improved zone meaning in Chinese

得到改善的地带

Through the numerical calculation for improved soil layers , there is an economical and reasonable improved zone whose depth is a constant but whose width is decided by the controlling residual deformation of subway structure . and a empirical formula for the subway residual deformation is given which can consider the improvement depth and width
通过对加固后的地基进行多次有效应力模拟，发现南京市地铁地基合理的加固深度基本上保持不变，而合理的加固宽度则可由控制震后残余变形来决定，并给出了计算加固后的地铁隧道震后残余位移经验公式。