长春地区白垩系地层地铁勘察参数的确定

Subway Investigation Parameters Analysis and Determination of Cretaceous Strata in Changchun District

白垩系砾岩及泥岩地层在长春地区普遍存在,但由于砾岩地层现场钻探难以取样进行室内土工试验,泥岩地层由于存在水稳性、膨胀性、崩解性等因素影响,砾岩和泥岩的承载力值、抗剪强度参数指标、渗透系数以及基床系数等参数多以经验数据评估方法为主,在合理准确确定相关参数的问题上存在较大分歧。通过对长春地区白垩系砾岩及泥岩进行原位平板载荷试验、浸水载荷试验以及现场原位剪切试验,获取砾岩、泥岩的承载力值、抗剪强度指标、渗透系数以及现场基床系数值等,为地铁建设工程地质问题分析及设计提供充足的地质依据。

Cretaceous conglomerate and mudstone universally exist in Changchun district, but conglomerate is difficult for sample drilling to do laboratory tests;mudstone is affected by many factors such as water stability, expansibility and slaking;many parameters, such as bearing capacity value, shear test parameter, permeability coefficient and coefficient of subgrade reaction, confirm mainly by empirical data evaluation method, There has a big difference on parameter rationality and accuracy . The article proposed bearing capacity values, shear strength, parameters, permeability and in-situ coefficient of subgrade reaction and so on by in-situ plate loading test, water immersion loading test and in-situ shear test on mudstone and conglomerate of cretaceous strata in Changchun district,, providing a geological reference for subway design and construction.