads and subsequently combine the results linearly using load factors.
A separate inelastic analysis should be performed for each factored load combination.
The licensed design professional shall confirm that the results are appropriate for the
purposes of the analysis.
The cross-sectional dimensions of each member used in an analysis shall be within 10
percent of the specified member dimensions in construction documents or the analysis
shall be repeated.
Redistribution of moments calculated by an inelastic analysis shall not be permitted.