关键词: 沉桩侧向挤土效应, 有限元法, 应力路径三轴试验, 荷载传递法, 承载力

Abstract: The squeezing effect can be caused by the construction of jacked piles. The behavior of soils surrounding a jacked pile is changed; and it has an influence on the load bearing capacity of the pile. The jacked-in process of a single pile is simulated by FEM. The displacement and stress of the soils surrounding the pile are calculated. In addition, stress path controlled triaxial tests were carried out to simulate the stress state of the soils after the construction of a jacked pile; and the mechanical characteristics of standard sand under subsequent loading were studied. Furthermore load transfer method based on finite difference calculation is used to predict the load-settlement curve of single pile with and without consideration of the squeezing effect. It is shown that the axial and radial stresses both are affected significantly; and the radial effect is more obvious than the axial effect. The shear modulus and strength of the soil surrounding the pile increase; and the influence zone is essentially the same. The load bearing capacity of a single jacked pile increases in consideration of lateral squeezing effect. The design method of jacked piles is conservative.

Key words: lateral squeezing effect of a jacked pile, finite element method, stress path controlled triaxial test, load transfer method, load bearing capacity