Study On Settlement Distortion Characteristics Of Xi'an-TongGuan Expressway Connection Sections And The Foundation Treatment

With the sustained and rapid development of the national economy in China, the number of the cars on the road is constantly increasing. The original road construction can't meet the increasing traffic demands and needs to be broadened urgently. Due to the different characteristics and different consolidation extent and compression between new roads and old ones, different settlement appears between them, which leads to vertical cracks at new-old fringe zone and road surface. To solute the important technical problem of highway widening project, this paper systematically researched on the interaction between new and old embankments by methods of in-site test, numerical simulation and theoretical analysis, with the example of the widening project of Xi'an-Tongguan Highway. The main work and conclusions can be given as follows:(1) By the methods of geological reconnaissance and soil mechanics assay in the selected typical sections, researched on the variation regularity of engineering properties of the ground under new and old embankments.(2) Analysed the stress-strain behavior of embankments widening with soil mechanics, and derived the calculating method of the stress-strain at new-old fringe zone and the characteristics of the embankments' deformation behavior under the stress-strain, applying the superposition principle of elasticity theory.(3) Researched the variation regularity of the settlement of new and old embankments on the base of data-analysis of stress-strain behavior, and provided the scientific basis of suitable embankment treatment methods.(4) The soft foundation treatment effect was evaluated scientifically through comparing the treatment condition with the observed data.