Research And Application On The Estimation Of Sinking-pile Resistance By The Data Derived From Situ Testing Of Soft Soil In Tianjin Area

For the flourishing development of the construction market, managers payattention to green environmental protection more and more. Hydraulic static piledriver technology has many advantages compared to some other construction methods,such as less noise and disturbance, high efficiency, cutting down cost and reducingpollution. For all those reasons, hydraulic static pile driver technology has beenwidely applied. Before pile foundation construction, estimating of sinking-pileresistance accurately is very important, which will decide the selection of pile typeand construction equipment.On the researching of others, this paper makes full use of the data in situ testing,and tries to estimate the sinking-pile resistance using the gain of static conepenetration test and standard penetration test. The research mainly includes thefollowing contents:1. Based the analysis of the static cone penetration test and static driving pilesconstruction; purpose and significations of the research are introduced. Following, theresearch method, technical route and achievements are provided.2. After summary of the development of the static cone penetration test, researchstatus and theory of mechanism of penetration are provided.3. Development of static driving piles construction is introduced. Followed thecharacters and the influencing factors of the construction method are analyzed.4. Based the analysis of existing empirical formula of sinking-pile resistance, thispaper provides a formula which derived from the data of double bridge conepenetration test. Also, the depth bounds which influence the pile tip resistance areobtained based on the differences research between the cone penetration test and thestatic driving piles construction. Through comparison with the practice construction,the formula is revised by both of the correction factor of tip resistance and sidefriction of pile. Besides, on analysis of data from multiple static driving pilesconstruction sites in Tianjin soft soil area, this paper study the relationship betweenthe data obtained by standard penetration test and static cone penetration test. Thenempirical coefficients are provided.5. According to the revised formula of sinking-pile resistance, software ofestimating sinking pile resistance is created. Then the software is applied to practice.Compared to the actual data obtained by construction, the calculated values areacceptable. That proves the formula to some extent.