By Shri Nilesh V. Prajapati & Shri S.K.Patel
at 31st National Convention of Civil Engineers
organised by
Gujarat State Center, The Institution of Engineers (India) at Ahmedabad
Introduction about Repair & Rehabilitation of Structures
Repair of Structures
Rehabilitation of Structures
Maintenance of Structures
Various Methods of Maintenance
Because of torsion, the beam fails in diagonal tension forming the spiral cracks around the beam. Warping of the section does not allow a plane section to remain as plane after twisting. Clause 41 of IS 456:2000 provides the provisions for
the design of torsional reinforcements. The design rules for torsion are based on the equivalent moment.
Introduction about Repair & Rehabilitation of Structures
Repair of Structures
Rehabilitation of Structures
Maintenance of Structures
Various Methods of Maintenance
Because of torsion, the beam fails in diagonal tension forming the spiral cracks around the beam. Warping of the section does not allow a plane section to remain as plane after twisting. Clause 41 of IS 456:2000 provides the provisions for
the design of torsional reinforcements. The design rules for torsion are based on the equivalent moment.
Steel column design plays a crucial role in the construction industry, ensuring the structural integrity and safety of buildings and infrastructure projects. Columns are vertical load-bearing members that support the weight of the structure and transmit it to the foundation. This brief presentation provides an overview of steel column design, highlighting key considerations, design principles, and the importance of adherence to codes and standards.
non destructive concrete testing equipment
non destructive concrete testing methods
non destructive test Penetration method
Rebound hammer method
Pull out test method
Ultrasonic pulse velocity method
Radioactive methods
methods of testing concrete
concrete strength testing methods
types of non destructive testing
non destructive concrete testing equipment
concrete tests pdf
destructive and non destructive testing
concrete testing procedures
non destructive test for concrete
destructive and non destructive testing
non destructive testing pdf
types of non destructive testing
non destructive testing methods
non destructive testing methods ppt
Description about demolition of building, what is demoltion and how it is different from deconstruction. What are the method of Demolition and how demolition is crried out in a site. Phase of Demoliton. Safety precaution during Demolition etc.
RESTORATION OF EXISTING MAJOR BRIDGE ACROSS RIVER BHADAR ON NATIONAL HIGHWAY ...IEI GSC
By S.K.Patel, P C Gandhi S R Shah J N Prajapati
at 31st National Convention of Civil Engineers
organised by
Gujarat State Center, The Institution of Engineers (India) at Ahmedabad
Diaphragm wall: Construction and DesignUmer Farooq
Diaphragm walls are concrete or reinforced concrete walls constructed in slurry-supported, open trenches below existing ground.
Concrete is placed using the Tremie installation method or by installing pre-cast concrete panels (known as a pre-cast diaphragm wall). Diaphragm walls can be constructed to depths of 150 meters and to widths of 0.5 to 1.50 meters.
Steel column design plays a crucial role in the construction industry, ensuring the structural integrity and safety of buildings and infrastructure projects. Columns are vertical load-bearing members that support the weight of the structure and transmit it to the foundation. This brief presentation provides an overview of steel column design, highlighting key considerations, design principles, and the importance of adherence to codes and standards.
non destructive concrete testing equipment
non destructive concrete testing methods
non destructive test Penetration method
Rebound hammer method
Pull out test method
Ultrasonic pulse velocity method
Radioactive methods
methods of testing concrete
concrete strength testing methods
types of non destructive testing
non destructive concrete testing equipment
concrete tests pdf
destructive and non destructive testing
concrete testing procedures
non destructive test for concrete
destructive and non destructive testing
non destructive testing pdf
types of non destructive testing
non destructive testing methods
non destructive testing methods ppt
Description about demolition of building, what is demoltion and how it is different from deconstruction. What are the method of Demolition and how demolition is crried out in a site. Phase of Demoliton. Safety precaution during Demolition etc.
RESTORATION OF EXISTING MAJOR BRIDGE ACROSS RIVER BHADAR ON NATIONAL HIGHWAY ...IEI GSC
By S.K.Patel, P C Gandhi S R Shah J N Prajapati
at 31st National Convention of Civil Engineers
organised by
Gujarat State Center, The Institution of Engineers (India) at Ahmedabad
Diaphragm wall: Construction and DesignUmer Farooq
Diaphragm walls are concrete or reinforced concrete walls constructed in slurry-supported, open trenches below existing ground.
