CAJ | 학술논문

利用固定网格法分析三维非稳定渗流问题时，将要面对两项积分难题：以自由面及单元表面为边界的空间积分及以自由面为边界的曲面积分。针对常用的任意8结点6平面三维普通单元，提出采用坐标变换及等参变换技术求取空间积分项的精确数值解；至于曲面积分项，建议改用单元非饱和区部分表面作为积分边界，经过坐标变换及等参变换处理积分边界后，利用高斯数值积分可求出曲面积分项的精确数值解。通过一个普通单元及一项均质半无限边界堤坝的实例分析，表明此方法的精确性和稳定性良好。
이용고정망격법분석삼유비은정삼류문제시，장요면대량항적분난제：이자유면급단원표면위변계적공간적분급이자유면위변계적곡면적분。침대상용적임의8결점6평면삼유보통단원，제출채용좌표변환급등삼변환기술구취공간적분항적정학수치해；지우곡면적분항，건의개용단원비포화구부분표면작위적분변계，경과좌표변환급등삼변환처리적분변계후，이용고사수치적분가구출곡면적분항적정학수치해。통과일개보통단원급일항균질반무한변계제패적실례분석，표명차방법적정학성화은정성량호。
When using the fixed mesh method in analysis of 3D unsteady seepage problem ,one will face 2 difficult integral problems :the spacial integral with free surface and the element surface as the boundary and the curve surface integral with free surface as the boundary .Against the common and randomly used three‐dimensional 8‐nodes 6‐planes ordinary element ,it is proposed that an exact numerical solution of space integral can be obtained by using the technology of coordinate and isoparametric transformations . With regard to the curve surface integral ,it suggested to switch using that part of element surface in unsaturated zone as the integral boundary ,and then through working for the integral boundary with the coordinate and isoparametric transformations ,an exact numerical solution to the curve surface integral can be obtained by using Gaussian numerical integration .The analysis of a common element and a practi‐cal example of a dam under a homogeneous semi‐infinite boundary can illustrate a rather good accuracy and stability of this method .