强夯加固曹妃甸吹填地基振动影响范围的模型试验研究

结合曹妃甸工业区强夯产生振动破坏的工程实践,自主研发强夯振动监测的大型模型试验台,通过两个方面确定强夯振动影响范围:首先,对强夯产生的振动加速度时程进行研究分析,得到水平加速度在吹填地基中的衰减规律及衰减计算公式,根据振动加速度小于0.1g时,建筑物基本是安全的,确定曹妃甸地区不同夯击能下的振动影响范围;其次,根据实测CFG群桩模型中单桩的受力情况,拟合得到桩身最大拉应力与夯击能和距夯点距离的关系式,进而根据混凝土的极限拉应力确定强夯振动影响范围。

MODEL TEST STUDY ON VIBRATION INFLUENCE RANGE OF DYNAMIC COMPACTION OF CAOFEIDIAN DREDGER FILL FOUNDATION

Combined with the engineering practice that dynamic compaction produced vibration destruction in Caofeidian Industrial Zone,the large model test of dynamic compaction vibration was researched and developed independently.Through two aspects tamper vibration influence scope was determined: first,the vibration acceleration time history was researched and analysed,the decay laws and attenuation formula of horizontal acceleration in dredger fill foundation were deduced.Based on the fact that the building would be safe when vibration acceleration was less than 0.1g,the vibration influence ranges of Caofeidian Region with different ramming energy were determined;second,according to the stress distribution of single pile in CFG piles model,the formula of pile body maximum tension stress of the pile with ramming energy and distance to tamping point was fitted,then according to the ultimate tensile stress of concrete the tamper vibration influence scope was determined.