Concrete is placed using the Tremie installation method or by installing pre-cast concrete panels (known as a pre-cast diaphragm wall). Diaphragm walls can be constructed to depths of 150 meters and to widths of 0.5 to 1.50 meters.
Performance Based Evaluation of Shear Walled RCC Building by Pushover AnalysisIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
Comparative Study of Analysis of G 6 Building for Different Seismic Zones usi...ijtsrd
STAAD and ETABS are today the markets leading design software. This latest encoded software is used by many design companies. As a result, this project development mainly addresses virtual analysis of the results achieved by designing a multi story concrete frame design when designed on a separate basis using STAAD and ETAB software. The design consists of load calculations and analysis of the entire structure. STAAD.Pros and ETABSs design methods are limited state designs in compliance with the Indian Standard Practice Code. The principal aim of the structural engineers is to develop a safe and economical structure using technologies to make it more complicated and large structures for the structural engineer to tackle. STAAD.pro offers state of the art visualisation tools and powerful, dynamic analytical analytical and design engines. STAAD.Pro is the choice of a professional from the generation of the model, analysis and design to the viewing and verification of results. ETABS is currently used by many structural designers as well as a leading design software. Subhangi. R. Meshram | Prof. G. D. Dhawale | Prof. V. A. Kalmegh "Comparative Study of Analysis of G+6 Building for Different Seismic Zones using STAAD.PRO and ETABS - A Review" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd42583.pdf Paper URL: https://www.ijtsrd.comengineering/structural-engineering/42583/comparative-study-of-analysis-of-g6-building-for-different-seismic-zones-using-staadpro-and-etabs--a-review/subhangi-r-meshram
Comparative study on multistoried building using linear and non linear analysisIJARIIT
The effect of infill walls on the building is generally neglected in the analysis. In fact, an infill wall contributes to the
lateral strength and stiffness of the structure. Seismic response analysis of multi storey building frame with infill was done by
modeling the infill wall as an equivalent diagonal strut. For the equivalent diagonal strut, the thickness is taken equal to the
thickness of the wall and width of the strut as per “Equivalent strut method”. The comparison of seismic responses is done for
the multi-storied buildings with infill as equivalent diagonal strut using linear and non-linear analysis. ETABS software is used
for the present study.
Analysis of G+7 Multistoried Building for Various Locations of Shear Wall Con...ijceronline
Dynamic Analysis of a 8-storey building is done in this research paper and for this a irregular building has been taken into consideration. The research paper also considers the effect of change in the position of shear wall in the building plan and its effect on the structure during the analysis. Overall 8 cases of the various positions of shear wall has been considered separately and the comparative results has been seen. The building which we have taken for analysis is of irregular shape resembling the letter “L” in plan and has a height of 28.8 m. The dimensions are 25m along x direction and 30m along z direction. STAAD Pro v8i has been used for the dynamic analysis of 8 storied building. The analysis has taken into consideration the effect of torsion also and have been analysed as per IS 1893(Part 1): 2002. The building structure is considered to be made of M-20 grade concrete and Fe-415 grade steel. The factors considered for comparison are Peak storey Shear along both directions, Peak storey Shear along both directions considering torsion, Average Displacement along both directions and Drift along both directions. The structure considered is in Zone III in medium soil.
