吹填土真空固结变形特性的室内试验

为了研究吹填土在真空预压作用下的固结特性和应力应变关系,设计了室内试验装置.在该装置中,吹填土作为一个土单元进行真空固结,通过测量该吹填土体单元在分级真空荷载作用下的体应变和轴向应变过程来研究吹填土的固结变形特性.试验结果表明,吹填土在真空荷载作用下的固结为等向固结,土体的变形各向同性.各级真空荷载作用下,土体的体应变和轴向应变与真空压力之间呈双曲线关系,孔隙比和真空压力的对数之间呈线性关系,且与初始含水率无关.分级荷载下固结时间和变形量表明,超软土在初始阶段的固结在整个固结过程中占据主导作用.试验结果可用于建立吹填软土在真空荷载作用下的应力应变关系和预测真空加固吹填土的固结沉降值.

Laboratory Tests on Consolidation of Dredger Fill Under Vacuum Load

In order to study the consolidation and stress-strain relationship of dredger fill under vacuum load, a testdevice is designed. In this device, dredger fill consolidates as an element. The consolidation of dredger fill is studiedby measuring both its volume and vertical strains under different vacuum loads. Test results show that both the vacuumloading and the deformation of dredger fill are isotropic. Volume and axial strain are in a hyperbola relationship withvacuum load. The relationship between void ratio and the logarithm of vacuum pressure is linear, which is independ-ent of initial water content. The consolidation time and deformation under different vacuum loads show that the consolidation in the initial stage is the dominant part in the whole consolidation process. The test results can be used toconstruct the stress-strain relationship and predict the settlement of dredger fill under vacuum load.