Test On The Jet Mixing Pile Used In Soft Road Foundation Treatment And Numerical Analysis

With the development of economy recently , the scale of basic establishment is larger and larger , so a lot of buildings have to be constructed on soft foundation in civil works,transportation and hydro project. To solve the problems of great settlement,poor stability and low bearing pressure on foundation, it is necessary to treat the soft foundation in construction. Dry jet mixing pile is a common measure. The paper incorporates the project of saturated clay treatment that is in the selected road of Luntou to Longxuedao highway in south area of Guangzhou city in order to study the stability, settlement and consolidation in soft foundation treatment. The test of cement-soil is done in order that the property of dry jet mixing pile (DJMP) in soft foundation treatment is discovered .At the same time, how the cement content influences the strength of cement-soil and what relation is between the cement-soil mechanics property and its age, method of curing, and moisture content, magnitude and shape of sample are known. The normal calculation studies stability, settlement and average degree of consolidation of the soft foundation. On the basis of relations between settlement vs. time and average degree of consolidation vs. time, whether the settlement after construction can be admitted is judged. With the linear-elastic model, settlement and consolidation after foundation stabilization are simulated by the way of Biot consolidation in the analysis of finite element method. Something about the DJMP composite foundation such as the increasing and disappearing of pore pressure, the relation between settlement, horizontal displacement and depth, the relation between settlement, horizontal displacement and time, the distribution of pore pressure and stress, the relation between the distribution of stress, settlement and the relation between displacement and the increasing and disappearing of pore pressure are found out by computation. The conclusion of how much speed of filling on the condition of pathway steady is appropriate, whether the settlement after construction can be admitted, how to solve the problem of diversity settlement and so on, can be referenced for design and construction of the test highway.