Analysis of RC Building Frame with and Without Masonry Infill Walls

Abstract

In countries like India where seismic activity is widespread, reinforced concrete frames with masonry infill walls are a popular technique. In structural analysis, brick walls are usually considered non-structural elements; only their mass fraction is considered and their structural properties such as strength and stiffness are usually ignored. Structures in seismically active areas are very susceptible to severe damage. In addition to bearing capacity, the structure must withstand lateral loads, which can cause significant stresses. Reinforced concrete frames are the most used building materials in the world today. The frames of a framed structure are often filled with rigid materials such as brick or concrete block, usually to form an envelope. In this research paper, we analyze the structure of a G+23-story rectangular 32mx24 base multi-story building with each floor height of 3.2m and various parameters such as slab thickness of 150mm, masonry infill support panel height of 390mm and width of 230mm, external column size 600 mm x 700 mm, internal column size 500 x 600 mm, beam size 500 x 700 mm, with IS code. The four analyzed models, such as Model-I without infill wall structure, Model-II and Model-III are masonry infill walls due to the use of corresponding diagonal support panels such as eccentric rear and eccentric front type, while Model IV diagonal or X -type masonry infill the walls use support panel. In this research, RCC frame structure with and without infill wall is analyzed using Etabs 2021 software and parameters such as seismic zone V, average soil condition, response reduction factor 5, significance factor 1.5 for major building etc. IS-1983. and run four models using the corresponding spectral method with Etabs 2021 software Sum all results in the layer displacement period.

Introduction

I. INTRODUCTION

This file serves as a template, Masonry infill panels are being used in the construction of many Indian structures for both utilitarian and architectural purposes.

Masonry infill walls are often regarded as non-structural elements, and in practice—that is, when the building is intended for loading—their stiffness components are typically disregarded. But when lateral stresses are placed on the structure, infill walls often interact with the frame and also exhibit energy-dissipating qualities when subjected to seismic loads. When lateral loads are applied, masonry walls make the infill more rigid. A composite construction made up of infill walls and a moment-resisting planar frame is referred to as a "infill frame".

Masonry walls are used to create segregation and/or seclusion in the majority of reinforced concrete frame buildings. Since the infill wall is thought to be load-free in conventional practice, its involvement in the analysis and design of the structure is disregarded, and the infill's self-weight is taken into account when designing other structural components.

On the other hand, very high initial lateral stiffness and poor ductility were seen in frames with MI walls. The lateral load transmission mechanism of the structure shifts from a dominating frame action to a dominant lattice effect when the frames are filled with brick walls. This causes the bending moments and axial forces in the frame members to diminish.

A. Objective of Work

1. To investigate the structural analysis effects of G +23 layered structure with and without infill wall.
2. To investigate the effect of masonry infill on the stiffness of the structure.

B. Building Plan Configuration

II. LITRETURE REVIEW

3Mohs Nazim, M. Azeem, and Mohd Abdul Malik (2018): - They looked at three distinct building shapes: rectangular, L, and C, which have respective story counts of 11, 16, and 21 and are both regular and irregular in their plans. Nonlinear Static Analysis was used for all models, and the effect of changing the number of bays with an infill structure without soft storey condition was examined by comparing the bare frame with the infill frame. After completing the work related to hinge formation mechanism, base shear, storey drift, roof displacement, performance points, and time periods, they discovered that the inclusion of an infill wall increases the structure's capacity to support loads by eight to ten times compared to bare concrete.

Sneha Jangave and Kiran Tidke (2016): - The G+7 building's framed structure was examined, and the equivalent diagonal strut method was used to calculate the strut's width. The SAP2000 software was used to analyze the response spectrum method in Seismic Zone-II, and the effects of base shear, storey drift, and displacement were investigated for each model. They saw that RC frame structures with masonry infill, both with and without soft storeys, had higher base shares than bare frames. They also saw that the presence of infill walls greatly reduced the seismic behavior of frame structures and enhanced their strength and stiffness.

Dr. J. REX and S. N. Jaya (2019): - Using Etabs software and several seismic zones in India according to the IS Code, they investigated the G+10 Stories with infill walls. They also looked at storey float, storey share, twisting minutes, and building torsion between the frame with and without infill walls. They discovered that the storey shear analysis of infill walls has higher value for all seismic zone remaining case without infill wall in both X & Y direction, and similar to that, the bending moment has higher value for all zone remaining case without infill wall for both directions of X and Y. The lateral displacement in both directions, X & Y, without using the infill wall, had higher value than with infill walls in different seismic zones. According to

Vasinavi Battul, Mr. Rohit M. Shindhe, et al. (2017), they used SAP2000 software to analyze the seismic performance of an RCC structure. They looked at three and a quarter central openings, two distinct plans of rectangular 15 m x 30 m and square 15 m x 15 m shape of G+3 storeys located in an earthquake region, and pushover analysis was used. In addition to finding that the base shear of the infill structure significantly reduced in the bare frame in the plastic state, they also observed that the infill structure had more initial stiffness and less drift in the elastic state than the bare frame. Finally, they discovered that the infill structure is significantly more effective in low rise buildings compared to high rise buildings.

