【作者】 王波；

【导师】 申向东；

【作者基本信息】 内蒙古农业大学 ， 水工结构工程， 2008， 硕士

【摘要】 土石坝这一坝型在世界筑坝史上出现较早,是一种经济的坝型,由于该坝型具有施工简单、工序少、造价低、施工速度快、工作可靠,寿命长、对自然条件适应性强,特别是能适应于较差的地质条件等优点,因而被广泛应用于水利水电拦河坝建设中;也是当今世界建造数量最多、体积最大、高度最高的一种坝型。土石坝在建造和运行过程中一般都要发生较大的变形,尤其是地形突变、地质条件差异较大、坝体施工工艺不同或坝段上升高度不同步时,局部会产生过大的变形和应力,当变形和应力超过坝体材料的承受能力时将产生裂缝。因此,在施工前根据设计和施工方案,模拟坝体施工过程,计算出坝体在不同填筑高度的应力和位移等值线,找出施工期和运行期大坝安全的薄弱环节,对科学、合理地安排施工过程具有技术指导意义。因此,本文基于ANSYS软件,实现了沥青混凝土心墙土石坝应力与变形FEM(finite element method)分析。通过分析得到了如下主要结论:(1)利用ANSYS提供的APDL语言开发的E ? B模型,能够灵活的实现有限元分析的数值计算要求,较好的反映了土体的实际特性,符合土石坝的应力及变形规律。(2)采用增量法模拟土石坝的填筑及蓄水过程,能够较好的反映土石坝的加、卸载及土体的拉力破坏、剪切破坏过程,满足数值计算要求,(3)有限元计算结果表明:竣工期、蓄水期的坝体变形及应力分布规律较为合理,反映了大坝的实际变形及应力分布规律,坝体在竣工期和蓄水期的安全性是可以得到保证的。(4)对深厚覆盖层上沥青混凝土心墙坝的整个施工过程和运行期进行的三维非线性数值模拟,可以为深厚覆盖层上沥青混凝土心墙坝设计提供了一定的科学依据。更多还原

【Abstract】 Earth-rock dam is a kind of dam which appeared early in the history of world construction of dam. It is a sort of economical dam. Being constructed easily, less working procedure, lower cost, fast constructing speed, reassuring work, long working life, easily adapting to the nature condition, especially can adapt to poor geological condition, it has been widely applied in the construction of water conservancy and water and electricity dams. It is also the kind of dam that the most in amount, the largest volume and the highest height in the world.Generally, when being constructed and operating, the earth-rock dam changes its shape a lot. Especially when the landform change largely, having great differences in geological conditions, the body of the dam’s technics is different or the dam’s raising height is different, part of it will have over great deformation and stress. And when the deformation and stress are over the body of the dam’s supporting ability, there will be crack. So, it has a instructional significance to simulate the operating progress of the dam, figure out the stress and displacement contour when the dam has different building heights, and find out the weak link of security during constructing and operating period for scientific and proper arrangement of constructing progress. Therefore, based on ANSYS software, this article puts asphalt concrete wall earth-rock dam stress and deformation FEM analysis into practice. According to the analyses we can draw a conclusion as follows:1.Making use of E-B model from APDL supporting by ANSYS, we could meet the need of Finite element analysis of the numerical flexibly, reflect soil real character which conform to Stress and deformation of the earth dam.2.Using additional method to imitate the retain water process can reflect the loading and unloading of Earth dam and the breaking power of the process in order to finish the count.3.From the result of FEM, the regulation of completing time’s and retaining time’s is reasonable, which reflect the real transformation and regulation. It guarantees the safety during the time of completing time and retaining time.4.Towards the Nonlinear 3-D numerical model from the process and operation time from the thick Asphalt concrete core dam, it can offer scientific evidence to the design of thick Cover on the asphalt concrete core.更多还原