The document discusses bolted connections in steel structures. It covers various types of bolts used in structural connections, including unfinished bolts, high-strength bolts, and anchor rods. It describes methods for pre-tensioning high-strength bolts, requirements for bolt hole sizes and spacing, and factors that influence the failure of bolted joints. The document also summarizes design considerations and examples for bolted joints subjected to axial forces, eccentric shear forces, shear and tension forces, and tension loads.
Basic concept of fits and tolerances and their practical use in fitment of anti friction bearings and couplings
Machine design and maintenance engineers do encounter the problem in deciding right kind of fitment while assembling various machine elements. Satisfactory functioning of a machine is very much dependent on use of right type of fitment between its various machine elements ( parts). Below is link to a presentation wherein I have tried to summarize the basic concepts of fits and tolerances and their practical use in fitment of rolling contact bearings and coupling
Design of steel structure as per is 800(2007)ahsanrabbani
It does not offer resistance against rotation and also termed as a hinged or pinned connections.
It transfers only axial or shear forces and it is not designed for moment
It is generally connected by single bolt/rivet and therefore full rotation is allowed
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
More Related Content
Similar to Lecture 7 bolted connections-students.pdf
Basic concept of fits and tolerances and their practical use in fitment of anti friction bearings and couplings
Machine design and maintenance engineers do encounter the problem in deciding right kind of fitment while assembling various machine elements. Satisfactory functioning of a machine is very much dependent on use of right type of fitment between its various machine elements ( parts). Below is link to a presentation wherein I have tried to summarize the basic concepts of fits and tolerances and their practical use in fitment of rolling contact bearings and coupling
Design of steel structure as per is 800(2007)ahsanrabbani
It does not offer resistance against rotation and also termed as a hinged or pinned connections.
It transfers only axial or shear forces and it is not designed for moment
It is generally connected by single bolt/rivet and therefore full rotation is allowed
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Cosmetic shop management system project report.pdf
Lecture 7 bolted connections-students.pdf
1. 5/20/2022
1
STEEL STRUCTURES
BOLTED CONNECTIONS
Dr Sarmad Shakeel
sshakil@nice.nust.edu.pk
1
AISI/SAE STEELS
2
• First digit
• The second digit of the series indicates the
concentration of the major element in
percentiles (1 equals 1%).
• The last two digits of the series indicate the
carbon concentration to 0.01%.
AISI/SAE STEELS
3
AISI/SAE STEELS
4
AISI/SAE STEELS
5
TYPE OF BOLTS
Un finished bolts (ordinary or common bolts)
• A307 steel same as A36.
• Diameter: ½ to 1 ½ inches (increments of 1/8)
• Light structures and simple applications like purlins,
bracings,…)
High strength bolts
• A325 or A490 (Diameter: <=1 ½ inches)
• A449 bolts or A354 threaded rods
• Anchor rods F1554
6
Rivet or bolts
• Cost (equipment, high strength)
• Seismic performance
• Labour (number and skills)
• Fire performance
• Dissemblance
1 2
3 4
5 6
2. 5/20/2022
2
• Snug tight bolts
• Pre-tensioned bolts (70% of the yielding stress)-Seismic, fatigue loadings
• Slip critical bolts (same as pre tensioned except treatment of contact or fraying
surfaces) -only required when you have shear or combine shear or tension
Section J of AISC commentary guides you when you have to do the pre tensioning
7
HIGH STRENGTH BOLTS
AISC Specification Section J
Methods for full pre tensioning (70% of tensile yielding stress)
1. Turn of the nut method (one third to one full turn following snug tight
condition)
8
HIGH STRENGTH BOLTS
AISC Manual 16.2 Section 8
Methods for full pre tensioning (70% of tensile yielding stress)
2. Calibrated wrench method
3. Direct tension indicator
4.Twist off bolts
9
HIGH STRENGTH BOLTS
Size of bolt holes
• Standard holes: 1/16 greater than the bolt dia.
• Oversized hole: greater construction tolerances. Not permitted for bearing type
connections
• Short and long slotted holes
• Section J3.2 of specification guides on which hole to use.
10
HIGH STRENGTH BOLTS
AISC Specification Section J
Forces passing through the centre of gravity
Single shear or bearing connections (Forces overcoming the slip resistance)
Lap Joint (Centre of gravity of forces are not aligned resulting in couple which can
cause plates to bend)
11
BOLTED JOINTS SUBJECTED TO AXIAL FORCES
Forces passing through the centre of gravity
Double shear or bearing connections (Forces overcoming the slip resistance)
Butt Joint (More capacity due to two shear planes, more symmetrical loading)
12
BOLTED JOINTS SUBJECTED TO AXIAL FORCES
7 8
9 10
11 12
3. 5/20/2022
3
Forces passing through the centre of gravity
Single shear or bearing connections (Forces overcoming the slip resistance)
Double plane connections (No bending moments)
13
BOLTED JOINTS SUBJECTED TO AXIAL FORCES
14
FAILURE OF BOLTED JOINTS
AISC Specification Section J3.3
To ensure bearing strength
15
SPACING AND EDGE DISTANCE REQUIREMENTS
AISC Specification Section J3.4
To avoid damage during hole punching and end tearing
16
SPACING AND EDGE DISTANCE REQUIREMENTS
• The distance from the center of an oversized or slotted hole to an edge of a
connected part shall be not less than that required for a standard hole to an edge of
a connected part plus the applicable increment, C2, from Table J3.5 or Table
J3.5M.
