Seismic analysis and design of a multistorey building. Such variation in storey stiffness could trigger soft storey. Here, we are going to briefly present some practical analysis and design of some reinforced concrete elements using staad pro software, orion software and manual calculations. Staad pro software can be used for analyzing and designing of the preengineered buildings. These results will also be compared with manual calculations of a sample beam and column of the same structure designed as per is 456. A soft story building is a multi story building in which one or more floors have windows, wide doors, large unobstructed commercial spaces, or other openings in places where a shear wall would normally be required for stability as a matter of earthquake engineering design. A comparative study of different configuration of shear. These are basically ground story which consists of only columns without any pattern wall. Preengineered building peb concept is a new conception of single storey industrial building construction. However, the price of this force reduction is paid in the form of. The objective of this paper is to analysis design rc building located in the most active seismic zone region in saudi arabia to mitigate seismic loads. A study on the effectiveness of bracing systems in soft storey steel.
Mar 02, 2017 rigid diaphragm, drift, vertical irregularities in staad john paul dela rosa. The building having soft storey at any floor is vulnerable for damage during earthquake due to lack of stiffness of soft storey. Civil engineers are using this software to perform 3d analysis and design for any kind of low and high rise structure. Here in this project work based on software named staad pro has been used. Structural software for building analysis and design etabs. Weak storey could occur where the walls at upper floors are omitted at a lower first or ground floor to create open plan space for retail or communal places. K, arpan herbert international journal of civil and structural engineering volume 2 issue 3 2012 872 table 4. In the industry we use staad to model and analyse the building, and then design the individual structural members in excel.
Pro will perform this check when the option check soft story command is used following a floor diaphragm. For structural engineer, now a days for designing buildings of 80 storey or even 110 storeys, manual calculations are becoming completed for analysis purpose. Which software should i learn as a structural engineer. This methodology is versatile not only due to its quality predesigning and prefabrication, but also due to its. Structural engineering, analysis, and design software. Pro is a professional choice for structural engineering in a variety of metal, concrete, wood, aluminum, and cold steel structures for the design of almost any type of instrument, such as a plug. Structural enterprise the most popular structural applications in a single a costeffective license. A five storey building with a open ground storey is analysed with and without braced type viscous dampers placed at soft storey. Storey it is the space between two adjacent floors.
The process of designing is defined in the best suitable manner it can be. Analysis by staadpro and design of structural elements by. Story drifts from staad with dynamic analysis structural. Pro software package is a structural analysis and design software which helps in modeling. Storey stiffness seismic design structural engineering. Pro is software for structural analysis and design from research engineers international staad. Pro advanced adds faster, more advanced and complex analysis. All the specific results are also shown in the end. In essence, a soft story has inadequate shear resistance or inadequate ductility energy absorption capacity to resist the earthquakeinduced building stresses.
Staad pro software is used for designing structures, for four earthquake zones. Check soft story command checks for plan and vertical irregularities in a building viz. Story drifts from staad with dynamic analysis mike20793 structural 24 mar 16 20. But, on analysis staad shows the warnings as floor levels are not defined. Staad pro is a much known structural analysis and design software across the world. And especially in some country staad pro is used to perform steel structure analysis and design. Mar 11, 2018 primary loads to be considered would be. The building without soft storey is found to be safer during strong ground motions as compared to building having soft storey at any floor. In late 2005, research engineers international was bought by bentley systems staad. For the analysis of building staad pro v8i is used. In this study the variation in the structure was done while designing, considering omrf and smrf structures. Soft storey it is one in which the lateral stiffness is less than 70 percent of that in the storey above or less than 80 percent of the average lateral stiffness of the three storeys above. Introduction soft story is an open storey, which is not that much capable to resist lateral forces as compared to above non soft storey floors.
What are loads to be considered in the design of a. Analysis of soft storey building in different seismic zones. Staad pro software manuals collection includes staad pro technical manual, staad pro v8i for beginners, staad. It is one of the effective software which is used for the purpose of analysis and design of structure by the structural engineers. Study of base shear and storey drift by dynamic analysis. Nonlinear time history analysis is carried out using sap2000 software and comparisons are shown in a tabular and graphical format.