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Presentation on DIAGNOSTIC ANALYSIS OF DISTRESSED HYDRAULIC STRUCTURES: CASE STUDIES OF GUJARAT, INDIA by Er Vivek P Kapadiya, Chief Engineer & Additional Secretary, Government of Gujarat at #33NCCE #IEIGSC
Flexure Behaviour of Ferrocement Strengthened RC beamsIEI GSC
Presentation on Flexure Behaviour of Ferrocement Strengthened RC beams
made by Axay Dhariwal under guidance of Prof Sunil Raiyani, Nirma Institute of Technology at #33NCCE #IEIGSC
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Presentation on Laboratory Investigation on the Mechanical Behavior of Concrete Containing Steel Industry Waste made by Damyanti Baghada under supervision of Dr C D Modhera, SVNIT at #33NCCE #IEIGSC
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Presentation on ENHANCEMENT OF SEISMIC PERFORMANCE OF STRUCTURES USING HyFRC by Needhi Kotoky Under the supervision of Dr. Anjan Dutta and Dr. Sajal K. Deb Department of Civil EngineeringIndian Institute of Technology Guwahati
Prefabricated construction systems in India- Precast Status and needed ImpetusIEI GSC
Presentation on Prefabricated construction systems in India- Precast Status and needed Impetus by Prof S. K. Singh,Sr. Principal Scientist & Professor, AcSIR, CSIR-Central Building Research Institute, Roorkee at #33NCCE 33rd National Convention of Civil Engineers at #IEIGSC
Evaluation of durability properties of recycled aggregate concrete incorporat...IEI GSC
Presentation on Evaluation of durability properties of recycled aggregate concrete incorporating flyash and silica fume by Parth Patel, Guided by Dr Urmil Dave & Prof Tejas Joshi, Nirma University, Ahmedabad at #33NCCE 33rd National Convention of Civil Engineers at #IEIGSC
Presentation on Precast Infrastructure by Darshit Jhaveri
Head - Technical & Commercial (India), FUJI Silvertech Concrete Pvt. Ltd. Ahmedabad at #33NCCE 33rd National Convention of Civil Engineers at #IEIGSC
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Presentation on Effect of Waste Foundry Sand on Durability Properties of Concrete by Tirth Doshi guided by Dr Urmil Dave & Prof Tejas Joshi at #33NCCE 33rd National Convention of Civil Engineers at #IEIGSC
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Presentation on Flexure Behaviour of Ferrocement Strengthened RC beams by Akshay Dhariwal & Prof Sunil Raiyani, Institute of Technology, Nirma University, Ahmedabad at #33NCCE 33rd National Convention of Civil Engineers at #IEIGSC
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2nd Dr. Jaikrishna Memorial Lecture on Evolution of Bridges by Ashok Basa Past President, The Institution of Engineers (India) delivered during #33NCCE National Convention of Civil Engineers at #IEIGSC
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Presentation on GEO TEXTILES FOR DEVELOPMENT OF NORTH EASTERN REGION by Shri P.S.Barbora, In-Charge, NERC, Ahmedabad Textile Industry’s Research Association (ATIRA) Guwahati done at Workshop on Geo Textiles in Civil Engineering Organized at Ahmedabad by #IEIGSC
Use of GeoTextiles in Civil Engineering : Work on NH 150, ManipurIEI GSC
Presentation done by N Noren Singh, Chief Engineer (Buildings), Manipur during One day workshop on GEO TEXTILES IN CIVIL ENGINEERING organized by #IEIGSC in association of iNDEXTb, L D College of Engineering, Ahmedabad & ATIRA
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Presentation on Comparative Evaluation Of Epoxy Treated Reinforcement And Enamel Treated Reinforcement made by Dr PK Parhi, Professor of Civil Engineering, College of Engineering & Technology, Bhubaneswar at #33NCCE 33rd National Convention of Civil Engineers at #IEIGSC , Ahmedabad
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.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
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Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
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When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
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Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Presentation on Effect of height and number of floors to natural time period of a multi-storeyed building
1. ““EffEct of hEight and numbEr of floorsEffEct of hEight and numbEr of floors
to natural timE pEriod of a multi-storEyto natural timE pEriod of a multi-storEy
buildingbuilding””
PRESENTED BY MENTOR
NILESH V. PRAJAPATI SHRI S.K. PATEL
ASSISTANT ENGINEER SUPERINTENDING ENGINEER
R&B DESIGN CIRCLE, GANDHINAGAR
DATE:21-09-2015
GUIDED BY
SHRI PROF. A.N.DESAI
B.V.M.ENGINEERING COLLEGE,V.V.NAGAR,ANAND
1
2. FLOW OF PRESENTATION
Introduction.
Literature review.
Objective of work and mode of working.
Problem Definition.
Problem formulation.
Software verification.
Results and Discussion.
Conclusion.
Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 2
4. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 4
As per IS 1893:2002 The approximate fundamental natural
period of vibration (T ), in seconds, of a moment-resisting
frame building without brick infill panels may be estimated by
the empirical expression:
Ta = 0.075 h0.75
for RC frame building
= 0.085 h0.75
for steel frame building
Where
h = Height of building, in m.
