侧向连续开孔地下综合体地震响应分析(任务书,开题报告,论文15000字)
摘要
随着城市的发展,地上建筑群逐渐区域饱和,人们开始着眼于地下结构的深入开发,地铁车站作为主要的公用建筑其运营长人流量大,往往会与周围地下空间开发结构连通形成地下综合体,为了合理开发利用以地铁车站为核心的地下综合体结构,方便人们通行,在地铁车站与地下空间开发结构中间侧墙上进行开孔,开孔必定会对结构抗震性能产生影响,因此对其地震响应分析是有必要的。
本文以相关实际工程为背景,利用有限元分析软件ABAQUS建立三维模型,分别建立了自由场/标准车站/侧向一跨开孔地下综合体/侧向两跨开孔地下综合体/侧向三跨开孔地下综合体共五类工况,分别输入0.1gEL波/0.2gEL波/0.1g上海人工波进行计算,并对各类工况的计算结果从加速度时程、峰值加速度、能量、位移以及相对位移和柱端弯矩等角度对比分析,研究了地下结构对与土体地震响应的影响同时确定其空间效应以及抗震薄弱部位,探讨不同开洞方式对结构整体抗震性能的影响。结论主要包括:
(1)地下综合体地表正中点加速度大于标准车站和自由场,地下结构对地表的水平加速度响应有影响,在本文建立的模型中表现标准车站宽度的4.5倍和地下综合体宽度的2.7倍。
(2)地下结构对沿土体纵向水平加速度响具有一定影响范围,在本文建立的模型中表现为结构纵向深度2.7倍。
(3)地下结构改变了土体的能量分布情况,具体表现为有地下结构存在的情况下,能量集中分布在地下结构附近。
(4)由于端墙的存在,会对地下结构产生空间效应影响,使结构刚度发生变化,在本文建立的模型中表现为带地下开发结构的车站结构约为2/3倍的结构宽度,标准车站受端部影响的结构空间效应范围约为2倍的结构宽度。
(5)地下综合体中车站部分的层间位移角相对于标准车站而言其值较大,侧向开孔削弱了其抗震性能。
(6)侧向开孔导致地下综合体的车站部分结构刚度削弱,其柱端弯矩响应明显增大,而不同开孔大小对地下结构的影响并不明显,但能够看出随着孔洞增大结构刚度随之削弱。
关键词:地震响应;地下综合体;一致地震动;侧向开孔
Abstract
With the development of the city, people are beginning to focus on the deeplydevelopmentof underground structuresbecause the ground buildings are gradually saturated. Metro stations, as the main public buildings, have large operating populations and often connect with the surrounding underground development structures to form underground complexes. In order to rationally develop and utilize the underground complex structure with the subway station as the core. the opening is made in the middle side wall of the subway station and the underground space development structure to facilitate the passage ofpeople. The opening will definitely affect the seismic performance of the structure. Seismic response analysis is necessary.
Based on the relevant practical engineering, this paper uses the finite element analysis software ABAQUS to establish a three-dimensional model, and establishes a free-field/underground complex with lateral one-span openings/underground complex with lateral two-span openings/underground complex with lateral three-span openings. There are five types of working conditions across the open-hole underground complex, which are input with 0.1g EL-Centro waves/0.2gEL-Centro waves/0.1g Shanghai waves.The calculation results of various working conditions analysis from acceleration time history, acceleration amplitude, energy and displacement and the bending moment of the column. The influence of the underground structure on the seismic response of the soil is studied. The spatial effect and the weak parts of the structure are determined. The influence of different lateral opening methods on the overall seismic performance of the structure is discussed. The conclusions mainly include:
(1) The underground complex results in the mid-point acceleration of the surface is larger than the standard station and the free-field, and the underground structure has a certain influence range on the horizontal acceleration of the surface. In the model established in this paper, the standard station width is 4.5 times and the underground complex width is 2.7 times.
(2) The underground structure has a certain influence range on the vertical horizontal acceleration response along the soil. In the model established in this paper, the longitudinal depth of the structure is 2.7 times.
(3) The underground structure changes the energy distribution of the soil, which is manifested in the presence of underground structures, and the energy is concentrated in the vicinity of the underground structure.
(4) Due to the existence of the end wall, the spatial effect of the underground structure will be affected, and the structural rigidity will change. In the model established in this paper, the station structure with the underground development structure is about 2/3 times the structural width, and the standard station receiving end The structural spatial effects affected by the ministry are approximately 2 times the structural width.
(5) The interlayer displacement angle of the underground complex is smaller than that of the standard station, and the lateral opening weakens its seismic performance.
(6) The lateral opening causes the structural rigidity of the station part of the underground complex to be weakened, and the bending moment response of the column end is obviously increased. The influence of different opening sizes on the underground structure is not obvious. As the hole increases, the structural stiffness is weakened.
Key words:Seismic response; underground complex; uniform ground motion; lateral opening
目录
第1章绪论 1
1.1引言 1
1.2国内外研究现状 1
1.2.1地下结构抗震研究进展 1
1.2.2国内外对于复杂地下结构抗震的分析实例 2
1.2.3结语 2
1.3研究的基本内容、目标、拟采用的研究分析方法 3
1.3.1研究内容 3
1.3.2研究目标 3
1.3.3拟采取的技术方案 3
第2章计算模型及计算工况 4
2.1计算模型 4
2.1.1计算范围及边界条件设置 4
2.1.2材料参数及本构模型 6
2.1.3单元类型及网格划分 6
2.1.4阻尼设置及动力时步确定 6
2.2计算工况 7
2.3监测方案 9
2.3.1自由场工况监测方案 9
2.3.2标准车站-土体工况监测方案 10
2.3.3侧向一跨开孔地下综合体-土体工况监测方案 11
2.3.4侧向两跨开孔地下综合体-土体工况监测方案 12
2.3.5侧向三跨开孔地下综合体-土体工况监测方案 12
第3章计算结果及分析 13
3.1模态分析 13
3.2土体地震响应分析 13
3.2.1地表正中点加速度分析 13
3.2.2地表横向水平加速度幅值变化分析 15
3.2.3地表横向水平能量变化分析 17
3.2.4土体深度方向水平加速度幅值变化分析 18
3.2.5土体深度方向位移变化分析 19
3.2.6土体深度方向水平能量变化分析 20
3.3车站及地下综合体地震响应分析 21
3.3.1顶板水平加速度分析 21
3.3.2变形分析 24
3.3.3柱顶水平弯矩变化分析 27
3.4小结 34
第4章结论与展望 35
4.1结论 35
4.2展望 35
参考文献 37
致谢 39 |