百米级高沥青混凝土心墙坝受力特性研究
发布时间：2018-07-18 14:54
【摘要】：沥青混凝土心墙坝以其良好的抗渗性、抗衰老性、抗腐蚀性等成为了水工坝体结构的新兴坝型之一。近年来,越来越多的沥青混凝土心墙坝坝高都突破百米,筑坝过程中在坝体重力、施工荷载和水压力的作用下,大坝会发生较大的不均匀沉降,严重威胁大坝的安全。目前国内百米级高沥青混凝土心墙坝受力特性研究相对较少。因此研究百米级高沥青混凝土心墙坝的受力特性具有重要的工程实践意义。本文的主要研究成果为:(1)首先在ABAQUS的平台上开发了邓肯张E-B本构模型,其次以新疆库什塔依水电站工程为背景,对大坝在竣工期和蓄水期时心墙的受力特性进行了系统地分析,然后对沥青混凝土的E-B本构模型参数进行敏感性分析。结果显示心墙的横河向位移、顺河向位移和大、小主应力均随着E-B模型参数的变化呈现一定的规律性,其中内摩擦角φ、黏聚力c、破坏比R_f和参数k对心墙顺河向位移和垂向位移的影响较大,对心墙大、小主应力影响较小,属于高敏感性参数;而模量指数n对心墙顺河向位移、垂向位移和大、小主应力影响较小,属于低敏感性参数。(2)从沥青混凝土心墙的破坏机理出发,提出利用曲坝曲心墙来代替直坝直心墙以减小心墙拉应力的新方案,同时还建立了心墙曲率分别为9.6×10-5、2.4×10~(-4)和3.8×10~(-4)的三种新坝型。通过对比分析三种新坝型竣工期和蓄水期时心墙的应力和位移变化规律,论证曲坝曲心墙的合理性。结果显示曲坝曲心墙可以明显减小心墙的拉应力,且心墙曲率越大,效果越明显。(3)以直坝直心墙为分析实例,建立坝高分别为50m、130m和150m的三种沥青混凝土心墙坝计算模型,通过对比分析不同坝高下心墙竣工期和蓄水期的受力特点,得出了坝高对心墙受力特性影响的一般规律。结果显示坝高的增加,使得心墙底部的压应力快速增长,同时心墙坝肩两侧的拉应力区也有着进一步扩大的趋势。
[Abstract]:Asphalt concrete core dam has become one of the new dam types of hydraulic dam body for its good impermeability, aging resistance and corrosion resistance. In recent years, more and more asphalt concrete core wall dams have exceeded 100 meters in height. Under the action of dam gravity, construction load and water pressure, the dam will have a large uneven settlement, which will seriously threaten the safety of the dam. At present, there are few researches on the stress characteristics of 100 m high asphalt concrete core dam in China. Therefore, it is of great practical significance to study the mechanical characteristics of 100-meter high asphalt concrete core dam. The main research results of this paper are as follows: (1) first of all, Duncan Zhang E-B constitutive model was developed on Abaqus platform; secondly, based on the Kushtay Hydropower Station project in Xinjiang, the mechanical characteristics of the core wall during the completion and storage periods of the dam were systematically analyzed. Then the sensitivity of E-B constitutive model parameters of asphalt concrete is analyzed. The results show that the horizontal displacement of the core wall, the displacement along the river and the large and small principal stresses show a certain regularity with the change of the parameters of the E-B model. The internal friction angle 蠁, cohesion force c, failure ratio R _ f and parameter k have a greater effect on the downstream and vertical displacement of the core wall, and have less effect on the core wall and small principal stress, which are highly sensitive parameters, while modulus exponent n has a high sensitivity to the displacement of the core wall along the river. The vertical displacement and the large and small principal stresses have little influence on the core wall, which is a low sensitive parameter. (2) based on the failure mechanism of the asphalt concrete core wall, a new scheme of reducing the tensile stress of the core wall by using the curved core wall instead of the straight core wall is put forward. At the same time, three new dam types with the curvature of 9.6 脳 10 ~ (-5) and 3.8 脳 10 ~ (-4) have been established, respectively. The rationality of the curved core wall of curved dam is demonstrated by comparing and analyzing the stress and displacement of the core wall during the completion and storage periods of three new dam types. The results show that the curved core wall of curved dam can obviously reduce the tensile stress of the core wall, and the greater the curvature of the core wall, the more obvious the effect is. (3) taking the straight core wall of the straight dam as an example, the calculation models of three kinds of asphalt concrete core wall dam with the height of 50 m or 130 m and 150 m respectively are established. By comparing and analyzing the stress characteristics of the core wall under different dam heights during the completion and storage periods, the general law of the influence of dam height on the stress characteristics of the core wall is obtained. The results show that the compression stress at the bottom of the core wall increases rapidly with the increase of the dam height, and the tensile stress zone on both sides of the dam abutment of the core wall also has a tendency to expand further.
