Analytical Investigation of Structural Behaviour of Conventional Slab and Flat Slab in Multi-storeyed RCC Framed Structure

Abstract

Analysis and design of buildings must take earthquakes into account. Analyzing how a structure will react to a givenset of loads is called structural analysis. Design is the process of determining the structure\'s proper parameters. It would take a long time to do structural analysis and design by hand. Any building may be easily analysed and designed with the help of software. The goal of this research and design study is to compare and contrast four common commercial building slab configurations—the conventional slab, the flat slab with drop panels, the grid/waffle slab, and the structure with a load bearing wall. At get to the results, a study was run in STAAD to analyse the impact of varying pressures on two different slab designs.The cutting edge of computer programming. The IS-1893:2002 standard mandates the incorporation of seismic forces. We used IS-456:2000 to determine how wide, tall, and deep to make the beams, columns, and slabs. IS-875:1987 (Parts 1 and 2) specifies the requirements for applying load combinations, dead loads, and imposed loads (Parts 3 and 5). (Part 5). Wind speeds of 55 metres per second and an earthquake zone of 5 will be employed as criteria in the next research. The results of a research comparing the displacements, moments, shear forces, and axial forces in two different slab pattern structures are shown using bar charts. Data is presented in the form of tables and bar charts. In general, the greater the number of stories, the greater the amount of movement between floors. Buildings using grid slabs performed better in the examination of the building\'s resistance to wind and seismic loads, and they were also shown to be more cost-effective.

Introduction

Urban space limitations have driven the evolution of low-rise, mid-rise, and high-rise buildings. These structures often use conventional reinforced concrete (RC) slabs, flat slabs, and waffle slabs. Engineers typically employ the "Beam-Slab Load Transfer" technique, where slabs are supported by beams and columns. Flat slabs, by contrast, eliminate beams and transfer loads directly to columns.

Key Concepts:

Types of Slabs:

1. Flat Slab:

   • Slab rests directly on columns (no beams).

   • Easier load transfer but may lack strength without column heads or slab drops.

   • Common in open floor designs like offices.

2. Conventional Slab:

   • Slab supported by beams and then by columns.

   • Requires more formwork and material but is structurally strong.

3. Waffle/ Grid Slab:

   • Grid-like slab structure with deep sides.

   • Ideal for auditoriums and malls due to fewer columns and aesthetic appeal.

Multipurpose Buildings and Urbanization:

• Multipurpose high-rises meet growing urban housing and service needs.

• Efficient land use and vertical expansion are essential in cities like Jagathy, Trivandrum, where space is limited and waste accumulation is high.

• A proposed structure includes three basements, five floors, and six penthouses using AutoCAD, STAAD Pro, SketchUp, and manual design tools.

Importance of Seismic and Wind Analysis:

• High-rise buildings must account for earthquake and wind loads.

• Seismic zones greatly influence structural design.

• Poorly designed high-rises may fail under lateral loads.

Literature Review Insights:

1. Green Design (2016): Emphasizes sustainability and minimal material use.

2. Software Comparison (2015-2017): STAAD Pro, ETABS, and SAP offer differing design accuracy and usability.

   • ETABS uses less steel for beams; STAAD Pro offers more precise structural outputs.

3. Slab Configurations:

   • Flat slabs have lower base shear but higher deflection in irregular structures.

   • Grid slabs are more expensive but allow for wider spans and better aesthetics.

4. Sloping Site Challenges:

   • Structures on sloped terrain face higher seismic risks due to varying column heights and soil interaction.

Methodology:

• A C-shaped G+6 structure is proposed with specific dimensions (40m x 48m).

• 384 m² central open space.

• Beam, slab, and column designs follow IS 456:2000 standards.

• Tools used include STAAD Pro for modeling, with design workflows defined for accuracy and efficiency.

Structural Component Details:

• Beams: Resisting loads perpendicular to their length, with detailed shear and bending moment analysis.

• Columns & Slabs: Dimensions provided for various load and span conditions.

• Structural behavior is analyzed under seismic and wind loads, accounting for storey displacement, base shear, and material efficiency.

Conclusion

Axialforceisdetermined bymeasuringtheweight ofthecolumn atitsfooting. When determining column moments, alargenumber of load permutations are considered. Therearenumerous hubs in this column.Takea look at the building from all angles, and see it from a third-person perspective. Each number is shown below. Each of thehighlighted numbers is shown clearlyin both graphs. Multiple load combinations were used to calculate the axial force imparted by the column. Loads include DL+WL+EQX, 1.2(DL+LL+WLX), 1.5(DL+WLX), and 1.5(DL+EQX). You can see from the numbers that there is no need to look at any other load combinations as their moment values are so much less than the ones being looked into.

References

[1] S.M.MetevandV.P.Veiko,LaserAssistedMicrotechnology,2nded.,R.M.Osgood,Jr.,Ed.Berlin,Germany:Springer-Verlag,1998. [2] J.Breckling,Ed.,TheAnalysis of DirectionalTimeSeries:Applications toWindSpeedandDirection,ser.Lecture NotesinStatistics.Berlin,Germany:Springer, 1989, vol. 61. [3] S. Zhang, C. Zhu, J. K. O. Sin, andP. K. T. Mok, “A novel ultrathin elevatedchannel low-temperature poly-Si TFT,” IEEE ElectronDeviceLett., vol. 20, pp.569–571, Nov. 1999. [4] M. Wegmuller,J. P. vonder Weid, P. Oberson, andN.Gisin,“Highresolution fiber distributedmeasurements withcoherent OFDR,” inProc. ECOC’00,2000,paper 11.3.4, p. 109. [5] R.E.Sorace,V.S.Reinhardt,andS.A. Vaughn,“High-speeddigital-to-RFconverter,”U.S.Patent5668842,Sept.16,1997. [6] (2002)TheIEEEwebsite.[Online].Available:http://www.ieee.org/ [7] M.Shell.(2002)IEEEtranhomepageonCTAN.[Online].Available:http://www.ctan.org/tex-archive/macros/latex/contrib/supported/IEEEtran/ [8] FLEXChipSignalProcessor(MC68175/D),Motorola,1996. [9] “PDCA12-70datasheet,”OptoSpeedSA,Mezzovico,Switzerland. [10] A.Karnik,“Performance of TCPcongestion controlwith rate feedback:TCP/ABR and rate adaptive TCP/IP,”M.Eng.thesis,Indian Instituteof Science,Bangalore, India, Jan. 1999. [11] J.Padhye, V. Firoiu, andD.Towsley, “A stochastic modelof TCPReno congestionavoidanceand control,” Univ. of Massachusetts, Amherst, MA,CMPSCITech. Rep. 99-02, 1999. [12] WirelessLANMediumAccessControl(MAC)andPhysicalLayer(PHY)Specification,IEEEStd.802.11,1997.

Copyright

Copyright © 2025 Er. Maneesh Thakur, Prof. Himmi Gupta. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.