| Factors leading to concealed damages of Huai river embankment crossed by west to east gas pipeline project are synthetically analyzed, based on (1) embankment collapse and empty or loosened area in sand layer around pipeline, (2) stability of s clasping arch and shallow covering layer, and available maximum grouting pressure of fracture grouting. Considering character of grouting method, choosing grouting materials and construction art, cement and clay are adopted for the grouting materials to treat the embankment.Deep horizontal displacement and seepage pressure are monitored during all risk elimination and treatment process, and time-distinction comparison method is proposed to analyze obtained data. Water table change in embankment is calculated with two-layer foundation stable seepage theory, and comparison study between theory calculation and field investigation is conducted. Based on above all, treatment construction effect on embankment and treatment efficiency are evaluated. Analyzing on grouting volume recorded during construction process, field core-drilling sample, standard penetration test and laboratory soil test are performed to study soil mechanical behaviors such as homogeneity, seepage resistance, et al. At last, appraisal is made on risk elimination and treatment by grouting method with cement and clay to Huai river embankment crossed by west to east pipeline project.Both field investigation, laboratory soil test and theory calculation show the good result of risk elimination and treatment by grouting method with cement and clay to Huai river embankment crossed by west to east pipeline project. A successful example is presented to cope with embankment seepage subject like this kind. |
