考虑城市效应的地表结构群地震响应分析(任务书,开题报告,论文18000字)
摘 要
近些年来，随着城市建设的高速发展，城市范围内存在的建筑数量也越来越多，地震作用下城市中密集分布的建筑之间以及建筑与场地环境之间的相互作用效应不容忽视。其中场地-城市体系具有更复杂的场地环境，数量更多的不同类型结构，结构与结构之间，结构与场地之间的相互作用影响规律也更为复杂。因此本文对不同建筑密度、结构类型、地震波类型和幅值下考虑城市效应的地表结构群地震响应进行研究。
首先分别建立土体和结构模型，并进行模态分析，得到场地和结构的自振特性。然后对不同的场地-结构群模型进行瞬态分析，得到不同地震波类型和幅值、不同城市密度和结构类型下土体和结构的响应。经对比分析，结果表明：
（1）城市效应会使地震作用下体系的响应减弱，且城市效应对体系的影响从城市中心到城市边缘逐渐衰减。
（2）结构基频与卓越基频越接近，SCI效应对地表响应的减弱程度越明显；城市密度越大，场地-城市效应越明显；地震波幅值越大，城市效应对地表响应的最大影响程度越大；地震波类型不同，城市效应的影响规律也不同。
（3）不同结构类型和不同地震波类型时，城市效应对土体深度方向的响应影响十分接近；城市密度越大（从0.09增至0.33），城市效应对土体深度方向加速度响应的影响逐渐增强；地震波幅值越大，城市效应对土体深度方向加速度响应的影响越大。
（4）不同地震波幅值和不同地震波类型时，城市效应对结构响应的影响十分接近；城市效应对结构加速度响应的影响随着结构高度的增大而增强；城市效应对结构响应的影响随着城市密度的增大（从0.09增至0.33）而逐渐增强。
论文的研究方法和结果对一致激励下考虑场地-城市效应的真实城市模型的地震响应规律研究有一定的帮助。
关键词：场地-城市相互作用；城市效应；地表结构群；地震响应
Abstract
In recent years, with the rapid development of urban construction, there are more and more buildings in the urban area. The interaction among densely distributed buildings of cities and the interaction between buildings and site environments cannot be ignored. Among them, the site-city system has a more complex site environment, a larger number of different types of structures, and the interaction between structure and site is more complicated. Therefore, this paper studies the seismic response of surface structure groups considering urban effects under different building densities, structure types, seismic wave types and amplitudes.
Firstly, the soil and structure models are established separately, and the modal analysis is carried out to obtain the natural vibration characteristics of the site and structure. Then, the transient analysis of different site-structure models is carried out to obtain the response of soil and structure under different seismic wave types and amplitudes, different urban densities and structural types. After comparative analysis, the results show that:
(1) The urban effect will weaken the response of the system under the earthquake, and the impact of the urban effect on the system will gradually decline from the urban center to the urban edge.
(2) The closer the fundamental frequency of the structure is to the superior fundamental frequency, the more obvious the weakening of the SCI effect on the surface response is; the greater the density of the city, the more obvious the site-city effect is; the greater the amplitude of the seismic wave, the greater the impact of the urban effect on the surface response. The greater the degree; the different types of seismic waves, the different laws of urban effects.
(3) When types of structures and types of seismic are different, the effect of urban effect on the depth direction of the soil is very close; as the density of the city is increased(from 0.09 to 0.33), the effect of urban effect on the acceleration response of the depth direction of the soil is gradually enhanced. The larger the amplitude of the seismic wave, the greater the influence of the urban effect on the acceleration response of the soil depth direction.
(4) When different seismic wave amplitudes and different seismic wave types, the effect of urban effect on structural response is very close; the effect of urban effect on structural acceleration response increases with the increase of structural height; the influence of urban effect on structural response gradually enhanced with the increase in urban density (from 0.09 to 0.33).
The research methods and results of the thesis are helpful to the study of the seismic response law of the real city model considering the site-city effect under the consistent incentive.
Key words: Site-city interaction; urban effect; surface structure group; seismic response
目 录
第1章 绪论 1
1.1 引言 1
1.2 国内外研究现状 1
1.3 研究内容 5
第2章 计算模型 7
2.1 土体模型 7
2.2 结构模型 8
2.3 地震波输入 11
2.4 工况设置及测点布置 12
2.5 小结 14
第3章 计算结果及分析 15
3.1 模态分析 15
3.2 场地放大效应分析 17
3.3 不同结构类型时体系响应分析 20
3.4 不同城市密度时体系响应分析 27
3.5 不同地震波幅值时体系响应分析 31
3.6 不同类型地震波时体系响应分析 34
3.7 小结 37
第4章 结论与展望 38
4.1 结论 38
4.2 展望 39
参考文献 41
致谢 44
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