This excludes the basement storeys, where basement
walls are connected with the ground floor deck or fitted
between the building columns. But it includes the basement
storeys, when they are not so connected.
5. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 5
The approximate fundamental natural period of vibration
( T, ), in seconds, of all other buildings, including moment-
resisting fame buildings with brick infill panels, may be
estimated by the empirical expression:
Ta = 0.09h/√ d
Where
h= Height of building, in m
d=Base dimension of the building at the plinth level, in m,
along the considered direction of the lateral force.
6. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 6
In this work attempt is been made to show that
Natural time period is also a function of Number of
floors and not only of height of building , as it is not
mentioned in above formula .
8. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 8
Literature survey is essential to review the work done in
the area of performance based Engineering.
To take up the specific need to perform the analysis, the
literature like technical papers, journals and books need to
be referred.
The literature review concentrates on a range of
earthquake engineering topics and structural modeling
aspects.
For the understanding of seismic capacity, a review of
literature is required in experimental testing, current
design practice, theoretical strength evaluation and
modeling techniques such as finite element modeling.
9. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 9
The literature review begins with a coverage of general
earthquake engineering topics, which serves to set the
context of the research.
10. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 10
Ms A Cinitha, Dr G M Samuel Knight, Dr V Ramamurthi [P12]
The dynamic relationships between the model and
prototype structure depend on the geometric and
material properties of the structure and on the type of
loading.
Parametric studies have been carried out on
extended numerical model to study the effect of height
of the building, height of storeys, number of storeys
and size of beams and columns and bracings on the
fundamental frequency.
11. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 11
The conclusions drawn as per their work are:
Fundamental frequency against height of the building
behavior showed a non-linear decreasing trend with
increase in height of the building irrespective of the size of
beams and columns.
Increase in height of the building from 10 m to 30 m
decreases the fundamental frequency to one third,
whereas if the cross-section of beams and columns are of
smaller sections, the fundamental frequency decrease by
more than 50% irrespective of the plan of the building.
12. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 12
For a building with constant height, increase in
height of the storeys decrease the fundamental
frequency by more than 20%. the fundamental
frequency of the frames with smaller span increases
by 26% as compared to frames with larger span.
13. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 13
L.Govinda Raju ,G.V. Ramana,C.HanumanthaRao and T.G.Sitharam [P8]
They performed study on Reinforced Cement Concrete
multistory building plane frames for different configurations
of number of bays (each of 4 m span) and storey height (3
m each) were analyzed for their natural frequencies using
Finite Element Analysis package (NISA) without considering
the infill effect.
Figure 1 shows the variation of natural frequencies for
different storey heights and bays corresponding to first and
second modes respectively.
14. Figure 1. Variation of natural frequency with number of bays and storeys in (a) First mode (b) Second mode.
Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 14
15. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 15
Figures 1a and 1b represent the effect of number of
bays and storey height on the natural frequency of the
structure for first and second modes respectively.
It is evident that the magnitude of natural frequencies
is not much influenced by the number of bays.
Further the natural frequency of the structure
decreases as the number of storeys is increased.
It can be noticed from the figures that for 4 to 10
storied buildings, the natural frequency ranges between
1.5 Hz to 3.0 Hz for the first mode and 2.5 Hz to 8 Hz for
the second mode.
16. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 16
D.E. Allen and G. Pernica [P6]
They performed study for Repetitive forces
produced by human activities for the floor acceleration
due to cyclic force and stated that the taller the
columns supporting the floor on which the rhythmic
activity takes place the lower the natural frequency of
the floor.
An example of this occurred when aerobics on the
top storey of a 26-storey building caused second
harmonic resonance due to the axial flexibility of the
columns.
17. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 17
This resonance produced annoying vibrations of
approximately 1% g (gravity) in the offices below.
If the vibration is very large (more than 20% g), and
occurs frequently (e.g., in a health club), then fatigue
failure of the floor can occur.
To prevent collapse due to fatigue or overloading, the
National Building Code (NBC) requires a dynamic
analysis of a floor structure if it has a natural frequency of
less than 6 Hz.
18. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 18
Objective and Mode of working
In this work attempt is been made to show that
Natural time period is also a function of Number of
floors and not only of height of building , as it is not
mentioned in formula as per IS1893:2002.
And also to find out the effect of variation of bays (in
plan) on natural time period, for same height of
building and same storey height.
For This STAAD Pro. Software is used for relevant
analysis
19. The specific objectives were as follows:
•To prepare various R.C.C. models in STADD-Pro .
•To assess the change in natural time period with
respect to variation of height and number of floors of
R.C.C. building.
•To assess the change in natural time period with
respect to variation of number of bays (in plan) for the
same height of R.C.C. building.
Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 19
21. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 21
In this research work STADD-Pro software has been used. In
it, various model of R.C.C. framed building were prepared.
The height of RCC building varies from 60m to 90m with
respect to increase in number of floors from 20 to 30
numbers for the constant storey height of 3 m.
The plan dimension of all models are 70 m × 70 m. All
columns are of same size and also all beams are of same
size in each model.
In each sub sequent model there has been a variation in
number of floors. Suppose in first model, number of floors
are 20. In next model, the number of floors would be 21.
Thus, the variation of each number of floors has been
conducted in each sub-sequent model.
22. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 22
Using STADD-Pro software, ANALYSIS of each model
has been carried out.
Then, concrete design is been carried out manually for
maximum axial load for column and for maximum BM for
beam.
With this actual design the MODAL CALCULATION has
been carried out using STAAD-Pro software.
As the number of floors increases, height of building will be
increased and due to this, variation in natural Time-period
has been obtained.
23. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 23
•For the further analysis, for same height of building
and same storey height, variation in bays (in plan) was
made to find out the effect of number of bays on
natural time period.
•For this variation of bays was made from 11 to 14 in
numbers.
•Hence plan dimension varies from 50m ×50m to
70m× 70m and keeping other dimensions as constant.
24. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 24
Problem formulation:
Plan dimension : 70 m × 70 m
Height of building : 90 m for sample model (varies from 60 m to 90 m)
Height of each storey : 3m (constant)
Number of bays along X-direction: 14 nos.
Number of bays along Y-direction: 14 nos.
Length of each bay(in X-direction): 5m
Length of each bay(in Y-direction): 5m
Number of floors varies as :20,21,22,23,24,25,26,27,28,29,30.
Column size: 450 mm × 300 mm (may be changed as per actual design)
Beam size: 300 mm × 600 mm (may be changed as per actual design)
Modules of elasticity of concrete: 2 × 10^5
Grade of concrete: M-20
Grade of steel: Fe-415
Density of concrete: 25 KN/m3
Density of wall: 20 KN/m3
Live load: 4 KN/m2
Slab thickness: 120 mm
Wall thickness: 230 mm (periphery wall)
115 mm (internal wall)
230 mm (parapet wall)
28. 3D view of a model
Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 28
29. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 29
Load calculation
Various loads were calculated as below:
Slab thickness is 120 mm
Density =25 KN/m3
(for M25)
Floor load:
DL = 0.12×25
=3.00 KN/m2
LL=3.00 KN/m2
Wall load:
For typical floor
Height of storey =3 m
Height of wall =3.0-0.6
=2.4 m
Density =18 KN/m3
Load from external wall =18×.23×2.4
=9.936 KN/m
Load from Internal wall =18×0.115×2.4
=4.968 KN/m
For top floor
Height of parapet wall = 1.00 m
Thickness =0.23 m
Load from parapet wall=18×0.23×1
=4.160 KN/m
30. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 30
As per this revised design, sizes carried out for all
columns as 1000*1000 mm and all the beams as
300*600 mm.
31. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 31
To calculate natural time period for each model,
MODAL MASS CALCULATION has been performed
using Eigen value extraction method in STAAD.pro.,
for the variation of each number of floors and height
for sub-sequent model.
The number of floor varies from 20 to 30 and height
of building varies from 60m to 90m respectively for the
constant storey height of 3m.
For the further analysis the variation in numbers of
bays (in plan) has been made for each building height,
keeping other dimensions (i.e. number of floors and
storey height)as constant and plan dimension varies
as 50m,55m,60m,65m,and 70m keeping storey
height(3m) and total height of building as constant for
that particular model.
32. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 32
For example, If the first model is of 20 storey building and
total height of a building is 60 m and the number of bays
varies as from 10 to 14 each of 5m. hence plan dimension
varies as 50m,55m,60m,65m, and 70m keeping storey
height(3m) and total height of building as constant(60m) for
that particular model.
For these models also the MODAL CALCULATION has
been carried out using Eigen value extraction method using
STAAD-Pro software to calculate natural time period of a
building.
34. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 34
To verify the software, mass and stiffness has been
manually calculated.
After calculating mass and stiffness natural time
period and natural frequency has been calculated for
a single model and natural time period has been
calculated.
35. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 35
Sample calculations to calculate natural time period using Eigen value constant.
Slab = 0.12×25×70×70 = 14700 KN
Beam = 0.3×0.6×25×70×70= 9450 KN
Live load = 70×70×1.5 =7350 KN
Column = 1×1×25×225×3 =16875 KN
Ex. Wall= 0.23×20×70×4×2.4 = 3091.2 KN
Int. Wall=0.115×20×70×26×2.4 = 10046.4 KN
Total mass (m) = 61512.6 KN
= 6151260 kg
E=2×105
N/mm2
I=B×D3
/12
=8.33× 1010
N/mm
K = ∑ ωn
=
= 2.0889×1012
N/m
= 589.067Hz
h= height of column
ω = = 589.067× 0.077*
= 45.358 Hz
T =
= 0.234 Sec
= 0.13845 Sec
Indicates the Eigen-value constant (for20storey) which is calculated from iteration method for different lumped mass systems.
36. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 36
Sr. No
No of
floors
Storey height
(m)
Height of
building
Mass (kg)
Stiffness, *1012
(N/m)
Natural frequency
ωn (Hz)
Constant Frequency ω (Hz)
Natural time period
T (sec)
1 20 3 60 6019884 2.0889 589.067 0.077 45.358 0.13845
Table 1 Results for natural time period for different models using the Eigen
value constant.
42. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 42
Keeping constant Building Height i.e. 90 m, and same plan dimension now variation
is made for the Numbers of floors for the same building and with same member
properties, following results for the natural time period were obtained from Eagan
value factor method as shown in table no 5 and table no 6.
44. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 44
DISCUSSION :
From the results obtained for natural time period using STAAD.Pro. and
formula given in IS1893:2002 it can be stated that values obtained from
STAAD.Pro. using Eigen value extraction method are different than the
values obtained from formula given in code, in which natural time period
is only function of total height of the building and plan dimension of a
building. And as the number of floor increases, Natural time period
also increases.
From this, it can be stated that natural time period is also changes with
variation in number of floors.
45. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 45
From above Results of research work it can be seen that
natural time period is also a function of number of floors and
not only of height of building.
To calculate natural time period mathematical formula can be
revised using rigorous analysis.
CONCLUSION :
46. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 46
Future Scope of work:
This work is based on regular building where plan dimension of a
building in both the direction has been kept symmetrical. Further
work in this area can be achieved by considering irregular
building.
In this work column size has been kept constant throughout the
building height. One may go for the variation of sizes for the
different levels as per the actual design consideration.
In this research work there is no shear wall considered. One may
go for the with shear wall consideration.
47. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 47
References:
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48. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 48
Technical Journals:
1)Earthquake tips,IITK,KANPUR,INDIA,2002
IS Codes:
1)IS 1893:2002 Part-I Indian standard Criteria for earthquake resistant design of structures.
2)IS 13920:1993 Indian standard code of practice for Ductile detailing of reinforced concrete
structures subjected to seismic forces.
3)IS 456:2000 Indian standard code of practice for Plain and Reinforced concrete.
49. Nilesh prajapati-A.E. R& B Design Circle,Gandhinagar. 49
Gratitude to :
Shri Vivek. P. Kapadiya sir, Chief Engineer and MD,GWSRDC,Gandhinagar for
this motivation for this presentation and valuable guidance.
Shri S.K.Patel sir, Superintending engineer, R&B design circle, Gandhinagar for
his valuable support and guidance.
Shri Sunil.B.Prajapati my elder cousin brother and Superintending
engineer, C.D.O, irrigation dept., Gandhinagar for his valuable guidance
throughout my Career.