Analytical and Experimental Seismic Evaluation of Confined Masonry Walls Retrofitted by Steel-Fiber and Polypropylene Shotcrete

Dardaei, Sadegh; Shakib, Hamzeh; Khalaf Rezaei, Mohammad; Mousavi, Mehran

Analytical and Experimental Seismic Evaluation of Confined Masonry Walls Retrofitted by Steel-Fiber and Polypropylene Shotcrete

Document Type : Structural Earthquake Engineering

Authors

Sadegh Dardaei

Hamzeh Shakib

Mohammad Khalaf Rezaei

Mehran Mousavi

Tarbiat Modares University

Abstract

This paper presents experimental and analytical results of in-plane behaviour of confined URM walls retrofitted using steel-fiber and polypropylene shotcrete. In this paper, the experimental programconsists of testing three CURMwalls. The first specimen wall was tested as a reference wall without any retrofitting. The second and third specimens were retrofitted by using a 50 mmthick layer of steel-fiber and polypropylene-fiber shotcrete on one side in order to compare the behavior of them. The stiffness, shear strength, ductility, and failure mode of the wall specimens were determined and compared. The comparison of the tests results indicated that the shear capacity of the retrofitted walls with mesh-reinforced shotcrete and polypropylene shotcrete increased about 92% and 87%, respectively, compared to unretrofitted wall. Therefore, using steel-fiber was found to have considerable effect on the strength as well as the ductility of the wall compared to polypropylene. An analytical study was adapted based on micro finite element modelling to calibrate the behavior of the numerical models with the experimental walls in terms of shear capacity and cracking pattern. The analytical results showa reasonably agreement with the experimental data.

Keywords

Confinedmasonry wall

Seismic Retrofitting

Mesh-reinforced shotcrete

Steel-fiber

Polypropylene-fiber

Micromodelling