Seismic Analysis

TERZAGHI’S BEARING CAPACITY THEORY DERIVATION OF EQUATION TERZAGHI’S BEARING CAPACITY THEORY TERZAGHI’S BEARING CAPACITY FACTORS Download vedio link https://youtu.be/imy61hU0_yo

This document discusses seismic analysis of regular and irregular reinforced concrete framed buildings. It analyzes 4 building models - a regular 4-story building, a stiffness irregular building with a soft ground story, and two vertically irregular buildings with setbacks on the 3rd floor and 2nd/3rd floors. Static analysis was performed to compare bending moments, shear forces, story drifts, and joint displacements. Results showed irregular buildings experienced higher seismic demands. The regular building performed best, with the single setback building also performing well. Irregular configurations increase seismic effects and should be minimized in design.

This document provides definitions and explanations of key concepts in reinforced concrete design. It defines reinforced concrete as a composite material made of concrete and steel reinforcement. The purpose of reinforcement is to improve the tensile strength of concrete. The Limit State Method of design considers both the strength limit state and serviceability limit state, making it a more realistic and economical approach compared to other methods like Working Stress Method and Ultimate Load Method. Key factors of safety in the Limit State Method include partial factors for concrete γc = 1.5, and for steel γs = 1.15.

This document provides an overview of a project report on designing a multi-storied reinforced concrete building using ETABS software. The objectives are to analyze, design, and detail the structural components of the building. The methodology involves preparing CAD drawings, calculating loads, analyzing the structure, and designing and detailing structural elements. The building to be designed is a residential building with ground + 5 floors located in Chalikkavattom. Loads like dead, live, wind, and seismic loads will be calculated according to Indian codes and applied in the ETABS analysis model.

This document provides an overview of slope stability and analysis. It defines different types of slopes as natural, man-made, infinite and finite. Common causes of slope failure like erosion, seepage, drawdown, rainfall, earthquakes and external loading are described. Key terms used in slope stability are defined, including slip zone, slip plane, sliding mass and slope angle. Types of slope failures are identified as face/slope failure, toe failure and base failure. Methods for analyzing finite slope stability, like Swedish circle method, Bishop's simplified method and Taylor's stability number are introduced. Infinite slope analysis is described for cohesionless, cohesive and cohesive-frictional soils. Example tutorial problems on slope stability calculations are

Structural Analysis And Design is a structural analysis and design software. It includes tools for 3D modeling, analysis, and design of structures according to various international codes. The software was originally developed by Research Engineers International and later acquired by Bentley Systems. It allows engineers to generate models using different elements like frames, plates, and solids. Various types of structures like trusses, planes, and spaces can be modeled and analyzed. The software provides tools for assigning properties, loads, boundary conditions, and performing analysis to calculate member forces and deflections. The results can then be used for structural design of elements like beams, columns, slabs, and foundations.

This document discusses reinforced concrete columns. It begins by defining columns and different column types, including based on shape, reinforcement, loading conditions, and slenderness ratio. Short columns fail due to material strength while slender columns are at risk of buckling. The document covers column design considerations like unsupported length and effective length. It provides examples of single storey building column design and discusses minimum longitudinal reinforcement requirements in columns.

This document discusses response spectra and design spectra. It begins by explaining how response spectra are developed by analyzing the response of single-degree-of-freedom systems to ground motion records and plotting the maximum response versus natural period. Design spectra are then developed as smooth versions of response spectra to account for uncertainties in natural period. The key differences between response and design spectra are also summarized.

