【摘要】 根据优势面理论,采用优势指标法将敏感优势层分为3级,并确定了苏通大桥地基中的1粉砂层和7粉细砂层为敏感优势层。苏通大桥采用超长灌注桩基础,桩身全部置于土层中,敏感优势层的工程地质问题主要包括桩基承载力问题、软土流变问题及砂土液化问题。本文研究认为,敏感优势层将导致桩基承载力的降低,敏感优势层的流变将影响基坑的稳定性,通过试验得到了土的流变模型参数。此外,敏感优势层皆为砂土层,在震动荷载作用下会发生液化而丧失承载力。更多还原

【Abstract】 Based on the preferred plane theory, the sensitive preferred stratum is classified into 3 grades, from which the stratum of fine silt-1 and silt—fine-sand-7 in the foundation of Suzhou—Nantong (Sutong) bridge are verified to be the sensitive preferred stratums. To Suzhou—Nantong bridge, the super long piles will be used, and the body of the piles will be all in the soils. So the engineering geology problems of the sensitive preferred stratum include: bearing capacity of the piles, rheology of the soft soil and sand liquefication. The study resumts indicate that because of the sensitive preferred stratum, the bearing capacity of piles will be reduced, the rheology of the soft soil will affect the stability of the pits, by the experiments the parameters of the rheology model are gotten. Under the effect of the quaky loads, the sands is easy to be liqueficated, then the stratums will lose bearing capacity.更多还原