Study on the mechanical behavior of loess arch and soil arching effect area

The loess arch is the important bearing substructure for the loess cave dwelling. In order to study the mechanical behaviors of the loess arch, four models with different thickness of covering soil were tested under vertical static load. The failure patterns, bearing capacity, deformation, distribution of soil pressure and soil arching effect were analyzed. Based on the experimental study, the finite element model of loess arch was established. The calculation results and the test results agreed well, and the soil arching effect area of loess arch was discussed. The results showed that the loess arch experienced elastic stage, elastoplastic stage and failure stage during the loading process. The bearing capacity of loess arch increased as the increasing of thickness of covering soil. The ultimate vertical displacement of arch crown was larger than 10mm, far greater than the corresponding limit value of the loess cave dwelling. At the same height, the distribution of vertical soil pressure was V-shaped in the proportional limit point, except the arch foot plane. Above the arch crown, the closer to the arch crown, the more significant the soil arching effect was. Finally, the function of boundary line of the soil arching effect area was determined.