Social contribution through technical development of improvement on seismic performance of confined masonry wall structures being popular in developing countries

本文采用试验、分析、文献和实地调查等方法，对发展中国家普遍采用的约束砌体墙体结构的抗震性能进行了研究。在试验中，所有单跨单层试件均模拟三层建筑首层的应力图，承受反向横向剪力和恒定竖向荷载。1/2.5比例尺试件的砌体墙由带两个孔的粘土砖组成，四周为钢筋混凝土柱和梁。变量包括开孔墙的形式/大小/位置、剪跨比、柱的深度和开孔墙的三种加固方法。测试结果备注如下：1)该结构的抗剪能力主要受砖间砂浆网缝的滑动强度和柱的抗剪强度的影响；2)有开口的墙体在剪切过程中因套筒墙体的滑动而失效(s)，更多的开口和与套筒墙体平面垂直压应力相关的滑动强度是由墙体结构的旋转引起的。3)三种加固方法（在窗口置入木材层合或钢管框架，在窗口置入钢丝网和砂浆护套）均能较好地提高抗剪能力和变形能力；4)两个侧孔的粘土砖能模拟出三个轴向不同的力学行为。采用针对钢筋混凝土结构发展起来的非弹性有限元法对约束砌体结构进行了分析。通过层状砖试件的剪切加载试验，获得了砖间砂浆缝的滑动特性，并根据该特性建立了砖间砂浆缝的剪切-滑动关系曲线。通过对比试验和分析得到的荷载-漂移关系，表明节理面上的压应力对结构的抗剪能力和变形能力有显著影响。少

This study was carried out to investigate the seismic performances of confined masonry wall structures, which are very popular in developing countries, by ways of experiment, analysis, bibliography and field survey.In the experiment, all specimens formed with one-span and one-story were subjected to reversal lateral shear force and constant vertical load simulating stress diagram in the first story of three story building. The specimens with a 1/2.5 scale had a masonry wall consisted of clay bricks with two holes and surrounded by RC columns & beams. The variables were form/size/location of an opening in the wall, shear-span-ratio, depth of columns and three types of strengthening methods for the wall with an opening.The remarks of the test results were follows: 1) shear capacity of this structure effected mainly by sliding strength of mortar mesh joints between bricks and shear strength of columns, 2) walls with an opening failed in shear caused by sliding of sleeve wall (s) in the si … More de of the opening and the sliding strength related to vertical compressive stress in the sleeve-wall plane occurred by rotation of the wall structure, 3) three strengthening methods (inserting a frame made of timber lamination or steel pipes in the window opening, and jacketing with wire-mesh and mortar) showed good improvement on shear capacity and deformability, and 4) clay bricks with two lateral holes could simulate the mechanical behaviors which had difference in three axial directions.This confined masonry wall structure was analyzed by an inelastic finite element method which was developed for reinforced concrete structures. Sliding characteristics of mortar joint between bricks were obtained by shear loading tests for layered brick specimens and a shear-sliding relation curve was modeled from the characteristics. In comparison between load-drift relations obtained from the experiments and analyses, it was cleared that compressive stress on joint planes effected remarkably on the shear capacity and deformability of this structure. Less