高聚物防渗墙土质堤坝抗震性能研究

发布时间：2018-12-13 06:42

【摘要】：高聚物防渗墙是针对土质堤坝除险加固需要研发的防渗加固新技术,具有快捷、轻质、高韧、耐久、微创、环保等优点,正逐渐大规模应用于土质堤坝除险加固,产生了良好的社会、经济和环境效益,有很大的推广应用价值。本文针对这一新技术目前研究的盲区及震区应用推广的关键点——动力特性及抗震性能展开研究。论文从室内试验、模型试验、数值模拟、理论分析等诸多方面入手,着重研究了高聚物防渗墙土质堤坝地震响应特性及其抗震性能,完成的主要工作如下:(1)应用压电陶瓷弯曲元测试技术研究了高聚物注浆材料动力特性。解决了影响精确测试高聚物注浆材料剪切波速的关键问题。测试得到了不同密度下高聚物注浆材料的动剪切波速及其动剪切模量,给出了工程中快速判定高聚物防渗墙动剪切模量的方法。对比分析了动、静弹性模量,给出了两者之间的二次多项式函数关系。讨论了高聚物注浆材料和筑坝黏土动模量的相关性。(2)进行了原型材料防渗墙土质堤坝动力离心试验方法的研究。设计了防渗墙土质堤坝非等应力模型相似关系。基于统计学单因素方差分析方法,设计了用于动力离心试验的高聚物防渗墙模型,基于土工离心模型试验原理,设计了动力离心模型专用微粒混凝土。经试验测试两组防渗墙物理、力学特性均符合动力离心试验要求。(3)基于动力离心试验成果研究了高聚物防渗墙土质堤坝和混凝土防渗墙土质堤坝在超重力和地震作用下的地震响应特征。在分析两组防渗墙墙体动应力、坝体加速度、坝顶沉降、坝体超孔隙水压力及动土压力增量等地震响应特征的基础上,重点研究了两组墙体、坝体地震反应异同点。在试验中观察到混凝土防渗墙的破坏现象,找出了传统防渗墙土质堤坝抗震不利部位。(4)研究了高聚物防渗墙土质堤坝抗震性能。利用ABAQUS有限元软件,结合弯曲元试验得出的高聚物注浆材料动力特性,建立了基于黏弹性人工边界地震波输入方法和考虑土体黏弹性的高聚物防渗墙土质堤坝三维数值模型,利用试验结果验证了模型的正确性和合理性。获得了高聚物防渗墙及其土质堤坝的地震响应特性,计算结果联合试验结果明确了高聚物防渗墙土质堤坝抗震性能及相关机理。(5)进行了地震作用下高聚物防渗墙多目标函数的密度优化设计。提出了高聚物防渗墙抗震性能安全系数的概念,将基于图解法的多目标优化方法应用于高聚物防渗墙优化设计。以地震作用下高聚物防渗墙抗震性能好、工程造价低为目标,建立了高聚物防渗墙抗震安全性和经济性为组合的优化模型,进行了高聚物防渗墙墙体材料密度的优化设计,为地震作用下高聚物防渗墙密度优化提供了一种简洁、直观的优化计算方法。
[Abstract]:Polymer impervious wall is a new anti-seepage and reinforcement technology that needs to be researched and developed for danger removal and reinforcement of earthen dikes and dams. It has the advantages of fast, light, high toughness, durability, minimally invasive, environmental protection, etc., and is gradually being applied in large scale to earth dikes and dams for danger removal and reinforcement. It has good social, economic and environmental benefits, and has great application value. In this paper, the dynamic characteristics and seismic performance of the blind area and the application and extension of the new technique are studied. Based on laboratory test, model test, numerical simulation, theoretical analysis and so on, the seismic response characteristics and seismic performance of polymer impervious wall earth dike are studied in this paper. The main work is as follows: (1) the dynamic properties of polymer grouting materials are studied by means of piezoelectric ceramic bending element test technique. The key problem affecting the accurate measurement of shear wave velocity of polymer grouting materials is solved. The dynamic shear wave velocity and dynamic shear modulus of polymer grouting materials with different densities are obtained. The method of determining the dynamic shear modulus of polymer impervious walls in engineering is presented. The dynamic and static modulus of elasticity are analyzed, and the quadratic polynomial function between them is given. The correlation between polymer grouting material and dynamic modulus of damming clay is discussed. (2) the dynamic centrifugation test method of impervious wall earth dike with prototype material is studied. The similarity relation of non-equal stress model of impervious wall earth dike is designed. Based on the single factor variance analysis of statistics, the polymer impervious wall model for dynamic centrifugation test was designed. Based on the principle of geotechnical centrifugal model test, the special particulate concrete for dynamic centrifugal model was designed. Two groups of cutoff wall physics were tested, The mechanical properties all meet the requirements of dynamic centrifugation test. (3) based on the results of dynamic centrifugal test, the seismic response characteristics of polymer impermeable wall earth dike and concrete impervious wall earth dike under the action of hypergravity and earthquake are studied. Based on the analysis of seismic response characteristics of two groups of wall walls, such as dynamic stress, acceleration of dam body, settlement of dam top, excess pore water pressure of dam body and increment of dynamic earth pressure, the similarities and differences of seismic response of two groups of walls and dam body are studied emphatically. The failure phenomenon of concrete impervious wall is observed in the experiment, and the unfavorable seismic position of the traditional impervious wall earth dike is found. (4) the seismic behavior of polymer impervious wall earth dike is studied. By using ABAQUS finite element software and the dynamic characteristics of polymer grouting material obtained by bending element test, a three-dimensional numerical model of polymer impervious wall earth dike based on viscoelastic artificial boundary seismic wave input method and considering soil viscoelasticity is established. The correctness and rationality of the model are verified by the experimental results. The seismic response characteristics of polymer impervious wall and its earth dike are obtained. The calculated results show that the seismic behavior and related mechanism of polymer impervious wall earth dike are clear. (5) the density optimization design of multiobjective function of polymer impervious wall under earthquake action is carried out. The concept of safety factor for seismic performance of polymer impervious wall is proposed. The multi-objective optimization method based on graphic method is applied to the optimum design of polymer impervious wall. With the aim of good seismic performance and low engineering cost of polymer impervious wall under earthquake, an optimization model of seismic safety and economy of polymer impervious wall is established, and the optimum design of material density of polymer impervious wall is carried out. This paper provides a simple and intuitive method for optimizing the density of polymer impervious wall under seismic action.
【学位授予单位】：郑州大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TV312

【相似文献】