地表结构与地下结构地震响应相互影响分析(任务书,开题报告,论文14000字)
摘 要
随着我国城市对地下空间的推进开发，地下结构与地表结构距离越来越近，二者间的相互影响已不可忽视，地下结构、周围地基土及地表结构构成了一个复杂的相互作用体系，本文将其作为一个整体，建立整体的计算模型，探讨地下结构与地表结构地震时的相互影响，分析整体体系的地震响应规律。
首先根据振动台试验建立了四种有限元模型，即自由场模型、土-框架模型、土-隧道模型及隧道-土-框架模型，通过对试验结果的数值拟合，验证了有限元模型的合理性；然后，分别将三种地震波（EL-Centro波、Taft波及武汉人工波）依次输入至各工况进行计算，并根据计算结果对比分析各工况的加速度响应变化规律，得出地下结构与地表结构对周围场地土的影响规律、地下结构对地表结构的影响规律及地表结构对地下结构的影响规律。结果表明：（1）所建立的四种有限元模型的数值结果与试验结果一致，可以据此进一步计算分析；（2）地下结构的存在对周围土体的动力反应有放大的作用，而地表结构则起着衰减的作用；（3）地表结构的存在对地下结构的地震响应起着衰减的作用；（4）地下结构的存在对地表结构的地震响应的影响，对于结构基础的响应影响是放大作用，对于结构低层的响应影响是衰减作用，对结构高层影响不明显。
论文的研究方法和结果对进一步分析地表结构与地下结构在地震时的相互影响有重要的意义。
关键词：地下结构；地表结构；振动台试验；地震响应；
Abstract
As China's cities to promote the development of underground space, underground structures and surface structures getting closer, mutual influence between the two has not be ignored, underground structures, and surface soil around the foundation structure composing of a complex interaction system. In this paper, a integral computation model was established to explore the interaction between the underground structure and the above ground structure during the earthquake, analyzing seismic response laws of the overall system.
Firstly, four kinds of finite element models, namely free-field model, soil-frame model, soil-tunnel model and tunnel-soil-frame model, are established according to the vibration table test. Through the numerical fitting of the test results, the finite element model rationality. Then, three kinds of seismic waves (EL-Centro wave, Taft wave and Wuhan artificial wave) are respectively input into each model to compute, and according to the computed results, the acceleration response of each model is compared and analyzed. The laws of the influence of underground structure and above ground structure on surface soil around the foundation, and the mutual influence between underground structure and above ground structure, are obtained. The results show, (1)The numerical results of the four finite element models are consistent with the experimental results, which can be further computed and analyzed; (2)The presence of underground structures exerts an enlarged effect on the dynamic response of the surrounding soil, while the surface structure acts as an attenuation; (3)The existence of the surface structure plays a role in decaying the seismic response of the underground structure; (4)The influence of the existence of the underground structure on the seismic response of the above ground structure is that, the effect of the response to the structural basis is the amplification effect, while the response to the lower layer of the structure is the attenuation effect, and the structural impact of the upper layer is not obvious.
The methods and results of this paper have important significance for further analysis of the interaction between above ground structure and underground structure during earthquakes
Key words: Underground structure; Above ground structure; Shaking table test; 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 3
第2章 隧道-土-地表框架结构振动台试验简介 5
2.1 模型试验的类型 5
2.2 模型箱的设计与制作 5
2.3 模型土的设计与制作 6
2.4 结构模型的制作 6
2.5 监测方案 7
2.5.1自由场振动台模型试验 7
2.5.2 土体-框架结构振动台模型试验 8
2.5.3 隧道-土体振动台模型试验 10
2.5.4 隧道-土体-框架结构振动台模型试验 10
2.6 加载制度 10
2.7 小结 11
第3章 基于振动台试验的数值计算模型 13
3.1 计算范围及边界条件 13
3.2 本构模型及计算参数 14
3.3 阻尼设置 15
3.4地震波输入 15
3.5 小结 15
第4章 数值计算结果与试验结果的对比分析 16
4.1 自由场模型结果对比 16
4.2 土-隧道模型结果对比 16
4.3 土-框架模型结果对比 17
4.4 隧道-土-框架模型结果对比 18
4.5 小结 20
第5章 对振动台试验的拟合计算结果及分析 21
5.1 模态分析 21
5.2 瞬态分析 21
5.2.1 自由场模型瞬态分析 21
5.2.2 地下结构对周围场地土的影响分析 22
5.2.3 地表结构对周围场地土的影响分析 25
5.2.4 地表结构对地下结构的影响分析 27
5.2.5 地下结构对地表结构的影响分析 29
5.2.6 地表结构竖向加速度响应 32
5.3 小结 33
第6章 结论与展望 34
6.1 结论 34
6.2 展望 34
参考文献 36
致谢 38 |
