动探击数N_(63.5)作为砂砾石液化判别和工程检测标准的研究

Study on the N_(63.5) by CPT as Judge Method for Sand-gravel Layer Liquefaction and Criterion for Foundation Detection

饱和砂砾石层存在地震液化的可能,但其地震液化判别,目前尚缺乏有效可靠的检测方法和判别标准。通过砂砾石层重型动力触探击数N63.5和相对密度Dr对应关系的试验,探索和研究了采用重型动力触探方法测试水下砂砾石层的密实度,进行地震液化判别的可行性;试验结果表明,采用重型动力触探方法进行检测和判别是合适的,并已成功应用于坝基砂砾石层工程处理后的检测标准。

The saturated sand-gravel layer may be liquified while earthquake happens, but now no any methods and criteria are available and effective to detect and judge the liquefaction of saturated sand and gravel. On the basis of test and study on the relation between N63.5 by CPT and relative density Dr ,the authors discuss the feasibility that N63.5 by CPT is used to measure density, and further discriminate the liquefaction of underwater sand-gravel layer. The test results show CPT is reasonable to detect and judge the liquefaction of saturated sand-gravel layer. And as a detection criterion, it has been applied successfully in inspecting sand-gravel layer of dam foundation after treatment.