2005•Journal of Highway and Transportation Research and DevelopmentRequires access
The Comprehensive Evaluation on Roof Stability of Karst Cave Under Bridge Foundation
Ren Wang
Open publisher page 1 citations
Abstract
Based on qualitative analysis of engineering geology of karst cave-surrounding rock under bridge foundation,with the action of gravity and pile foundation loading,the roof stability of karst cave was comprehensive evaluated with the method of structural mechanics and 3-D finite-element method.The responses of stress and displacement of different thickness karst cave-roof were analyzed,the roof of karst cave is stable if the pile embedded on the stable rock formation,and the thickness of karst cave roof can't less than 8.0m.Considering the effect of blasting vibration when foundation ditch of 4 # pier was excavated,8.5m safety thickness of karst cave roof was determined.And the multiple-point borehole extensometer was inbuilted in Karst rock,so deformation of Karst cave and cave roof rock mass were monitored in-site.The tested results monitoring show that 8.0m thickness of karst cave roof which break through conventional design is safe.It would reduce investment outlay of treating Karst cave,and it supply technic guide for similar stability analysis of Karst cave roof.