【作者】 张家国；

【导师】 于志强；

【作者基本信息】 西南交通大学 ， 岩土工程， 2004， 硕士

【摘要】 挡土墙，是为了保证填土或挖方位置稳定而修筑的永久或临时性的墙或类似于墙的一类人工构造物。广泛运用于公路、铁路边坡，水利工程岸堤防护，建筑物四周，矿山坑道等工程中。根据结构形式的不同，挡土墙可分成很多类别，其中衡重式挡土墙由于衡重台的存在，改善了墙体的受力性能，增强了抗滑移能力和抗倾覆能力，而使其运用范围更广。因此，清楚地认识衡重式挡土墙的受力及变形特性、进行准确的计算和设计便具有重要价值。目前，对挡土墙的土压力计算仍沿用经典的库伦土压力理论(C．A．Coulomb，1773)和朗金土压力理论(W．J．Rankine，1857)两大理论。经典土压力理论计算简便，基本能满足工程建设的精度要求；但一些基本假设不符合实际情况，使其适用范围、准确性、可靠性等受到影响。为深化和发展挡土墙的土压力理论，许多学者在经典土压力理论的基础上作了进一步的工作，对粘性土的土压力计算、土压力的非线性分布、破裂面形态、土压力大小及分布规律及影响因素等课题进行了研究。衡重式挡土墙的衡重台使墙背土压力的大小及分布、变化规律有别于一般的重力式挡土墙。目前对衡重式挡土墙的土压力计算采用将上、下墙段分开计算，取矢量和作为墙背总土压力的方法。由于没有考虑上、下墙背土压力的相互影响，而使其误差较大。总的说来，对衡重式挡土墙的认识还不够深入，研究成果较少；对墙背土压力分布规律及影响因素、作用机理的研究，还没有形成系统的理论。对挡土墙土压力的研究，有理论推导、数值计算、现场监测、室内普通模型试验、离心模型试验等途径。离心模型试验由于能有效地模拟重力作用下构筑物的真实性状，反映、表示原型而显示出优越性，同时由于其特殊的时间比尺使其在模拟岩土工程时大大缩短了实验时间，在岩土工程领域得到了广泛的运用。有学者运用数值计算、现场监测、室内普通模型试验进行了衡重式挡土墙的土压力研究。但将离心模型试验运用于衡重式挡土墙土压力的系统研究，还很少有研究成果见诸报端。 本文以318国道一段衡重式挡土墙为原型，运用离心模型实验对衡重式挡土墙的受力及变形特性进行研究。共设计了九组离心模型试验，通过不同影响因素的组合，达到不同的设计意图。实验内容包括土工格栅作用下的墙背土压力及变形变化规律、不同压实系数下的墙背土压力及变形变化规律、不同位移模式下的土压力及变形变化规律，运用自制的位移控制机构，西南交通大学硕士研究生学位论文第日页实现对衡重式挡土墙的受力及变形特性的模拟。 本文的创新点在于，将离心模型试验这种实验手段引入衡重式挡土堵受力及变形机理的研究中，通过自制的位移控制机构，实现对衡重式挡土堵的深入、系统研究。其研究成果可以指导生产实践，具有一定的理论和实践惫义。更多还原

【Abstract】 Retaining-walls,are permanent or temporary walls or structures silimar to walls,built to stabilize the fill or excavation.and widely used in slope of highways and railways, water conservancy projects’ dyke protection, bui I dings around and mining area galleries etc. According to the structural form,there are many sorts of retaining walls,one of which is the retaining wall with equi I ibrator that is used more widely because of the equi I ibrator, and the equilibrator can improve the powered function, strengthen the ant-slope and ant-overturn capacity. So it is of great value to real ize the merchanism of power and doform clearly, to calculate and design accruately. At present, two theories are still used to calculate the soil pressure, which are classic Coulomb soil pressure theory and Rankine soil pressure theory. The classic soil pressure theory can meet the accurate require in the main and the course of calculate is easy, but some fundemental assumes different from reality, which influence the using range, accuracy and reliability etc. Many authors made further works based on classic soil pressure theory,, such as clay’ soil pressure calculation,soil pressure’ nonlinearity distribution, rupture surface’shape and soil presure’ value, distribution law and influence factor, to deepen and develop retaining walls’ soil pressure theory. soil pressure’ value, distribution and development law of the retaining walls with equilibrator are different from commmon retaining walls because of the equilibrator. At present, the whole back soil pressure of the retaining walls with equilibrator is regarded as the vector sum of upper’and bottom’soil pressure after they are calculated seperately. and there are some differences because of non-thought of the influences each other of upper wall and bottom wall. On the who I e. the rea I i zat i on of retaining walls with equilibrator is not too deeply and achievements are little, and there is no systematic theory of back pressure’ distribution law, influence factor and workingmechanism. There are many ways to study retaining walls’ soil pressure, such as theoretical inference, numerical calculation, scene watching, inner common model test and centrifugal model test. Centrifugal model test is used widely in rock and soil area because it has advantages in modeling structures in gravity’ real properties effectly, mirroring and indicating prototape. At the same time , it can shorten the experimental time greatly in modeling rock and soil engineerings because of it’ s special time propot ion. Some authors have studied retaining walls with equilibrator’ s soil pressure by numerical calculation, scene watching and inner common model test.But there are no systemtic study results in papers about the soil pressure of retaining walls with equilibrator through centrifugal model test.In this text, the pressure and deformation of a retaining wall or igined from 318 national road was studied through centrifugal model test. Nine groups of centrifugal model test were designed to satisfied with distinct expermentic aim through different combination of the pressure and deformation’ influence factors. Experiment substance comprises of the varition laws of the back pressure and deformation under the action of geogrid, compacting factor, displacement model, and a displacement control I ing construction was designed to realize the study on the pressure and def ormat i on merchan i sm of reta i n i ng wa 1 1 s with equilibrators.In this text , the new ideas lie in thinking of centrifugal model test as the way to study the pressure and deformation mechanism of retaining walls with equilibrtors,and designing a displacement control I ing construction to satisfied with the thorough and systemtic study. The study results can guide practice, with some theoretical and practice significance.更多还原