【作者】 张杨；

【导师】 付宏渊；

【作者基本信息】 长沙理工大学 ， 岩土工程， 2009， 硕士

【摘要】 水泥混凝土路面板具有强度高,稳定性好、耐久性好,使用寿命长,养护费用少等优点,但在实际运用中由于差异沉降等原因产生的水泥混凝土路面板局部脱空引起各板支承条件变化,进而产生应力集中现象,加上车辆的反复荷载的作用,极易造成水泥混凝土板的断裂。解决混凝土板断裂的三个主要问题有:工后沉降引起板体支承条件变化和水泥板应力分布;不同支承条件下水泥板的受力与变形;弹性支承条件下水泥混凝土板断裂破坏机理。本文针对这些问题作了一些研究,主要有如下内容:1、对水泥混凝土路面板脱空的成因、断裂类型、断裂准则、断裂机理及路面疲劳寿命计算做了介绍和分析。纵向脱空形态的水泥混凝土路面板,推导出单轴、双轴载弯拉应力σ_x与脱空尺寸等值线图、临界荷位作用下弯拉应力与板厚的关系图、单轴载作用最大弯拉应力与荷位的关系图、超载作用弯拉应力σ_x等值线图。2、介绍了水泥混凝土路面板传力杆模型,采用三维有限元程序,分析了不同脱空尺寸、形态、方位、厚度、荷载等级、传荷能力等因素进行了分析,并分析总结出一些相关规律。3、进行了不同支承条件下混凝土板体断裂破坏的试验研究,分析研究了三种情况下(纵向脱空、横向脱空、边角脱空)及循环荷载作用下应变、位移、土压力的相关规律,并得到了相关计算公式。更多还原

【Abstract】 Cement concrete pavement slabs has lots of advantages,such as high strength, good stability,good durability,long life,low maintenance cost,However,in practical application,because of differences in the settlement and other reasons for the slabs caused local void and boundary conditions change,lead to the stress concentration phenomenon,coupled with the repeated loading of vehicles,cement concrete slabs easily cause the fracture.There are three main issues to solve concrete slab fracture: the settlement which was occurred after construction completed lead to boundary conditions change and stress distribution of cement slabs;the force and deformation of the cement concrete pavement slabs under different supporting conditions;the mechanism on the fracture failure of cement concrete pavement slabs in the elastic supporting conditions.The paper has done some research work about this issue;the main contents of paper are as follows:1、It was introduced and analyzed the reasons of void,fracture type,fracture criterion,fracture mechanism,calculation of fatigue life of cement concrete pavement.Specifically for cement concrete pavement at state of vertical void,derived the isogram of flexural tensile stress(σ_x)with uniaxial and biaxial set at change of void size;derived the diagram of flexural tensile stress with the effect of critical load site at change of slab thickness;derived the diagram of max flexural tensile stress with uniaxial set at change of critical load site and flexural tensile stress(σ_x) with the effect of overload.2、It was introduced the several model of cement concrete pavement slab’s joint pole.Use three-dimensional finite element program,the different of void size,shape, position,thickness,load levels,communication ability and other factors was analyzed, and summarized some of the relevant Law.3、Some related experimental about fracture failure of Cement concrete slabs under different supporting conditions has done.And summarize the impact of the vertical viod,horizontal viod,corner viod and cycle load about fracture features, some relevant calculation formula has get.更多还原