含水层顶板 meaning in English

aquifer roof

( 5 ) the author researches the relationship between the deep foundation ' s shape , area and depth and the deep excavation dewatering . the formula , which calculates the minimum distance between foundation ' s bottom panel and the confined water layer ' s top panel , was put forward
(五)研究了基坑形状、面积、深度与深基坑降水相关性，给出了计算基坑底板至承压含水层顶板间的最小距离公式，分析了针对不同基坑应采用的降水方法。