As per the story stiffness printed out by the software, i see that the stiffness of the story at 22 ft is less than 60% of the stiffness of the story above and less than 70% of the average stiffness of 3 stories above. Mar 01, 2015 staad pro software manuals collection includes staad pro technical manual, staad pro v8i for beginners, staad. Analysis of building with soft storey during earthquake. Pro output by including the command print story stiffness in the post analysis print commands section. Introduction soft story or stilt storey is a feature which can be seen frequently in india and abroad also, generally used for parking or retail purpose. Additionally, the story stiffnesses used in calculating story drift or checking soft stories can be added to staad. From the design results of beams, it may conclude that etabs gave lesser area of required steel as compared to staad pro. Response spectrum analysis as per is1983 in staad pro. Soft story the story which the latteral stiffness is less than 70% of the stiffness of the story above. Percentage change in storey shear for the different buildings is also evaluated. Unless you are using a nonlinear analysis, the drifts youre getting are elastic, so you increase them based on the. In late 2005, research engineers international was bought by bentley systems.
I have to look into it further and will revert back. Pro, all suggested and ranked by the alternativeto user community. Abstract soft first storey is a typical feature in the modern multi storey constructions in. Pro to design steel structural elements for qatars luxury alfardan office tower. Spring mass model with the lateral forces are also plotted for the different buildings. Design results of a sample beam and column section total reinforcement sq. The seismic response of soft storey on highrise buildings and the effect of the seismic loads on the member forces of the basement are investigated in this study. The bentley staad or staad pro software is the first and the best 3d engineering design and design software for the world, and is the end point of any builder software purchase. Our builtin antivirus scanned this download and rated it as 100% safe. Response spectrum specification as per the indian is. When used, the program will exclude the effect of any other forms of lateral force resisting structural. Example seismic analysis and design of a six storey building problem statement.
Design of multistoried residential building using staad. Structural engineering, analysis, and design software staad. This pc program was developed to work on windows xp, windows vista, windows 7, windows 8 or windows 10 and can function on 32bit systems. Soft storey is one in which lateral stiffness is less than. Initially we started with the analysis of simple 2 dimensional frames and manually checked the accuracy of the software with our results. Soft story checking is only valid for structures having vertical elements in the form of columns and shear wall without opening.
The structure analysis and design is done using staad. The warning shown for soft story with respect to floor levels not being defined is because individual floor heights should be defined before using the define command or any primary response spectrum load. The finite element analysis program rfem is a powerful software for quick and easy modeling, structural analysis and design of 2d and 3d models consisting of member, plate, wall, folded plate, shell, solid, and contact elements. They are two different software but their applications are quite similar. How to design multistoried steel structure in staad pro. It gives the bending moment, axial steel structure so that the design can be done using tapered sections and check for the safety. Pro is the structural engineering professionals choice for steel, concrete, timber, aluminum, and coldformed steel design of virtually any structure including culverts, petrochemical plants, tunnels, bridges, piles, and much more through its flexible modeling environment, advanced features, and fluent data. The last time i had worked with staad pro, their designing module was a bit limited and could not give detailed results. This forum also aims in aiding professionals from allied fields such as architecture, construction, sociology, planning, conservation and disaster mitigation to interact with. Seismic analysis of open soft storey building for different. Lateral force developed on building and shear induced on the base of building during earthquake depends on mass and stiffness of structure, irregularity introduced due to soft first storey causes damages on columns when the ground shakes. A soft storey, also known as a weak story, is defined as a story in a building that has substantially less resistance, or stiffness, than the stories above or below it. Pro output by including the command print story stiffness in the post.
Comparison of design results of a structure designed using staad and etabs software prashanth. First, is the reduction in spectral acceleration and base shear due to increase of natural period of vibration of structure as in a base isolated structure. Staad pro is a renowned structural analysis and design software that is used all over the world, and this post is aimed at investigating the analysis of beam and raft foundation using staad pro v8i. V8i and a cross check is done for selected members using limit state method of design as per is 4562000 uses a. A typical soft story building is an apartment building of three or more stories located over a ground level with large. The building is located in seismic zone iii on a site with medium soil. Larger storey drift occurs on first floor soft storey than the upper storeys which are stiffer7. An investigation on the analysis of beam and raft slab. Modern codes of practice are increasingly recognising the computational power of structural analysis softwares. Numbers of beams and columns in each type are given in table 1. Feb 25, 2014 soft storey it is one in which the lateral stiffness is less than 70 percent of that in the storey above or less than 80 percent of the average lateral stiffness of the three storeys above. Pdf seismic response analysis of tall building using staad. Staad pro stands for structural analysis and design.
Once you learn the principles of how to build a meaningful accurate results structural model in any program, the question of switching and of which specific softwa. Staad pro v8i software is widely used in analyzing and designing structures buildings, bridges, towers, transportation, industrial and utility structures. Pro, all suggested and ranked by the alternativeto. Inelastic seismic analysis of reinforced concrete frame. The design involves load calculations manually and analyzing the whole structure by staad pro. Planning is done using 3d modeling software the 2011 revitwith the help of auto cad 2014. Weak story the story which the story strength is less than 80% of that the story above.
