Analysis of spatial and temporal stress of waste concrete circular rock

Abstract

Different proportions of waste concrete are mixed into the surrounding rock with crushing agent, and the boundary moisture content, the linear shrinkage rate, the expansion force test, the compaction test, the unlimited compressive strength and the CBR test were verified under different curing times. The surrounding rock stress state has significant spatial-temporal effects. Around the stress evolution process of the surrounding rock in the roadway excavation, the space-time effect of the surrounding rock stress distribution of the circular roadway under the uniform stress field is preliminarily analyzed, and the correlation of time and space and other related parameters is discussed. The study shows that the XiYuan model can fully reflect the stress relaxation effect of surrounding rock, and the three-way stress decreases with time and finally stabilizes in a certain balance state. In the early stage, the more obvious the stress concentration, the stress relaxation; the mechanical relaxation behavior of surrounding rock is a space-time function, the radial stress decreases with the rear distance of the excavation surface, and the annular stress is just opposite, while the axial stress remains unchanged. This study can provide a theoretical basis for the stability prediction and evaluation of rock mass roadway engineering.