Issues‎ > ‎Vol.7 No.1‎ > ‎


In plane Shear Strengthening of Clay Masonry Walls with Opening

Sarwat Hassan Ahmed1   , Muhammad Raouf Abdul-Kadir1  

1University of Sulaimani, College of Engineering, Civil Engineering Department

Received 8 July 2019,     Accepted 28 August 2019,      Published 1 April 2020 


In this paper results of testing eight clay brick wall specimens are presented. Seven of the walls contained opening and one wall without opening. The walls were tested under constant uniformly distributed vertical load and gradually increased lateral load. Six walls were strengthened using the following techniques: reinforced concrete frame around the opening, reinforced concrete frame around the opening with the beam extended to the ends of the wall, steel channel frame inside the opening, reinforced concrete frame confining the boundary of the wall (outside confinement), near surface mounted strengthening with (4) mm steel bar and strengthening with ferro-cement.
The test results illustrated that walls strengthened with external frame showed increased lateral load carrying capacity, ductility and toughness compared to non-strengthened wall, and all other strengthened walls showed different ranges of increased shear strength capacity. However, the wall strengthened with ferro-cement did not improve the ultimate lateral load carrying capacity but ductility significantly improved. For the wall strengthened with near surface mounted steel bars, the ultimate lateral load carrying capacity dramatically increased but the lateral displacement did not increase notably. 


Clay brick, Door opening, Ductility, Masonry wall, strengthening materials


1. Nayak, S., & Dutta, S. C. (2015). Improving seismic performance of masonry structures with openings by polypropylene bands and L-shaped reinforcing bars. Journal of Performance of Constructed Facilities, 30(2), 04015003.
2. Farooq, S. H., Ilyas, M., & Amir, S. (2012). Response of masonry walls strengthened with CFRP and steel strips. Arabian Journal for Science and Engineering, 37(3), 545-559.
3. Marcari, G., Manfredi, G., Prota, A., & Pecce, M. (2007). In-plane shear performance of masonry panels strengthened with FRP. Composites Part B: Engineering, 38(7-8), 887-901.
4. Li, T., Galati, N., Tumialan, G., & Nanni, A. (2005). FRP strengthening of URM walls with openings–experimental results. Mason Soc J, 23(1), 47-58.
5. Voon, K. C., & Ingham, J. M. (2008). Experimental in-plane strength investigation of reinforced concrete masonry walls with openings. Journal of structural engineering, 134(5), 758-768.
6. Okail, H., Abdelrahman, A., Abdelkhalik, A., & Metwaly, M. (2016). Experimental and analytical investigation of the lateral load response of confined masonry walls. HBRC Journal, 12(1), 33-46.
7. Elsamny, M. K., Ezz-Eldeen, H. A., & Elmokrany, A. A. (2017)Strengthening Of Brick Walls with Openings during Construction by Steel Wire Mesh around Openings on Both Sides of Wall.  (IOSR-JMCE), 14(3), 131-139
8. Balsamo, A., Di Ludovico, M., Prota, A., & Manfredi, G. (2011). Masonry walls strengthened with innovative composites. Special Publication, 275, 1-18.
9. ASTM C 270 Standard Specification for Mortar for Unit Masonry, 2003
10. ASTM C1314 Standard Test Method for Compressive Strength of Masonry Prisms, 2014
11. ASTM C150-04, Standard Specification for Portland Cement, ASTM International, West Conshohocken, PA, 2004
12. ASTM C33-11/C33M Standard Specification for Concrete Aggregates, 2011
13. ASTM C136 Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates, 2006
14. Lee, L. H., Han, S. W., & Oh, Y. H. (1999). Determination of ductility factor considering different hysteretic models. Earthquake engineering & structural dynamics, 28(9), 957-977.
15. ASTM C 1018 Standard Test Method for Flexural Toughness and First-Crack Strength of Fiber-Reinforced Concrete (Using Beam With Third-Point Loading), 1997 
16. Iraqi Standards IQS No. 24/1988.
17. ASTM C67 Standard Test Method for Sampling and Testing Brick and Structural Clay Tile, 2003
18. ASTM C 109/C 109M Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or [50-mm] Cube Specimens), 2002
19. ASTM C 348 Standard Test Method for Flexural Strength of Hydraulic-Cement Mortars, 2002
20. ASTM C 307 Standard Test Method for Tensile Strength of Chemical-Resistant Mortar, Grouts, and Monolithic Surfacings, 2003
21. British Standards Institution. (2009). BS EN 12390-3:2009 – Testing hardened concrete. Milton Keynes.