Get PPT here https://civilinsider.com/design-philosophies-of-rcc-structure/ www.civilinsider .com www.civilinsider .com www.civilinsider .com www.civilinsider .com Various design philosophies have been invented in the different parts of the world to design RCC structures. In 1900 theory by Coignet and Tedesco was accepted and codified as Working Stress Method. The Working Stress Method was in use for several years until the revision of IS 456 in 2000. What are the Various Design Philosophies? Working Stress Method limit state method ultimate load method #civil insider

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,

This document discusses counterfort retaining walls. It defines a retaining wall and lists common types, focusing on counterfort retaining walls. It describes the components and mechanics of counterfort walls, noting they are more economical than cantilever walls for heights over 6 meters. The document also covers forces acting on retaining walls, methods for calculating active and passive earth pressures, and stability conditions walls must satisfy including factors of safety against overturning and sliding and limiting maximum pressure at the base.

This document summarizes the procedures for conducting a pile load test to determine the load carrying capacity of a pile. The test involves installing a test pile between two anchor piles and applying incremental loads through a hydraulic jack while monitoring settlement. Loads are applied until the pile reaches twice its safe load or a specified settlement. A load-settlement curve is plotted to determine the ultimate load and safe load based on settlement criteria. The test provides values for maximum load, permissible working load, and pile settlement under different loads.

This document provides an analysis and design of a G+3 residential building. It includes details of the building such as dimensions, material properties, and load calculations. An equivalent static analysis is performed to calculate the seismic lateral loads at each floor level. The results of the structural analysis including bending moment and shear force diagrams are presented. Slab, beam, column and footing designs are to be covered in the thesis work according to the scope.

This document provides an overview of the design of compression members (columns) in reinforced concrete structures. It discusses various types of columns based on reinforcement, loading conditions, and slenderness ratio. It describes the classification of columns as short or slender. The document also covers effective length, braced vs unbraced columns, codal provisions for reinforcement, and functions of longitudinal and transverse reinforcement. Key points include types of column reinforcement, minimum reinforcement requirements, cover requirements, and assumptions for the limit state of collapse under compression.

This document provides design aids for reinforced concrete structures based on Indian Standard IS: 456-1978 Code of Practice for Plain and Reinforced Concrete. The design aids cover material strength and stress-strain relationships, flexural members, compression members, shear and torsion, development length and anchorage, working stress design, deflection calculation, and general tables. Charts and tables are provided for preliminary and final design of beams, slabs, and columns. Assumptions made in developing the design aids are explained. An example illustrates the use of the design aids. Important points regarding the use and limitations of the charts and tables are noted. The design aids were prepared based on examination of international handbooks and consultation with Indian

The document discusses the design of footings for structures. It begins by explaining that footings are needed to transfer structural loads from members made of materials like steel and concrete to the underlying soil. It then describes different types of shallow and deep foundations, including spread, strap, combined, and raft footings. The document provides details on designing isolated and combined footings to resist vertical loads and moments based on provisions in IS 456. It also discusses wall footings and combined footings that support multiple columns. In summary, the document covers the purpose of footings, various footing types, and design of isolated and combined footings.

Approximate analysis methods make simplifying assumptions to determine preliminary member forces and dimensions for indeterminate structures. Case 1 assumes diagonals cannot carry compression and shares shear between diagonals. Case 2 allows compression in diagonals. Portal and cantilever methods analyze frames by dividing into substructures at assumed hinge locations, solving each sequentially from top to bottom.

This document discusses different methods for seismic analysis of reinforced concrete buildings, including linear static, nonlinear static, linear dynamic, and nonlinear dynamic analysis. It provides details on each analysis method, including the steps involved. It also presents a case study that compares the results of static and dynamic analysis methods on regular and irregular multi-storey buildings, finding that dynamic analysis more accurately predicts structural response.

This document discusses different methods for seismic analysis of reinforced concrete buildings, including linear static, nonlinear static, linear dynamic, and nonlinear dynamic analysis. It provides details on each analysis method and outlines the general procedures. It also presents a case study that compares the results of equivalent static, response spectrum, and time history analysis of regular and irregular multi-storey buildings to determine storey displacements and seismic behavior.

