重力坝动力荷载下的破坏形式与响应分析

发布时间：2018-12-12 01:46

【摘要】：人类修建堰、坝已有数千年的历史,重力坝是出现最早的坝型之一。1961年瑞士就建成了285m高的大迪克桑斯坝,为地球上重力坝坝高之最；我国于2006年建成的三峡大坝举世瞩目,是当今世界上最大的混凝土实体重力坝,坝体高度为181m。坝体的高度随人们的需求逐渐增加,大坝的安全性越来越成为水工建筑设计师们的重点考虑因素。本文以某工程高重力坝为例,探讨了坝体在地震及爆炸的偶然因素作用下的动力响应特性,具体内容如下：(1)凭借ANSYS软件,建立三维整体坝段群重力坝模型,对空满库情况下各静动力工况相应组合,分析该混凝土重力坝整体坝段群的地震响应,重力坝整体坝段群的设计是否符合抗震要求。(2)通过ABAQUS软件建立挡水坝段、底孔坝段和溢流坝段三个典型单独坝段有无配筋的6个二维非线性有限元模型,将数值模拟结果与结构动力模型试验的结果对比分析,充分研究坝体破坏模式,分析重力坝破坏路径。数值模拟的结果与试验结论基本一致,该工程重力坝的抗震配筋措施大大提高了其抗震性能。(3)针对该工程重力坝抗爆,利用有限元分析软件LS-DYNA,建立自由场正常蓄水位状态下挡水坝段两种坝型不同炸药施放位置的流固耦合模型,对不同坝型的重力坝抗爆特性进行了分析与探讨。重力坝上游面的折坡增大了水下接触爆炸对坝体的加速度、速度的动力响应而减小了位移的响应,而无折坡坝体的时程曲线相对平缓。无折坡比有折坡坝型在水下接触爆炸冲击荷载作用下损伤范围更大、更为严重。
[Abstract]:The dam has been built for thousands of years, and gravity dam is one of the earliest dam types. In 1961, Switzerland built 285m high Dicksance dam, which is the highest dam height on the earth. The three Gorges Dam, which was built in 2006 in China, is the largest concrete gravity dam in the world, with a height of 181 m. The height of dam body increases gradually with the demand of people, and the safety of dam becomes an important factor for hydraulic architects. Taking a high gravity dam of a project as an example, the dynamic response characteristics of the dam body under the action of earthquake and explosion are discussed in this paper. The specific contents are as follows: (1) with the help of ANSYS software, the 3D gravity dam model of whole block group is established. According to the corresponding combination of static and dynamic conditions under the condition of empty and full reservoir, the seismic response of the whole dam group of the concrete gravity dam is analyzed, and whether the design of the whole dam group of the gravity dam conforms to the seismic requirements. (2) the water retaining dam section is established by ABAQUS software. Six two dimensional nonlinear finite element models with or without reinforcement in three typical single sections of bottom and overflow dam sections are proposed. The numerical simulation results are compared with the results of structural dynamic model tests, and the failure modes of the dam body are fully studied. The failure path of gravity dam is analyzed. The results of numerical simulation are basically consistent with the experimental results. The seismic reinforcement measures of the gravity dam greatly improve its seismic performance. (3) aiming at the anti-explosion of the gravity dam, the finite element analysis software LS-DYNA, is used. A fluid-solid coupling model of two kinds of dam types with different explosive positions was established under the condition of normal water level in free field. The anti-explosion characteristics of gravity dams with different dam types were analyzed and discussed. The slope of the upstream face of gravity dam increases the acceleration of underwater contact explosion to the dam body and the dynamic response of velocity reduces the response of displacement while the time-history curve of the dam body without slope is relatively flat. The damage range of non-slope dam is larger and more serious than that of non-slope dam under the action of underwater contact explosion.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TV642.3

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