钙质砂室内载荷试验研究

Study of plate load test of calcareous sand

为保护和开发海洋资源,在珊瑚礁上进行工程建设时必须要查明岛礁上钙质砂地基的承载力和变形特性。室内载荷试验的结果表明,相同密实度的钙质砂具有比石英砂大得多的承载力和变形模量,变形量则小得多;钙质砂的承载力随着相对密实度的增大而增大,破坏时的变形量显著减小;相同密实度下饱和钙质砂比干燥钙质砂的承载力和变形模量低很多。钙质砂地基中土压力随深度急剧衰减,荷载的有效影响深度为2～3倍基础宽度;随着荷载的增大,土压力从表层逐渐传递到更深的土层。

In order to protect and exploit ocean resources and carry out engineering constructions on coral reefs, it is essential to investigate the bearing capacity and deformation characteristic of calcareous sand on coral reefs. The results of plate load test show that beating capacity and deformation modulus of calcareous sand are much bigger than silica sand, but deformation is much smaller. Beating capacity increases and deformation decreases when failing down with the relative density increasing. Beating capacity and deformation modulus of saturated calcareous sand is much smaller than dry calcareous sand. Soil pressure in calcareous sand ground decays rapidly with depth increasing. Load could spread to 2-3 times breadth of load-plate. Soil pressure spread from superficial to deeper layer with increasing load.