AISC Specification Section J3.4
17
SPACING AND EDGE DISTANCE REQUIREMENTS
AISC Specification Section J3.5
To prevent moisture from entering joint locations
18
SPACING AND EDGE DISTANCE REQUIREMENTS
13 14
15 16
17 18
4. 5/20/2022
4
Assumptions: Loads passing through C. O. G (Centre of Gravity) exceeding the slip
resistance between the plates shear and bearing at bolts
Shear Strength
AISC Specification Section J3.6
For double shear strength is twice
19
BEARING TYPE CONNECTIONS-LOAD VIA C.O.G
Shear Strength
AISC Specification Section J3.6
20
BEARING TYPE CONNECTIONS-LOAD VIA C.O.G
Bearing Strength
AISC Specification Section J3.10
21
BEARING TYPE CONNECTIONS-LOAD VIA C.O.G
Shear Strength
AISC Specification Section J3.6
22
BEARING TYPE CONNECTIONS-LOAD VIA C.O.G
0.25 in def.
Design
consideration
Shear Strength
AISC Specification Section J3.6
23
BEARING TYPE CONNECTIONS-LOAD VIA C.O.G
• Slip critical connections are only used in case when slip could cause significant
deformations or instability in the structure
• Common application of slip critical connections- connections with over sized
holes or slotted holes
• How to make slip critical connections- use pre tensioned or slip critical bolts
24
SLIP CRITICAL CONNECTIONS-LOAD VIA C.O.G
19 20
21 22
23 24
5. 5/20/2022
5
Slip resistance
AISC Specification Section J3.8
25
SLIP CRITICAL CONNECTIONS-LOAD VIA C.O.G
Slip resistance
AISC Specification Section J3.8
Fraying surfaces defined in Section 3 part 16.2 of AISC
Manual
26
SLIP CRITICAL CONNECTIONS-LOAD VIA C.O.G
Slip resistance
AISC Specification Section J3.8
27
SLIP CRITICAL CONNECTIONS-LOAD VIA C.O.G
28
EXAMPLES
Checks to be performed
• Gross section yielding of the plates
• Tensile rupture strength of the plates
• Bearing strength of the plates
• Shearing strength of the bolts
29
EXAMPLES
• Column cover plates need to resist longitudinal shear
30
EXAMPLES
25 26
27 28
29 30
7. 5/20/2022
7
37
EXAMPLES
38
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Subjected to shear and bending moments
Centre of gravity of loads not aligned with C.O.G of the bolts
39
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Subjected to shear and bending moments
AISC Specification does not give the procedure for their analysis.Three methods
are available in general for their analysis
• Elastic method (Most conservative)
• Reduced or effective eccentricity methods
• Instantaneous centre of rotation method
40
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Elastic analysis
Friction or slip resistance between connected parts is neglected.
Bolts are taken as elastic while connected parts are taken as rigid
41
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Elastic analysis
Magnitude of forces in bolts due to moment Pe
42
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Elastic analysis
37 38
39 40
41 42
8. 5/20/2022
8
43
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Elastic analysis
44
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Elastic analysis
45
EXAMPLE
46
EXAMPLE
47
EXAMPLE
48
EXAMPLE
43 44
45 46
47 48
9. 5/20/2022
9
49
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Reduced eccentricity method
Takes into account the affect of slip resistance of fraying or contacting surfaces using
modified eccentricity for elastic analysis
50
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Instantons centre of rotation method (Used by AISC manual)
Takes into account the affect of inelastic behaviour of bolts
51
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Instantons centre of rotation method (Used by AISC manual)
• Point O, Sum of horizontal components of R must be zero and the moments
caused by these horizontal components about point O should be zero
• Moment of eccentric load about point O should be equal to sum of moments of
Resisting forces R about point O.
• For correct O, sum of vertical components of R must be equal to Pu
∆ is the total deformation of the bolt and
its maximum value for A325 bolt is 0.34
in
52
EXAMPLE
53
EXAMPLE
54
EXAMPLE
49 50
51 52
53 54
10. 5/20/2022
10
55
BOLTS SUBJECTED TO ECCENTRIC SHEAR
Instantons centre of rotation method (Used by AISC manual)
Applying hit and trial process for inclined loads and unsymmetrical bolt arrangements
would even be more difficult by hand
If situation does not fit in the table presented in part 7 of the manual, use elastic analysis
56
EXAMPLE
57
EXAMPLE
58
EXAMPLE
59
EXAMPLE
60
EXAMPLE
55 56
57 58
59 60
11. 5/20/2022
11
61
BOLTS SUBJECTED TO SHEAR AND TENSION
Elliptical interaction curve
62
BOLTS SUBJECTED TO SHEAR AND TENSION
AISC A360 Section J3.7
63
BOLTS SUBJECTED TO SHEAR AND TENSION
64
EXAMPLE
65
EXAMPLE
66
EXAMPLE
61 62
63 64
65 66
12. 5/20/2022
12
67
BOLTS SUBJECTED TO SHEAR AND TENSION (SLIP CRITICAL
CONNECTIONS
AISC A360 Section J3.9
68
TENSION LOADS ON BOLTED JOINT
Effect of pre tensioning??
AISC A360 Section J3.6
69
TENSION LOADS ON BOLTED JOINT
Prying action
70
TENSION LOADS ON BOLTED JOINT
Prying action
AISC Manual Table 7-15
71
TENSION LOADS ON BOLTED JOINT
Prying action
AISC Manual Chapter 9
THANK YOU
Dr Sarmad Shakeel
72
67 68
69 70
71 72