III. MATHODOLOGY

1. Open Etabs Software.
2. Creating Modelling of RC building
3. Applying property like beam, column, slab dimension and support on structure.
4. Applying Load like Dead load, Live load, seismic load and load combination as per IS code.
5. Getting Various Results
6. Results Analysis
7. Conclusion

IV. PROBLEM FORMULATION 

These are RC buildings, both with and without brick infill walls. Configuration of Building Plans: Floor height: G+23, 24 by 32 meters, 3.2 meters There are six or eight bays total, with four meters separating each bay in each direction. Asset: The dimensions of the beams are 500 by 700 mm, while the outer and inner columns are 600 by 700 mm. The strut for the masonry infill walls is 390 by 230 mm in size, and the slab is 150 mm thick. Techniques of Seismic Analysis: Analysis of Response Spectrum Rectangular in design, there are four variants total—two with and without differently positioned infill walls. The kind of structure is the symmetric seismic parameter. RC structures and masonry infill walls are the same kind of construction. The building with the most storeys is G+23, which is shaped like a rectangle. Use the seismic zone-V, zone factor Z=0.36 and soil site factor 2 for mediums. soil conditions, Importance Factor I = 1.5 (per Table 6's Important Structure), Damping Ratio of 5% (per Table 3 Clause 6.4.2), and Response Reduction Factor (R=5) for the unique steel moment-resistant frame are displayed in Table 7. The Natural Fundamental Period affects the average coefficient of acceleration (Sa/g). The grades are M25 for concrete, Fe-415 for rebar, and Fe-345 for steel. Walls have a dead load of 14.375 KN/m and slabs of 3.75 KN/m2.

Conclusion

1) It is found that the maximum storey overturning moment is at base of the structure as 14724905 KN-m in Model-I without Masonry infill structure, 338587.3791 KN-m in Model-II & Model-III of Masonry infill structure as strut eccentric back and eccentric forward as same overturning moment and 16950285 KN-m in Model-IV with masonry infill with X type of Strut and zero overturning moment at base of the structure along the X direction. 2) As comparing all the Models, the maximum overturning moment found at base of structure is 16950285 KN-m in Model-IV in with infill structure while of minimum storey overturning moment of 14724905 KN-m in Model-I which is without Masonry infill structure of X type of Strut along the X direction. 3) It is observed that, if the number of storey increased, overturning moment at base is also increased. 4) It is seen that the maximum storey overturning moment is at base of the structure as 14783051 KN-m in Model-I without Masonry infill structure, 418250.7833 KN-m in Model-II & Model-III of Masonry infill structure as strut eccentric back and eccentric forward as same overturning moment and 16721860 KN-m in Model-IV with masonry infill with X type of Strut and zero overturning moment at base of the structure along the X direction. 5) As comparing all the Models, the maximum overturning moment found at base of structure is 16721860 KN-m in Model-IV in with infill structure while of minimum storey overturning moment of 14783051 KN-m in Model-I which is without Masonry infill structure of X type of Strut along the Y direction. 6) It is seen that, if the number of storey increased, overturning moment at base is also increased.

References

[1] Trupti S. Shewalkar and Amey R, Khedikar, “Performance Analysis of in filled RC Frames in Earthquake Region Using STAAD.Pro” IOSR Journal of Engineering (IOSRJEN) ISSN (e): 2250-3021, ISSN (p): 2278-8719 PP 66-69 [2] Shriyanshu Swarnkar and Dr. Debarati- “Analysis of Building with Infill Walls” Journal of Civil Engineering and Environmental Technology Print ISSN : 2349-8404; Online ISSN : 2349-879X; Volume 2, Number 9; April – June, 2015 pp 71 – 76 Krishi Sanskriti Publications. [3] Mohd Abdul Malik , M A Azeem , Mohd Nazim Raza-“ Effect of Infill Walls on Seismic Performance of RC Frames”- International Journal of Research and Scientific Innovation (IJRSI) | Volume V, Issue II, February 2018 | ISSN 2321–2705. [4] Kiran Tidke , Sneha Jangave-“Seismic Analysis of Building with and Without Infill Wall”- International Journal of Innovative Research in Science, Engineering and Technology (An ISO 3297: 2007 Certified Organization) Vol. 5, Issue 7, July 2016. [5] S.N. Jaya Kumar, Dr. J. Rex-“Studies On Seismic Resistance Of Rcc Frames With And Without Infill Walls”- Journal of Applied Science and Computations Volume VI, Issue VI, JUNE/2019 ISSN NO: 1076-5131. [6] IS 1893(Part 1): 2002”Criteria for Earthquake Resistant Design Of Structures Part 1 General Provisions and Buildings (Fifth Revision) Bureau of Indian Standards New Delhi.

Copyright

Copyright © 2024 Shripal Tiwari, Prof. Anubhav Rai. 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.