Experimental Investigation on the Seismic Behavior of Newly-Developed Precast Reinforced Concrete Block Masonry Shear Walls

Weifan Xu,Xu Yang,Fenglai Wang

doi:10.3390/app8071071

Abstract

Typically, a special type of concrete block with cleaning holes is used in the bottom layer of traditional reinforced masonry shear walls (RMSWs) for mortar cleaning and vertical rebar connection, which results in reduced integrity and weakened structural behavior. In this paper, a precast construction technology was introduced to overcome these shortcomings. The cleaning-hole blocks were eliminated in the newly-developed precast RMSWs. Quasi-static tests on two traditional and two precast fully grouted RMSWs were conducted. The results showed that the flexural capacity of precast walls exhibited about a 10% increase when compared to traditional RMSWs under the same axial compression. Precast RMSWs that failed in flexural mode showed favorable deformation capacity and the displacement ductility value corresponding to 15% strength degradation reached 4.9. The wall stiffness degraded rapidly to 50% of the initial stiffness, K0, at 0.2% drift and, at 0.5% drift, the corresponding stiffness decreased to about 21% K0 at a more gradual rate. Furthermore, precast RMSWs exhibited significant energy dissipation capacity. The experiment suggests that precast RMSWs have a satisfactory seismic performance.

Highlights

As one of the most popular materials, the concrete block is widely used in the world for its low cost and high bearing capacity
Reinforced masonry shear walls (RMSWs) exhibit better seismic performance compared to traditional unreinforced masonry structures due to the existence of horizontal and vertical reinforcement, which results in reinforced masonry shear walls (RMSWs) being widely applied in mid-rise and high-rise buildings [1]
The results proved that the axial load has a detrimental effect on the displacement ductility of shear walls, which is more obvious for precast RMSW

Summary

Introduction

As one of the most popular materials, the concrete block is widely used in the world for its low cost and high bearing capacity. Reinforced masonry shear walls (RMSWs) exhibit better seismic performance compared to traditional unreinforced masonry structures due to the existence of horizontal and vertical reinforcement, which results in RMSWs being widely applied in mid-rise and high-rise buildings [1]. Despite these advantages, it should be noted that traditional RMSWs still have some shortcomings. With respect to traditional construction technology, blocks in the bottom layer of RMSWs must have cleaning holes (see Figure 1a) for the cleaning of redundant mortar occurring during construction and the following vertical reinforcement connection, which causes additional construction procedures and inconvenience of fabrication and results in reduced integrity and weakened structural performance of masonry structures. Lap splices are commonly applied for the connection of vertical rebars in traditional RMSWs of limited construction space at the cleaning holes

Methods

Results

Conclusion