This document discusses seismic strengthening of multi-storey buildings with soft storeys. It defines local and global damage indices, with interstorey drift ratio (IDR) identified as an easy way to find the damage index. Analytical approaches like pushover analysis and time history analysis are evaluated. Experimental problems analyze buildings with varying soft storey heights subjected to earthquakes, comparing damage indices among storeys. The conclusion is that damage index increases with more storeys and higher soft storeys, and can exceed 1 based on IDR. Pushover analysis provides capacity while time history gives maximum IDR under seismic loads.

This document summarizes a presentation on analyzing the seismic behavior of multi-story buildings with varying heights using ETABS software. It analyzes buildings with 5, 6, 7, and 8 stories under seismic, dead, and live loads. The objectives are to check the seismic response of buildings using ETABS, analyze forces, moments, stresses, strains, and deformations, and analyze story drift, displacement, shear, stiffness, period, and frequency on different floors. The methodology involves modeling the buildings in ETABS and subjecting them to static and dynamic analysis to determine responses like base shear, maximum displacement, tensile forces, and moments and shear forces.

EVALUATION OF SEISMIC FORCES AS PER IS 1893_2016

This document discusses different methods for analyzing reinforced concrete buildings under seismic loads, including linear static, nonlinear static, linear dynamic, and nonlinear dynamic analysis. Linear static analysis (equivalent static analysis) distributes seismic forces along the height of the building based on its mass and fundamental period, while nonlinear static (pushover) analysis applies monotonically increasing lateral loads until a target displacement is reached. Linear dynamic analysis uses modal response spectrum analysis to determine seismic forces based on the building's vibration modes and acceleration response spectrum. Nonlinear dynamic analysis uses time-history analysis to model the structure's exact nonlinear response over time under recorded earthquake ground motions.

This study presents the procedure for seismic performance estimation of high-rise buildings based on a concept of the capacity spectrum method. In 3D analytical model of thirty storied buildings have been generated for symmetric buildings Models and analyzed using structural analysis tool ETABS. The analytical model of the building includes all important components that influence the mass, strength, stiffness and deformability of the structure. To study the effect of concrete core wall & shear wall at different positions during earthquake, seismic analysis using both linear static, linear dynamic and non-linear static procedure has been performed. The deflections at each storey level has been compared by performing Equivalent static, response spectrum method as well as pushover method has also been performed to determine capacity, demand and performance level of the considered building models. From the below studies it has been observed that non-linear pushover analysis provide good estimate of global as well as local inelastic deformation demands and also reveals design weakness that may remain hidden in an elastic analysis and also the performance level of the structure. Storey drifts are found within the limit as specified by code (IS: 1893-2002) in Equivalent static, linear dynamic & non-linear static analysis.

This document provides an overview of earthquake resistant design of structures. It discusses key topics like seismology, seismic zonation maps, and various methods of earthquake analysis for structural design purposes. These include equivalent static analysis, nonlinear static (pushover) analysis, response spectrum dynamic analysis, and time history dynamic analysis. Load combinations for accounting for multi-directional ground shaking are also addressed. The document serves as a reference for understanding earthquake effects on structures and performing appropriate seismic analyses.

This document summarizes an investigation into the performance of flat plate reinforced concrete buildings under nonlinear pushover analysis. The study evaluates bare frame structures with different percentages of masonry infill, as well as structures with soft stories or shear walls. Pushover analysis was performed on a 7-story model building to determine base shear, displacement, story drift, and hinge formation at different performance levels. Results show that infill and shear walls improve seismic performance by reducing displacement, and that placing soft stories higher in the structure increases strength and stability. Shear walls performed best and controlled hinge formation, indicating more uniform response.

A soft storey is one which has less resistance to earthquake forces than the other storeys; Buildings containing soft stories are extremely vulnerable to earthquake collapses, since one floor is flexible compared to others. Vulnerability of buildings is important in causing risk to life hence special consideration is necessary for such soft storey RC buildings. In the present study, analytical investigation of a RC building by considering the effect of soft storey situated in seismic Zone-V of India, in accordance with IS 1893-2002 (part-1), is taken as an example and the various analytical approaches (linear static and nonlinear static analysis) are performed on the building to identify the seismic demand and also pushover analysis is performed to determine the performance levels, and Capacity spectrum of the considered, also Storey Shear is compared for 3 models by using Finite Element Software Package ETAB’s 9.7.4 version.

