CAJ | 학술논문

针对松木桩加固软土地基时软土出现非线性大变形且挤土效应难以精确预测的问题，基于圆孔扩张原理与 FLAC3D 计算程序，提出饱和软土中松木桩挤土效应模拟的快速拉格朗日有限差分法。单桩和群桩挤土效应的数值计算结果表明，该方法是可行的，计算精度明显高于经典的 Vesic 解析法，与模拟桩体贯入土体过程的挤土效应的有限元法相比较，具有实现容易、计算耗时较少且计算容易收敛等优点，克服了有限元法存在的桩土接触面力学参数获取困难、计算耗时大、三维群桩沉桩过程难以模拟等局限性，为软土地基松木桩加固工程的挤土效应合理预测提供了一种有效可行的实用技术手段。
침대송목장가고연토지기시연토출현비선성대변형차제토효응난이정학예측적문제，기우원공확장원리여 FLAC3D 계산정서，제출포화연토중송목장제토효응모의적쾌속랍격랑일유한차분법。단장화군장제토효응적수치계산결과표명，해방법시가행적，계산정도명현고우경전적 Vesic 해석법，여모의장체관입토체과정적제토효응적유한원법상비교，구유실현용역、계산모시교소차계산용역수렴등우점，극복료유한원법존재적장토접촉면역학삼수획취곤난、계산모시대、삼유군장침장과정난이모의등국한성，위연토지기송목장가고공정적제토효응합리예측제공료일충유효가행적실용기술수단。
Nonlinear and prominent deformation of soil will occur and it is very difficult to accurately simulate soil compaction effect when pine piles are used to strengthen soft soil foundation. A fast la-grangian finite difference method based on cavity expansion theory and computer program FLAC3D is proposed to solve these problems. Both numerical results of single pile and grouped piles indicate that this method is rational and much more accurate than the classical analytical solution of Vesic. Compared with the finite element method that simulates the penetration of pile, the fast lagrangian fi-nite difference method has many advantages such as easy realization, less time consuming and fast convergence. The method can also overcome the shortages of the finite element method such as hard-ly obtaining parameters of pile-soil interface, hardly simulating grouped piles with three dimensional model and time-consuming. The proposed method can provide an effective and practical way to esti-mate the soil compaction effect of soft soil foundation strengthened by pine piles reasonably.