Abstract：In order to solve engineering problems of high groundwater level or unable to reduce the groundwater level due to site restriction and some other special reasons, the author used the U-shaped structure to connect the underground tunnel with the ground subgrade. Based on the geological conditions and hydrogeological characteristics in the study area, and combined with domestic engineering examples, the author determined the U-shaped structure cross-section and calculation model of side wall and bottom board. Then the force and reinforcement were analyzed and calculated, the crack width and anti-floating stability were checked, and foundation pit enclosure and groundwater controlling measurements were selected. Cantilever beam was selected as the calculating model, and bottom board was selected as the elastic foundation beam. The reinforcements were calculated with the most unfavorable load combination. Meanwhile, the groundwater was controlled by tube well precipitation and waterproof curtain. The calculated and checked results could satisfy the design requirements, and engineering measurements are reasonable. This research could provide some reference and instruction for similar engineering design.
2018, Vol. 5 
