尼泊尔砖木结构古建筑震害调查与有限元模拟初探
发布时间：2018-11-01 15:30
【摘要】：南亚国家尼泊尔以其独特的古建筑艺术而闻名于世。但该国位于地中海——喜马拉雅地震带上,历史上地震频发。很多古建筑在地震中毁于一旦。从古建筑遗产保护的角度出发,尼泊尔古建筑的抗震研究是非常有必要的。目前国内外对于尼泊尔古建筑的震害研究大多停留在定性的介绍以及归纳上面。采用有限元模拟的建筑多集中在现代砌体以及混凝土结构上。少量对于古建筑的模拟多是单体佛塔式建筑的分析。本文对于常见的尼泊尔砖木结构古建筑进行了深入研究,以九层神庙建筑群为例,对其在大地震中的破坏情况进行调研和有限元模拟的初步探索。九层神庙古建筑群包含了典型砖木佛塔式建筑巴克塔布尔塔与典型回廊式建筑。对于尼泊尔砖木古建筑的抗震研究具有巨大的意义。本文以九层神庙建筑群在4·25尼泊尔地震中受到了严重破坏为切入点,做了如下的工作:1.通过实地调研,较为详尽地介绍了该建筑群的震害情况:西南角的主塔上部三层、东北角塔楼的顶层完全垮塌,东南角塔楼顶层严重倾斜,结构底层多处墙体局部垮塌或发生明显的墙体平面外失稳外闪,门窗洞口及窗间墙裂缝普遍,多达6处整层挑檐塌落,结构总体达到中等以上破坏程度,修复难度大。除震害调研外,本文还进行了受损建筑震动特性现场测试,并详尽地展示了该测试结果,用以检验后文有限元模型的合理性。2.在此基础上本文通过LS-DYNA有限元模拟分析了该建筑群的受损情况。在模拟过程中,本文提出了较为简单实用同时也较为准确的壳单元模拟简化方法:针对于主体承重结构——砌体复合墙以及各楼层椽子砌体楼板使用调整过参数的壳单元建模。而后根据计算结果——模型的模态结果和实际现场结构振动特性测试结果对比一致以及模型四座塔楼震害结果归类和实地震害一致验证了该方法的合理性。3.最后结合调研资料与有限元模拟结果对该类建筑的修复加固提出了相应的建议:在砌体墙内芯加设内置钢筋混凝土圈梁与构造柱;在复合墙中横贯内芯与两外表层砌体设置拉结筋,增强复合砌体墙的整体受力性能;加设抗震缝,采用柔性连接,以消除该建筑群与其他建筑群以及该建筑群内部动力特性不一致部分的碰撞隐患;在新砌筑的砖砌体之间使用高强度砂浆粘结,提高砌体墙强度。
[Abstract]:The South Asian nation of Nepal is famous for its unique ancient architectural art. But the country is located in the Mediterranean-Himalayan seismic belt, the history of frequent earthquakes. Many ancient buildings were destroyed in the earthquake. It is necessary to study the earthquake resistance of ancient buildings in Nepal from the point of view of heritage protection. At present, the research on earthquake damage of ancient Nepalese buildings at home and abroad mostly stays on qualitative introduction and induction. The buildings using finite element simulation are mostly concentrated on modern masonry and concrete structures. A small amount of the simulation of ancient buildings is the analysis of individual pagodas. In this paper, the common ancient buildings of Nepalese brick and wood structures are studied in depth. Taking the nine-story temple complex as an example, the damage situation in the earthquake is investigated and the preliminary exploration of finite element simulation is made. The nine-story temple complex consists of a typical brick pagoda and a typical verandah. It is of great significance to study the earthquake resistance of ancient brick buildings in Nepal. In this paper, the nine-story temple complex was severely damaged in the earthquake of 425 Nepal, and the following work has been done: 1. Through field investigation, the earthquake damage of this building group is introduced in detail: the upper three floors of the main tower in the southwest corner, the top floor of the northeast corner tower completely collapses, and the top floor of the southeastern corner tower sloping seriously. At the bottom of the structure, the local collapse of the wall or the obvious external flicker of the wall outside the plane, the cracks between the door and window openings and windows are common, as many as 6 whole overhanging eaves collapse, the structure is generally above the medium level of destruction, and it is difficult to repair. In addition to the investigation and investigation of earthquake damage, the field test of vibration characteristics of damaged buildings is carried out in this paper, and the test results are presented in detail to verify the rationality of the later finite element model. 2. On this basis, the damage of the complex is analyzed by LS-DYNA finite element simulation. In the course of simulation, a simple, practical and accurate simplified method of shell element simulation is put forward. For the main load-bearing structure, masonry composite wall and each floor rafter masonry floor, the shell element with adjusted parameters is used to model the model. Then, the rationality of the method is verified by comparing the modal results of the model with the measured results of the actual field structure vibration characteristics, classifying the damage results of the four towers of the model and the earthquake damage in the field. 3. Finally, combining the investigation data and the finite element simulation results, the paper puts forward the corresponding suggestions for the restoration and reinforcement of this kind of building: add the reinforced concrete ring beam and the structural column in the core of the masonry wall; In order to enhance the overall mechanical performance of the composite masonry wall, the tension reinforcement is arranged between the inner core and the masonry with two exterior layers in the composite wall. The aseismic joints are added and flexible connections are adopted to eliminate the hidden danger of collision between the building group and other buildings as well as the internal dynamic characteristics of the building group, and to use high strength mortar bond between the new masonry brick masonry to improve the strength of the masonry wall.
