Study On Application And Mechanism Analysis Of Consolidation Grouting Roadbed Work Area Subsidence Disease

Abstract:The grouting is an important technique that has been widely used in the traffic and civil engineering field. A primary use of fracture grouting has been dealt with the collapse and subsidence of highway subgrade, underpinned structures that have suffered from differential settlements, stopped up water by grouting, reinforced pile foundation, subgrade and slope. Most analyses studied on mechanism of grouting, grouting pressures and the uplift caused by grouting were qualitative analysis and numerical simulation. Only a small part of them were about the mechanism of grouting, calculation of grouting pressure and the uplift caused by grouting. Based on the western traffic project "roadbed subsidence rapid repair technology research", research and engineering application of grouting reinforcement in the work zone of highway subgrade are analyzed through theoretical analysis, numerical simulation and engineering application. The main achievements are shown as follows:(1) According to the assumption that the soil obeys the rule of small-strain theory before the soil yields and large-strain theory and non-associated flow rules after soil yields. The stress and strain of the fracture grouting process and the fracture grouting mechanism were analyzed with the theory of cavity expansion. And the fracture grouting pressure calculation formulas under the MC criterion, the SMP criterion, the UN criterion and the MMC criterion were obtained. The reliability of the method presented in the paper was validated through the comparison between the theoretical results and the engineering practice.(2) The uplift caused by grouting was calculated based on stochastic medium theory. The uplift of the grouting was assumed to be caused by cavity expansion of grouting cavity, seepage of slurry and contraction of slurry, which is composed of linear superposition of above influencing factors. The surface lifting of the element effect caused by above factors was calculated firstly, and then the surface uplift displacement of grouting range was obtained through the method of integrating element in the whole grouting area. Thereby, the reliability of the method presented in the paper was validated through the comparison between the theoretical results and the engineering practice. Furthermore, the effect of factors on uplift displacement was illustrated under different grouting conditions.(3) In order to analyze the influence factors of uplift displacement caused by grouting and the rules of these factors, numerical simulation model was established to simulate uplift displacement in accordance with engineering practice. The influence of the grouting radius, grouting pressure, grouting depth, grouting distance, grouting bubble layers and grouting bubble arrangement are analyzed through model comparison. And the best grouting parameter are obtained through the numerical simulation.This panper includes61figures2tables and86references...