初始成样含水率对饱和细砂固结与剪切过程的影响  

Effect of Initial Sampling Water Ratio on Consolidation and Shear Process of Saturated Fine Sand

作　　者：郭莹[1,2] 高军程[1] 

机构地区：[1]大连理工大学建设工程学部岩土工程研究所,辽宁大连116024 [2]大连理工大学海岸和近海工程国家重点试验室,辽宁大连116024

出　　处：《防灾减灾工程学报》2013年第5期510-516,共7页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金青年基金项目(50808033)资助

摘　　要：基于亚像素角点检测的数字图像测量方法,能够记录三轴试样表面方块角点的位移,从而获得试样表面每一时刻的应变场。针对采用不同初始成样含水率制备的松、密两种状态的唐山饱和细砂,进行了三轴固结排水剪切试验。利用图像测量系统测量试样的轴向和径向变形,获得了试样在固结排水过程中轴向应变和径向应变之间的变化关系,通过绘制的轴向和径向应变场图,分析了固结排水过程中试样的轴向应变场和径向应变场的变化规律;获得了不同初始成样含水率的饱和试样在剪切过程中的应力应变曲线。试验结果表明:采用不同初始成样含水率制备的饱和试样具有不同的初始结构,以湿装法和干装法制备的试样在固结排水过程中表现出不同的变形特征;初始成样含水率对松砂和密砂在剪切过程中的应力应变关系均有影响,其根本原因是不同初始成样含水率制备的饱和试样具有不同的初始结构性。The digital image measurement method based on sub-pixel accurate corner locator is able to record the displacement of corner of squares on the surface of samples to acquire the strain field on the surface of samples at any time. The triaxial consolidated drained shear tests were conducted for loose and dense saturated Tangshan fine sand sampled with different initial sam- piing water content. By measuring the deformations in the axial and radial direction with digital image measurement system, the change relationship of the axial strain and radial strain during consolidation drained process was acquired. By drawing the field figures of axial strain and radial strain, the change rules of two strain fields were analyzed. The stress-strain curves of saturated samples with different initial sampling water ratio during shear process were obtained. The test results show that saturated samples prepared with different initial sampling water ratio have dif- ferent initial structure, samples prepared with wet method and dry method present different de- formation properties in consolidation drained process. The relations of stress strain during shear process for loose and dense sand are effected by the initial sampling water ratio. The fundamental reason is that saturated samples with different initial sampling water ratio have different initial structure.

关 键 词：数字图像测量 初始成样含水率 饱和细砂 固结排水 应变场 

分 类 号：TU411[建筑科学—岩土工程]