scholarly journals Experimental Analysis of Seismic Performance of Masonry Shear Wall Reinforced with PP-Band Mesh and Plastering Mortar under In-Plane Cyclic Loading

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Qiang Zhou ◽  
Lingyu Yang ◽  
Wenyang Zhao

Masonry structures are widely used in developing countries due to their low cost and simple construction, especially in remote areas, where there are a large number of houses without seismic measures. These buildings are prone to collapse and cause a lot of casualties, even under the action of small earthquakes. For the reinforcement of this structure, a cheap, effective, and easy-to-construct reinforcement method is urgently needed. Therefore, this article studies the reinforcement method of polypropylene bands (PP-bands). We have carried out low-frequency cyclic loading tests for two PP-band reinforced masonry walls and two compared masonry walls. We mainly studied the influence of PP-band and different compressive strengths of plastering mortar on the masonry wall’s seismic capacity. The seismic indicators mainly studied in this article include ultimate bearing capacity, energy dissipation capacity, stiffness degradation, and hysteresis characteristics. The experimental results show that the PP-band can greatly enhance the seismic capacity of the masonry wall. The ultimate bearing capacity, energy dissipation capacity, and displacement ductility of the PP-band reinforced wall are increased by 38%–48%, 22%–47%, and 138%–226%.

Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 2942
Author(s):  
Yun Liu ◽  
Gonglian Chen ◽  
Zhipeng Wang ◽  
Zhen Chen ◽  
Yujia Gao ◽  
...  

Autoclaved aerated concrete (AAC) self-insulation block masonry is often used for the infill walls in steel and concrete frame structures. To work together with the frame under earthquake action, it is essential to understand the seismic behavior of AAC self-insulation block masonry walls. In this paper, six AAC self-insulation block masonry walls were experimentally studied under the pseudo static test. The load-displacement hysteretic curves were drawn with the test data. The failure characteristics, loading capacity, stiffness degeneration, energy dissipation capacity and hysteretic behavior are analyzed. The results indicate that the blocks underwent internal failure due to the lower strength with a larger size, but the walls had good energy dissipation capacity with a rational bearing capacity. Accompanied by the influence of vertical compressive stress on the top surface of the walls, the cracking resistance, ultimate bearing capacity, deformability and energy dissipation capacity of the walls were affected by the masonry mortar joints. Comparatively, the walls with thin-layer mortar joints had better seismic performance than those with insulation mortar joints or with vertical joints filled by mineral wool plates. Finally, the shear capacity of the walls under seismic load is evaluated referring to the formulas of current design codes for masonry walls.


2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Lianjie Jiang ◽  
Guoliang Bai

The cumulative damage behavior of SRC columns under far-field long-period ground motions was simulated and studied by quasi-static tests with the same displacement for 10 times. Quasi-static tests of 8 SRC columns were conducted under the horizontal cyclic loading with the same displacement for 10 times or 3 times, and then the effects of steel ratio, stirrup ratio, axial compression ratio, and number of cyclic loading on the cumulative damage of SRC columns under the far-field long-period ground motions were studied. The results showed that the number of cyclic loading had little effect on the peak load of the specimens, but had a significant effect on the deformation capacity, stiffness degradation, and energy dissipation capacity. Compared with the specimens after 3 cycles, the displacement ductility coefficient of specimens after 10 cycles was reduced by about 20%–26%, the ultimate hysteresis energy dissipation was reduced by 35%–48%, while the stiffness degradation rate was accelerated. After the peak load, the cumulative damage caused by multiple cyclic loading with the same displacement was more significant, which aggravated the reduction of bearing capacity and stiffness degradation. The smaller the steel ratio and stirrup ratio, the larger the axial compression ratio, and the greater the reduction of the bearing capacity and stiffness of specimens. However, accumulated damage caused by multiple cyclic loading with the same displacement had a slight impact on the energy dissipation capacity. Increasing the steel ratio and stirrup ratio can effectively improve the deformation capacity and energy dissipation capacity of the specimens and reduce the bearing capacity and stiffness degradation caused by cumulative damage.


2014 ◽  
Vol 684 ◽  
pp. 195-201
Author(s):  
Zhen Lei ◽  
Yong Wang ◽  
Jun Tong Qu

FRP strength technique can increase the lateral strength of masonry walls, but the effect of the presence of pre-damage in the walls before retrofitted has not been studied. In this study, the experimental results from two half-scale RC-brick masonry walls with opening retrofitted with BFRP composite strips are presented. One wall was initially damaged in shear loading up to its maximum strength, and then repaired with BFRP sheets; another one was directly strengthened with BFRP sheets in the same strengthening configuration. All the walls were subjected to cyclic in-plane shear loading up to failure. Compared to the strengthened walls, the repaired masonry wall has almost the same failure mode and FRP strain rule, and slightly lower lateral strength and deformation capacity as well as energy dissipation capacity.


