Discussion On A Test Method Of CFG Pile And PHC Pipe Piles Of Composite Foundation Static Load

I Department of Engineering quality inspection staff of Qingdao Construction Quality Inspection Center Co., Ltd., the main tasks for the engineering quality testing based on building foundations, including the construction of pile and composite foundation static load test, low strain detection, high strain detection, acoustic transmission method, drill core assay, anchor pullout testing. In this paper, according to my department in 2013 8 to 10 months for a construction project in Chengyang District of composite foundation static load test of experience, the test data obtained to sort out the analysis, under the guidance of instructors refer to the corresponding literature, etc., to test the conclusions summarized, and include some personal understanding and ideas, as well as on the use of standardized test methods, to be analyzed together.This project is located in Qingdao Chengyang Xifu town resident, are designed to be planning to build high-rise buildings within the area, the height of 22 to 24 layers, the original design basis requires CFG pile composite foundation, were carried out in pre-construction test pile bearing force test, can meet the design requirements. After construction is completed pile of CFG pile every single project will be vertical compression static load acceptance test, but also can meet the design requirements, but by the CFG pile composite foundation formed by the composite foundation static load test is conducted Test results have failed to meet the design requirements. By analyzing many reasons, decided to re-original composite foundation reinforcement, taking into account the conduct of foundation reinforcement schedule again, the owner, design and other research decision on the project to make additions PHC piles, pile construction is completed after the meeting again by the PHC Multi-pile and CFG pile composite foundation piles were composed of static load test, the test results can meet the design requirements.Due to the addition of the pile with the original type of pile of different type, resulting in a base form the foundation of the great changes occur. First, the basic form of composite foundation pile into a multi-pile composite foundation, followed by the two forms into a different rigidity composite foundation pile. This multi-pile composite foundation static load test in the current rules for the operation corresponding detection specification is almost not involved, and the corresponding design currently in the country is also rare, so I feel that this form of Composite Foundation of static load test methods and test processes are discussed, it is necessary, which may have a very important practical significance.Through this multi-pile composite foundation static load test, the more accurate this project has been more than pile composite foundation bearing capacity of foundation engineering inspection provides a very important reference, the successful solution of the pile when the composite foundation static load test does not arise, and proves two different stiffness composite foundation pile type composition of the static load test, by adjusting the load center of gravity position, you can make just settlement of displacement on both sides of a substantially flexible piles balance, this adjustment method is feasible on engineering testing and necessary, the test is to provide a reference for other similar projects; from a larger sense, this article may be similar engineering problems for the country concerned to develop appropriate standards and regulations to provide a case.