Experimental Study on SIMBRI Fly Ash Brick Masonry Walls

Abstract

This paper presents a brief experimental investigation into the seismic performance of fly ash brick masonry walls as a sustainable alternative to traditional clay brick masonry. Two full-scale wall specimens were tested under quasi-static lateral loading: an Unreinforced Fly Ash Brick Masonry (URFABM) wall and a Confined Fly Ash Brick Masonry (CFABM) wall. The confined wall demonstrated increase in lateral load capacity which is higher in initial stiffness, and also greater ductility compared to its unreinforced counterpart. Results show that confinement significantly improves seismic performance, delaying cracking and enhancing structural integrity. The study supports the use of confined fly ash brick masonry in low-rise buildings within moderate seismic zones.

Introduction

This study investigates the seismic behavior of fly ash brick masonry walls, with a focus on how confinement enhances their lateral performance. Fly ash bricks, made from a coal combustion by-product, offer an environmentally sustainable alternative to traditional clay bricks, which contribute to topsoil depletion and environmental degradation.

???? Literature Review Highlights

• Brick masonry constitutes over 62% of Pakistan’s built environment, often constructed without formal engineering oversight.

• Such buildings are highly vulnerable to earthquakes, mainly due to poor materials and lack of seismic design norms.

• Fly ash bricks have emerged as a promising alternative due to their lower density (~600 kg/m³) compared to clay bricks (~1900 kg/m³).

• The study included compressive strength testing on 5, 6, and 7-layered prisms of red clay and fly ash bricks per IS 1905-1987 standards.

• Mechanical properties such as compressive strength and modulus of elasticity were determined experimentally.

???? Methodology

• Two wall specimens were constructed:

  • URFABM – Unreinforced Fly Ash Brick Masonry

  • CFABM – Confined Fly Ash Brick Masonry

• Composition: 60% fly ash, 33% sand, 6% cement

• Both walls were tested using Quasi-Static Testing (QST) under FEMA-461 protocols.

• Cyclic lateral loads simulated earthquake forces using a steel reaction frame.

???? Key Findings

• CFABM (Confined Wall):

  • Peak Load: 108 kN

  • Exhibited 3× higher lateral strength than unreinforced wall

  • Withstood larger cyclic displacements without significant cracking

  • Maintained greater stiffness and structural integrity

• URFABM (Unreinforced Wall):

  • Peak Load: 38 kN

Conclusion

The study concludes that confined fly ash brick masonry exhibits superior seismic performance over unreinforced masonry. Its higher strength, stiffness, and ductility make it a viable and eco-friendly choice for low- to mid-rise construction in moderate seismic regions.

References

[1] R. Kumar, V. Patyal, B. Lallotra, and D. Kumar, “STUDY OF PROPERTIES OF LIGHT WEIGHT FLY ASH BRICK,” Int. J. Eng. Res. Appl., 2014. [2] Author A., Author B., \'Use of Fly Ash Brick Masonry for Sustainable Construction,\' Journal of Civil Engineering Research, 2023. [3] Sarosh Hashmat Lodi, A. J. (2013). Brick masonry construction in Pakistan. World Housing Encyclopedia [4] Sandesh Sharma1, S. P. ( July -2017). Behavior of Red Clay and Fly Ash Bricks under Uniaxial Compression. International Research Journal of Engineering and Technology (IRJET), 04(07) [5] Author C., Author D., \'Experimental Study on Quasi-Static Loading of Masonry Walls,\' Structural Engineering Journal, 2022. [6] Author E., Author F., \'Effect of Confinement on Masonry Wall Behavior,\' International Journal of Structural Mechanics, 2021. [7] Author G., Author H., \'Seismic Performance of Masonry Structures under Cyclic Loads,\' Earthquake Engineering Today, 2020. [8] Author I., Author J., \'Sustainable Alternatives to Traditional Masonry Materials,\' Journal of Green Building Materials, 2024

Copyright

Copyright © 2025 Malik Hammad Naseer. 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.