底商多层砌体房屋地震倒塌机理及加固方法研究

发布时间：2018-12-07 19:05

【摘要】：我国地震多发且震害严重，震害的主要表现是人员伤亡，而导致人员伤亡的最重要因素是房屋倒塌。汶川地震显示，在我国中小城镇，地震破坏严重的建筑结构类型主要有底商多层砌体结构、多层RC框架结构、多层砖混结构，其中极震区底商多层砌体结构倒塌比率达85%。分析这类房屋倒塌机理，提出相应的抗倒塌设计方法及对既有建筑抗倒塌加固方法十分必要。本文通过汶川地震极震区中底商多层砌体结构好、坏两种典型代表进行深入剖析，通过理论分析、振动台试验、墙片伪静力试验深入剖析了这类结构的倒塌机理，并有针对性的提出了新建房屋房屋的抗倒塌设计方法以及既有建筑的抗倒塌加固方法。主要结果如下：（1）通过实地调研，客观的展示了底商多层砌体结构构造特点和倒塌模式；指出，底商多层砌体底层纵向相对薄弱，沿纵向倒塌模式最为普遍；（2）模型结构地震模拟试验表明：由于典型的底商多层砌体结构底层纵向由三道侧向刚度差异很大的墙体构成，地震荷载按刚度比例分配，导致刚度最大的中间纵墙率先破坏，失去抗侧和承重能力，地震与重力荷载顺序转移到另外两道相对薄弱的墙体，，由于抗力显著不足，倒塌难以避免；（3）通过代表性墙片伪静力试验，定量地测得各道纵墙的抗侧刚度值，结果支持了上述三道纵墙先后个个击破的倒塌机理推断；（4）在前人成果基础上，得到了与试验结果更吻合的各类典型开洞墙片抗侧刚度计算公式，为底商多层砌体的抗倒塌设计和既有建筑抗倒塌加固提供了理论依据；（5）基于上述调查、试验和分析结果，提出了“平衡刚度、增加延性”的抗倒塌设计方法，对既有底商多层砌体进行加固的具体操作方法。
[Abstract]:There are many earthquakes in our country and the earthquake damage is serious. The main manifestation of earthquake damage is casualties, and the most important factor causing casualties is the collapse of buildings. The Wenchuan earthquake shows that in the small and medium-sized towns of our country, the main types of building structures which are seriously damaged by earthquake are multi-story masonry structure, multi-story RC frame structure and multi-story masonry structure, among which the collapse ratio of bottom Shang multi-story masonry structure in the extreme earthquake area is 85. It is necessary to analyze the collapse mechanism of this kind of building and put forward the corresponding design method of anti-collapse and strengthening method for the existing building. In this paper, the collapse mechanism of this kind of structures is deeply analyzed by means of two typical representatives of good and bad multistory masonry structures in the Wenchuan earthquake extreme earthquake region. The collapse mechanism of this kind of structures is analyzed by theoretical analysis, shaking table test and pseudostatic test of wall sheet. The anti-collapse design method of the new building and the anti-collapse reinforcement method of the existing building are put forward. The main results are as follows: (1) through field investigation, the structural characteristics and collapse mode of multistory masonry structure are objectively demonstrated, and it is pointed out that the vertical collapse mode of bottom layer is relatively weak, and the collapse mode along longitudinal direction is the most common. (2) the seismic simulation test of the model structure shows that the seismic load is distributed according to the stiffness ratio because the typical bottom layer of the multistory masonry structure is composed of three walls with different lateral stiffness. As a result, the middle longitudinal wall with the greatest stiffness is the first to destroy and lose its lateral and load-bearing capacity, and the earthquake and gravity loads are transferred to the other two relatively weak walls in sequence, so it is difficult to avoid collapse because of the obvious deficiency of the resistance. (3) through the pseudo-static test of the representative wall, the lateral stiffness of each longitudinal wall is measured quantitatively. The results support the collapse mechanism of each of the three longitudinal walls. (4) based on the previous results, the formulas for calculating the lateral stiffness of typical open-hole walls are obtained, which provide a theoretical basis for the anti-collapse design of multi-story masonry and the anti-collapse reinforcement of existing buildings. (5) based on the above investigation, test and analysis results, the collapse resistance design method of "balance stiffness, increase ductility" is put forward, and the concrete operation method of strengthening existing multi-story masonry is put forward.
【学位授予单位】：中国地震局工程力学研究所
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TU364;TU312.3;TU746.3

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