【学位授予单位】：中国地震局工程力学研究所
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU-87;TU352.11
[Abstract]:The South Asian nation of Nepal is famous for its unique ancient architectural art. But the country is located in the Mediterranean-Himalayan seismic belt, the history of frequent earthquakes. Many ancient buildings were destroyed in the earthquake. It is necessary to study the earthquake resistance of ancient buildings in Nepal from the point of view of heritage protection. At present, the research on earthquake damage of ancient Nepalese buildings at home and abroad mostly stays on qualitative introduction and induction. The buildings using finite element simulation are mostly concentrated on modern masonry and concrete structures. A small amount of the simulation of ancient buildings is the analysis of individual pagodas. In this paper, the common ancient buildings of Nepalese brick and wood structures are studied in depth. Taking the nine-story temple complex as an example, the damage situation in the earthquake is investigated and the preliminary exploration of finite element simulation is made. The nine-story temple complex consists of a typical brick pagoda and a typical verandah. It is of great significance to study the earthquake resistance of ancient brick buildings in Nepal. In this paper, the nine-story temple complex was severely damaged in the earthquake of 425 Nepal, and the following work has been done: 1. Through field investigation, the earthquake damage of this building group is introduced in detail: the upper three floors of the main tower in the southwest corner, the top floor of the northeast corner tower completely collapses, and the top floor of the southeastern corner tower sloping seriously. At the bottom of the structure, the local collapse of the wall or the obvious external flicker of the wall outside the plane, the cracks between the door and window openings and windows are common, as many as 6 whole overhanging eaves collapse, the structure is generally above the medium level of destruction, and it is difficult to repair. In addition to the investigation and investigation of earthquake damage, the field test of vibration characteristics of damaged buildings is carried out in this paper, and the test results are presented in detail to verify the rationality of the later finite element model. 2. On this basis, the damage of the complex is analyzed by LS-DYNA finite element simulation. In the course of simulation, a simple, practical and accurate simplified method of shell element simulation is put forward. For the main load-bearing structure, masonry composite wall and each floor rafter masonry floor, the shell element with adjusted parameters is used to model the model. Then, the rationality of the method is verified by comparing the modal results of the model with the measured results of the actual field structure vibration characteristics, classifying the damage results of the four towers of the model and the earthquake damage in the field. 3. Finally, combining the investigation data and the finite element simulation results, the paper puts forward the corresponding suggestions for the restoration and reinforcement of this kind of building: add the reinforced concrete ring beam and the structural column in the core of the masonry wall; In order to enhance the overall mechanical performance of the composite masonry wall, the tension reinforcement is arranged between the inner core and the masonry with two exterior layers in the composite wall. The aseismic joints are added and flexible connections are adopted to eliminate the hidden danger of collision between the building group and other buildings as well as the internal dynamic characteristics of the building group, and to use high strength mortar bond between the new masonry brick masonry to improve the strength of the masonry wall.
【学位授予单位】：中国地震局工程力学研究所
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU-87;TU352.11
【参考文献】
相关期刊论文 前10条
1 潘毅;谢丹;袁双;王晓s，
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