水及土压力的实测研究

DISCUSSION ON WATER AND EARTH PRESSURE OF SUPPORTING STRUCTURE IN SOFT AREA

通过对上海软土地基基坑工程大量的实测土压力、实测孔隙水压力值和实测水位值的分析，阐述了基坑外土压力、孔隙水压力随工况的变化规律。认为软土地区既可采用水土合算，又可采用水土分算。给出了水土合算时的侧压力系数的取值方法；同时提出了水土分算时，土压力与水压力应分别乘以相应的系数，且给出了水压力合理的折减系数ｋｗ值（孔隙水压力与静水压力的比值称为静水压力的折减系数）以及水土分算时的土压力项的侧压力项的系数ｋｓ。

The tendency of active earth stress and pore water stress during excavation is explained through the analysis of measured active earth stress, pore water and water level. In soft area(such as Shanghai), the water pressure and earth pressure can either be calculated separately or mergedly. The method is presented to determine the coefficient of earth pressure when water pressure and earth pressure are calculated mergedly. The earth pressure and water pressure should be multiplied with different coefficients when earth pressure and water pressure are calculated separately) and a method is given to determine the two different coefficients.