Abstract Structure are highly susceptible to serve damages in earthquake scenario, so choosing an appropriate lateral force resisting bracing systems will have a significant effect on performance of the structure. So this present study is aimed at evaluating and comparing various types of eccentric steel bracings for 12 storey RC frame building resisting on sloping ground configurations. For this 5 types of bracing systems like X-Bracing, Diagonal bracing, K- bracing, V-bracing and inverted V bracing are considered on the outer periphery of the buildings with step back and set back – step back type configurations are modeled and analyzed. The models are compared for different aspects within the structure, such as the maximum storey displacement, base shear, storey drift and storey shear, the structure is analyzed for seismic zone V and medium soil condition as per IS 1893:2002 using ETABS software. Results conclude that on sloping ground due to irregularity on ground surface, the structures are more vulnerable to earthquakes. Hence use of eccentric steel bracing is an effective and economical way to resist earthquake forces, Inverted V type bracing performs well compared to other bracing types. By using inverted V type bracing in step back buildings types maximum storey displacement of 70% and storey drift of 66% are obtained. Similarly for setback – step back configuration maximum storey displacement of 74% and storey drift of 70% are obtained respectively. Keywords: X-Bracing, Diagonal Bracing, K- Bracing, V-Bracing and Inverted V Bracing

This document discusses earthquake analysis and earthquake resistant design concepts. It begins with terminology related to earthquakes and seismic analysis. It then discusses the basic concepts of earthquake resistant design including structural simplicity, uniformity and symmetry. It also covers equivalent static analysis and calculating the seismic design base shear. The document discusses seismic zone coefficients, structural importance factors, response reduction factors, and seismic design categories. It concludes with discussions of site classification, soil factors, time periods, and determining lateral force coefficients and building masses.

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.

Reinforced concrete frame buildings are most common type of construction in urban India, which is subjected to several types of forces during their life time such as static forces and dynamic forces due to wind and earthquakes. The static loads are constant with time, while dynamic loads are time varying, causing considerable inertia effects .It depends mainly on location of building, importance of its use and size of the building. Its consideration in analysis makes the solution more complicated and time consuming and its negligence may sometimes becomes the cause of disaster during earthquake. So it is growing interest in the process of designing civil engineering structures capable to withstand dynamic loads . The behavior of building under dynamic forces depends upon its mass and stiffness properties, whereas the static behavior is solely dependent upon the stiffness characteristics.

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.

Pushover is a static-nonlinear analysis method where a structure is subjected to gravity loading and a monotonic displacement-controlled lateral load pattern which continuously increases through elastic and inelastic behavior until an ultimate condition is reached. Lateral load may represent the range of base shear induced by earthquake loading, and its configuration may be proportional to the distribution of mass along building height, mode shapes, or another practical means. The static pushover analysis is becoming a popular tool for seismic performance evaluation of existing and new structures. The expectation is that the pushover analysis will provide adequate information on seismic demands imposed by the design ground motion on the structural system and its components. The purpose of the paper is to summarize the basic concepts on which the pushover analysis can be based, assess the accuracy of pushover predictions, identify conditions under which the pushover will provide adequate information and, perhaps more importantly, identify cases in which the pushover predictions will be inadequate or even misleading.

This document discusses the non-linear static (pushover) analysis of irregular building systems. It presents 6 building models of 13-story reinforced concrete buildings with different configurations of masonry infill walls and concrete shear walls to study their seismic performance. Non-linear static pushover analysis is performed using ETABS software to obtain the capacity curves and evaluate the performance of each model under seismic loading. The results show that the inclusion of masonry infill walls and concrete shear walls affects the seismic response of the irregular buildings, and that some configurations perform better than others.

