DEVELOPMENT AND APPLICATION OF SIMULATION SYSTEM FOR MODEL PILES IMPACTED BY SOIL TRIAXIAL LOADING AND UNLOADING
YANG Min1，2，LI Dening1，2，LOU Xiaoming1，2
(1. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education，Tongji University，Shanghai 200092，China；2. Department of Geotechnical Engineering，Tongji University，Shanghai 200092，China)
Abstract：A simulation system is developed to investigate the changes in skin friction of piles due to the triaxial loading and unloading of soil. The system consists of four subsystems：triaxial loading and unloading system，model piles，measuring system and automatic data acquisition system. The system can get higher pressure with the help of pneumatic loading method；so that the impact of soil compression and rebound on model piles under different soil properties and end restraint conditions is simulated. The validity of the apparatus is verified by elementary tests. The test results show that the system with high intelligence can achieve long-term constant load. The maximum value of positive and negative skin friction for the bottom free piles increased with the increase of applied triaxial load. The neutral point lies in the region from 0.5L to 0.6L. At the beginning period of unloading small rebound deformation of the soil happened；but the tension of the pile caused by the rebound has developed rapidly to a larger value. The system can be used to simulate the effect of the soil loading and unloading on piles under different strss paths.
杨 敏1，2，李德宁1，2，楼晓明1，2. 土体三轴加卸荷对桩基影响模型试验系统研制与应用[J]. 岩石力学与工程学报, 2013, 32(2): 411-416.
YANG Min1，2，LI Dening1，2，LOU Xiaoming1，2. DEVELOPMENT AND APPLICATION OF SIMULATION SYSTEM FOR MODEL PILES IMPACTED BY SOIL TRIAXIAL LOADING AND UNLOADING. , 2013, 32(2): 411-416.
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2013, Vol. 32 
