液压高频振动沉桩的饱和土超静孔压及单桩静载特性试验研究  

Experimental studies on pore pressure of saturated soils and bearing capacity of piles driven by high-frequency hydraulic vibrator

作　　者：邓俊杰[1] 陈龙珠[1] 邢爱国[1] 宋春雨[1] 

机构地区：[1]上海交通大学船建学院安全与防灾工程研究所,上海200240

出　　处：《岩土工程学报》2011年第2期203-208,共6页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(50779034);上海市重点学科(B208)

摘　　要：为解决常规锤击、电动中低频振动法进行桩基施工时引起较为严重的噪声、振动和增大电网负荷等问题,发达国家已在应用液压高频振动施工技术,但沉桩的土动力学机理以及单桩静力荷载–沉降特性等尚缺乏深入的室内外试验研究。利用大吨位液压高频振动锤,在某深厚饱和软土场地对直径500 mm、长度26～29 m的预应力管桩进行了沉桩施工试验,观测了邻近地基土超静孔压随沉桩深度而上升及其后续消散的过程;在休止期满后进行了单桩竖向静载荷试验,并将实测极限承载力与其它常规施工方法的进行了比较分析。试验结果对推广应用液压高频振动沉桩新技术,具有重要的学术和应用参考价值。To solve the serious noise and vibration problems as well as the high pressure on the capacity of city power supply caused by the existing piling methods with falling hammers and low-frequency electric vibrators,a new piling technique using high-frequency hydraulic vibrators has been used in some developed european countries and the USA.The piling mechanism related to soil dynamics at high frequency and the bearing capacity of piles after installation with the hydraulic vibrators should be investigated in laboratory and construction sites.Using a high-frequency hydraulic vibrator manufactured by a Shanghai machinery company,pre-casted/pre-stressed concrete pipe piles with diameter of 500 mm and length of 26~29 m are driven into the saturated soft ground in the Minhang campus of Shanghai Jiaotong University in China,and the induced excess pore water pressures of adjacent soil at different depths are investigated for about one month.After the specified interruption period of 28 days after piling,the ultimate bearing capacity of each pile is studied by means of the conventional static loading tests and compared with that of piles installed with falling hammers and statically jetting.The experimental results can be a useful reference to the application of high-frequency hydraulic vibrators to piling in practice.

关 键 词：饱和地基 预制桩施工 液压高频振动锤 超静孔隙水压力 单桩静载荷试验 

分 类 号：TU473.1[建筑科学—结构工程]