A large numbers of existing buildings in India are severely deficient against earthquake forces and the number of such buildings is growing very rapidly. This paper presents a way of using energy dissipation devices for seismic strengthening of a RC framed structure. The objective was to improve the seismic performance of the building to resist the earthquake. The viscous dampers are used as an energy dissipation device in the form of single, double, inverted V, V type of dampers with different percentages of damping such as 10%, 20% and 30% to prevent building from collapse in a major earthquake and also to control the damage during earthquake. The performance of the buildings is assessed as per the procedure prescribed in ATC-40 and FEMA 356.

This document summarizes a study that evaluated the seismic behavior of low-rise reinforced concrete buildings in Venezuela. Three models of a sample building were analyzed: the original building design, a resizing design, and a displacement-based design. Nonlinear static and dynamic analyses were performed using software. Results found the original design did not meet code drift limits and had lower ductility than the other designs. The study aims to improve seismic design procedures in Venezuela.

1. This document discusses performing a pushover analysis on a flat slab building using SAP2000 software to evaluate its seismic performance. 2. A pushover analysis applies increasing lateral loads to identify weak zones and determine the building's strength and deformation capacities. 3. The analysis revealed that retrofitting weak columns with jacketing and adding beams could significantly improve the building's lateral strength and stiffness to withstand seismic forces.

This document provides details of the structural analysis and design of a commercial and residential building using STAAD.Pro, AutoCAD, and STAAD.Foundation software. The building is located in Trivandrum, Kerala and consists of a basement, ground plus three floors. The document describes the site details, building plans, load calculations, modeling in STAAD.Pro, design of structural elements like beams, columns, foundation, and reinforcement details. Pile foundation is adopted based on the bore log details. The analysis helps gain knowledge of designing various components using structural analysis and design software.

This document discusses scheduling problems in complex, poorly structured projects. It notes that scheduling becomes difficult when costs and durations depend on other activities or resources are specialized. A practical approach is to have experienced managers review and modify schedules before implementation. For more complex projects, the best solution is an iterative "generate and test" process where schedules are generated, tested for feasibility and constraints, and improvements are identified to generate new alternatives to test. The number of possible schedules is enormous, so considerable insight is needed to generate reasonable alternatives efficiently. Interactive scheduling systems using graphical displays and easy modification of schedules can help evaluate alternatives rapidly.

Sulphate attack occurs when sulphates react with hardened cement paste, causing expansion and cracking of concrete. Soil sulphates do not severely damage concrete, but water sulphates can enter porous concrete and react with hydration products. This forms ettringite which increases in volume, disintegrating the concrete. Sulphate attack can be external from sulphates in groundwater penetrating concrete, or internal from sulphates in the original mix. Delayed ettringite formation is a type of internal sulphate attack where ettringite decomposes during curing then reforms, expanding and damaging the concrete.

This document discusses various types of earth moving equipment used in construction projects. It describes excavation equipment like power shovels, backhoes, draglines, and clamshell buckets used to excavate earth and load trucks. It also covers excavating and earth moving equipment like scrapers and bulldozers used to dig and transport materials over long distances. Finally, it summarizes earth compacting equipment like smooth drum rollers, sheepfoot rollers, and pneumatic tyred rollers used to compact excavated earth in embankments and prepare surfaces for construction.

Dampers are mechanical systems that dissipate earthquake energy by deforming or yielding. They absorb seismic energy, reducing forces on structures and controlling building oscillations. Common types include hydraulic dampers using fluid flow, electro-rheological fluid dampers using variable viscosity fluids, metallic dampers using hysteretic behavior of metals, steel dampers using frame deformation, and friction dampers using clamped friction surfaces. Shape memory alloys also dissipate energy through large strain recovery without damage. Dampers direct earthquake energy to dissipating devices within structures, transforming mechanical energy into heat.