Static analysis in the present work, using the staad pro software. Pro is used to generate a model of a truss, which can be analyzed using the same software. Seismic response of soft storey on high rise building frame. These typical problems have been solved using basic concept of. The soft storey concept has technical and functional advantages over the conventional construction. Comparison of design results of a structure designed using. Incorporating 40 years of continuous research and development, this latest etabs offers unmatched 3d object based modeling and visualization tools, blazingly fast linear and nonlinear analytical power, sophisticated and comprehensive design capabilities for a widerange of materials, and insightful graphic. A soft story building is a multistory building in which one or more floors have windows, wide doors, large unobstructed commercial spaces, or other openings in places where a shear wall would normally be required for stability as a matter of earthquake engineering design. Arab engineering bureau saved nearly 30 percent in resource hours and lowered project costs using staad. Analysis of soft storey building in different seismic. Shear force, lateral displacement and support reactions, with the help of staad. How to design a multistorey building in staad pro quora. Staad pro software manuals civil engineering community. Analysis of building with soft storey during earthquake irjet.
Static eccentricity ea it is the distance between centre of mass and centre of rigidity of floor 1. The design methods used in staad pro analysis are limit state design conforming to indian standard code of practice. A multi storey reinforced concrete building, in haql city, was seismically analyzed and designed using the equivalent lateral force procedure with the aid of sap200 software. Soft storeys have been considered by same floor heights and effect of infill walls is ignored.
A six storey building for a commercial complex has plan dimensions as shown in figure 1. Pdf seismic response of soft storey on high rise building frame. Evaluation of the storey stiffness due to soft storey of multi storied building considering various models will be presented in final phase of project. Perform comprehensive analysis and design for any size or type of structure faster than ever before using the new staad. A typical soft story building is an apartment building of three or more. Ultimately, we are going to make some comparisons of the results obtained based on the different methods adopted in. Pro structural analysis and design free book download staad. Computer aided analysis and design of multistoreyed buildings. Etabs 2015 torsional irregularity check with seismic loads.
Due to the modular software concept, you can connect the main program rfem with the corresponding add. Confidently design any type of structure and share your synchronized model data among your design team, in one integrated set of applications. It can be observed that as the height and area of building increases the base shear and storey drift increases. Structural engineering forum of india, sefi is a forum that enables and supports interaction among structural engineers and addresses the issues that concern them. Our project is aimed to complete with the help of staad pro gives more precise and accurate results than manual techniques. Pabitra ranjan maiti associate professor department of civil engineering iitbhu, varanasi duration of project work. Complete your steel, concrete, timber, aluminum, and coldformed steel projects, on time and in. Pro is one of the most widely used structural analysis and design software products worldwide. In such, ground storey possesses lower storey stiffness to that of the upper storeys thereby rendering it to a soft storey. A soft storey or a weak storey is one in which the lateral stiffness is less than. Pro for windows, mac, linux, web, software as a service saas and more. Seismic analysis of multi storey reinforced concrete. Analysis of soft storey building in different seismic zones by staad.
Seismic analysis of open soft storey building for different models. Faculty of technology, structural engineering department. Threedimensional structural software for the analysis and design of building systems. Rigid diaphragm, drift, vertical irregularities in staad. The check soft story option may added to a floor diaphragm command set to check for soft stories per either is1893. These weaknesses are usually created by sharp changes in stiffness, strength andor ductility, and the effects of these weaknesses are accentuated by poor distribution of reactive masses. How to check story drift in staad pro lesson duration. Bentleys staad pro v8i is a structural designing software used around the globe for this purpose. Two storey reinforced concrete design per nscp 2015 staad part 5 of 8 duration. Confidently design steel, concrete, timber, aluminum, and coldformed steel structures anywhere in the world using over 90 included international design codes.
Most of the existing commercial complexes have this feature in common. Soft story collapse building research institute p ltd. Development of multistoried rcc building model with soft. The above irregularity is one of the main reasons of high rise building damages of earthquake. This report includes the concrete design of beams and columns of a two storey building. I have specified the check soft storey command in my model in order to tel the program to do the soft storey checks. Few standard problems also have been solved to show how staad pro can be used in different cases. In shaking a building, an earthquake ground motion will search for every structural weakness. For more detail, please see in ubc code table 16l oap.