地冲击下新型脆断构件防护性能实验研究

To effectively protect the underground structures subjected to ground shock, a new protective component made of foam concrete was proposed. Different from the mechanism of the solid foam concrete layer protection, under the action of ground shock, the proposed components firstly exhibited brittlely fracture, and the fractured parts underwent recontact and compaction, in which the ground shock truncation, load transferred reduction and load form modification on the structures were achieved with the response of the designed components. A field experiment was conducted and the comparison of the dynamic response of the structure (with different protection scenarios, i.e. without protection, with a solid foam concrete layer protection and with the proposed component layer protection) suggested that the superior protective performance was achieved with the fracture, recontact, compaction of the new component. Due to the brittle fracture, the load transfer could be significantly reduced under a relatively low ground shock level, with which the negative protection effect using solid foam concrete layer could be avoided. Subjected to a relatively strong ground shock, the proposed component layer tended to compaction, and its protection effect gradually approached that with the solid foam concrete layer.