lead-in chamfer dimension

It gains the sedimentation of deep alluvium by the laws of sedimentation, and determines the size of stress relief slot.

深厚表土层冻结双层井壁因表土失水沉降,井壁纵向压缩破坏,等强修复井壁,按沉降规律计算最终表土层沉降值选择卸压槽尺寸。