【学位授予单位】：西安理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV642
[Abstract]:Asphalt concrete core dam has become one of the new dam types of hydraulic dam body for its good impermeability, aging resistance and corrosion resistance. In recent years, more and more asphalt concrete core wall dams have exceeded 100 meters in height. Under the action of dam gravity, construction load and water pressure, the dam will have a large uneven settlement, which will seriously threaten the safety of the dam. At present, there are few researches on the stress characteristics of 100 m high asphalt concrete core dam in China. Therefore, it is of great practical significance to study the mechanical characteristics of 100-meter high asphalt concrete core dam. The main research results of this paper are as follows: (1) first of all, Duncan Zhang E-B constitutive model was developed on Abaqus platform; secondly, based on the Kushtay Hydropower Station project in Xinjiang, the mechanical characteristics of the core wall during the completion and storage periods of the dam were systematically analyzed. Then the sensitivity of E-B constitutive model parameters of asphalt concrete is analyzed. The results show that the horizontal displacement of the core wall, the displacement along the river and the large and small principal stresses show a certain regularity with the change of the parameters of the E-B model. The internal friction angle 蠁, cohesion force c, failure ratio R _ f and parameter k have a greater effect on the downstream and vertical displacement of the core wall, and have less effect on the core wall and small principal stress, which are highly sensitive parameters, while modulus exponent n has a high sensitivity to the displacement of the core wall along the river. The vertical displacement and the large and small principal stresses have little influence on the core wall, which is a low sensitive parameter. (2) based on the failure mechanism of the asphalt concrete core wall, a new scheme of reducing the tensile stress of the core wall by using the curved core wall instead of the straight core wall is put forward. At the same time, three new dam types with the curvature of 9.6 脳 10 ~ (-5) and 3.8 脳 10 ~ (-4) have been established, respectively. The rationality of the curved core wall of curved dam is demonstrated by comparing and analyzing the stress and displacement of the core wall during the completion and storage periods of three new dam types. The results show that the curved core wall of curved dam can obviously reduce the tensile stress of the core wall, and the greater the curvature of the core wall, the more obvious the effect is. (3) taking the straight core wall of the straight dam as an example, the calculation models of three kinds of asphalt concrete core wall dam with the height of 50 m or 130 m and 150 m respectively are established. By comparing and analyzing the stress characteristics of the core wall under different dam heights during the completion and storage periods, the general law of the influence of dam height on the stress characteristics of the core wall is obtained. The results show that the compression stress at the bottom of the core wall increases rapidly with the increase of the dam height, and the tensile stress zone on both sides of the dam abutment of the core wall also has a tendency to expand further.
【学位授予单位】：西安理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV642
【参考文献】
相关期刊论文 前10条
1 杨昕光;张伟;潘家军;陈云;谭凡;;软岩筑沥青混凝土心墙坝的应力变形特性研究[J];地下空间与工程学报;2016年S1期
2 余林;凤炜;何建新;;组合式沥青混凝土心墙坝初探[J];水利规划与设计;2016年09期
3 杨超;党发宁;薛海斌;任R，
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