Development and Treatment of Karst Rock Cavities in Qinduankou in Wuhan
To identify the karst rock cavity development at Xiaoqiao in Qinduankou,the statistical as well as the analytical stud-ies are conducted at Pier 0 and Pier 1,respectively.The results showed that the karst formation at Xiaoqiao,Qinduankou is at the north side of the proposed bridge,which belongs to the L2 bridge zone.The soluble bedrock is the Permian Qixia Forma-tion(P1q)limestone;The probability of encountering karst rock cavities in boreholes is 36.8％,among which 4 boreholes have developed 3-6 karst cavities in a string shaped development,accounting for the 57％of the entire coring length.The maximum linear karst rate is 44.12％,and the karst is therefore strongly developed.The of karst pinnacles are concentrated in the right side the area.The thickness of the karst development zone is 15 meters;Compared with the previously discovered karst devel-opment zone under bridge conditions,the overburden soil thickness in this area is greater,and the embedment depth of the bot-tom plate of the karst cavity below the bedrock surface is mostly 9.80-14.7m;② The quasi embedded karst geological structure is a new geological structure,and the non-soluble bedrock is the carbonaceous shale of the Lower Permian Qixia Formation(P1q).According to the engineering characteristics and geological conditions of the proposed pile foundation,the karst cave was treated by compaction grout.During the construction,the combination of exploration grouting is used to maximize the eco-nomic effect of the geotechnical drilling.
QinduankouKarst Geological StructureKarst CavitiesCombination of Exploration and Grouting
万方数据
维普