2012 ◽  
Vol 174-177 ◽  
pp. 701-705
Author(s):  
Ya Feng Yue ◽  
Wei Huang ◽  
Dong Zhao

Low frequency cyclic horizontal load experiments have been carried out on the sandwich insulation (ECW-8) and ordinary (ECW-1) multi-ribbed composite wallboard. Mechanical properties of two specimens such as bearing capacity, energy dissipation and failure modes were studied. Two specimens are both shear failure. The cracking load of insulation wallboard increases by 29.1% than ordinary wallboard. The initial stiffness of insulation wallboard is 1.38 times of ordinary wallboard. The ultimate bearing capacity and energy dissipation performance has little difference between them.


2010 ◽  
Vol 150-151 ◽  
pp. 571-575
Author(s):  
Yun Peng Chu ◽  
Yong Yao ◽  
Shu Lian Xiao ◽  
Yue Chen

As a key part in concrete-filled steel tubular frames, the seismic behavior of joints between concrete-filled steel tubes and beams needs more research because of the complexity of stress under the reciprocating load. the behavior of 9 strengthened joints connecting concrete-filled steel tube with H-shaped steel beam have been analyzed under reversed cyclic loading condition by using finite element analysis software ANSYS, and the result show that: (1) The ultimate bearing capacity, energy dissipation capacity and ductility of strengthened joint are obvious better than that of ordinary welded joint; (2) Compared to concrete-filled steel tube the ultimate bearing capacity, energy dissipation capacity and ductility of double-layer concrete-filled steel tubes are better; (3) For the joints connecting double-layer concrete-filled steel tubes with beams, the shape of inner tube have certain effect on the ultimate bearing capacity but little on the energy dissipation capacity and ductility. (4) The shape of stiffened plate has significant influence on the ultimate bearing capacity, energy dissipation capacity and ductility of nodes.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2961
Author(s):  
Moein Rezapour ◽  
Mehdi Ghassemieh ◽  
Masoud Motavalli ◽  
Moslem Shahverdi

This study presents a new way to improve masonry wall behavior. Masonry structures comprise a significant part of the world’s structures. These structures are very vulnerable to earthquakes, and their performances need to be improved. One way to enhance the performances of such types of structures is the use of post-tensioning reinforcements. In the current study, the effects of shape memory alloy as post-tensioning reinforcements on originally unreinforced masonry walls were investigated using finite element simulations in Abaqus. The developed models were validated based on experimental results in the literature. Iron-based shape memory alloy strips were installed on masonry walls by three different configurations, namely in cross or vertical forms. Seven macroscopic masonry walls were modeled in Abaqus software and were subjected to cyclic loading protocol. Parameters such as stiffness, strength, durability, and energy dissipation of these models were then compared. According to the results, the Fe-based strips increased the strength, stiffness, and energy dissipation capacity. So that in the vertical-strip walls, the stiffness increases by 98.1%, and in the cross-strip model's position, the stiffness increases by 127.9%. In the vertical-strip model, the maximum resistance is equal to 108 kN, while in the end cycle, this number is reduced by almost half and reaches 40 kN, in the cross-strip model, the maximum resistance is equal to 104 kN, and in the final cycle, this number decreases by only 13.5% and reaches 90 kN. The scattering of Fe-based strips plays an important role in energy dissipation. Based on the observed behaviors, the greater the scattering, the higher the energy dissipation. The increase was more visible in the walls with the configuration of the crossed Fe-based strips.


2013 ◽  
Vol 44 (5) ◽  
pp. 436-448 ◽  
Author(s):  
J. Radnic ◽  
M. Smilovic ◽  
A. Harapin ◽  
M. Sunara

2020 ◽  
Vol 23 (13) ◽  
pp. 2822-2834
Author(s):  
Xian Rong ◽  
Hongwei Yang ◽  
Jianxin Zhang

This article investigated the seismic performance of a new type of precast concrete beam-to-column joint with a steel connector for easy construction. Five interior beam-to-column joints, four precast concrete specimens, and one monolithic joint were tested under reversed cyclic loading. The main variables were the embedded H-beam length, web plate or stiffening rib usage, and concrete usage in the connection part. The load–displacement hysteresis curves were recorded during the test, and the behavior was investigated based on displacement ductility, deformability, skeleton curves, stiffness degradation, and energy dissipation capacity. The results showed that the proposed beam-to-column joint with the web plate in the steel connector exhibited satisfactory behavior in terms of ductility, load capacity, and energy dissipation capacity under reversed cyclic loading, and the performance was ductile because of the yielding of the web plate. Therefore, the proposed joint with the web plate could be used in high seismic regions. The proposed joint without the web plate exhibited similar behavior to the monolithic specimen, indicating that this joint could be used in low or moderate seismic zones. Furthermore, the utilization of the web plate was vital to the performance of this system.


Sign in / Sign up

Export Citation Format

Share Document