土压力盒(这里涉及的是边界式)是目前进行土压力实测的基本工具。国内常用的以钢弦式压力盒为多,都是单膜挠曲式的。单膜结构的土压力盒与土介质直接接触的感压膜片产生弹性挠曲变形。由于起拱效应,土介质的反力状态依膜片挠曲变形程度的不同而发生不同的变化;整个膜片变形的性状 The earth pressure box (in this case, the boundary type) is the basic tool for earth pressure measurement. Domestic steel wire pressure boxes are commonly used, and are all single-film flexure type. The pressure-sensitive diaphragm that is in direct contact with the soil medium with the single-membrane structure of the earth pressure box produces elastic deflection deformation. Due to the arching effect, the reaction state of the soil medium varies according to the degree of flexural deformation of the diaphragm; the deformation of the entire diaphragm occurs.