Study On The Engineering Geological Condition Of Erguang Expressway Yongzhou To Lanshan

The Erguang Expressway is the sixth vertical trunk in the national expresswaynetwork，and an important part of five vertical and seven horizontal trunk in HunanProvince expressway network. The Yongzhou to Lanshan section of ErguangExpressway palys an important role in promoting of economic development of Hunan.Currently， the construction of the Yongzhou to Lanshan section of ErguangExpressway has entered the Engineering feasibility study stage. At this stage，thestudy on the engineering geological conditions is the governing factors of the finalplan. Therefore，the study on engineering geology not only benefits to determine theroute scheme corridor scientifically and reasonably， decrease the difficulty ofimplementing Erguang Expressway， but also play a decisive role in the project costcontrol and the assurance of the construction progress of Erguang Expressway.Based on our previous studies，combined with actual investigation and entirelyresearch of engineering geological condition and engineering geological problems ofthe route plan，we made a comparison between each routh plan is made. Aiming at theselected scheme,the unfavorable and potential engineering geological problems areanalyzes, and some preventing and processing measure are proposed. Are proposed.Conclusions are as follows.(1)Four area landform genesis: Erosion and tectonic geomorphology, Tectonicdenudation landform, Dissolution of karst landform, Erosion accumulation landform.Divided fourteen Genetic subtype: Granite middle mountains, epimetamorphic sandyslate middle mountains, epimetamorphic rock, sandstone low mountain, Hilly ridgeValley, low hills, Low hilly gully, red rock hill,(2) The location and type of the unfavorable geologic bodies.the unfavorablegeologic bodies mainly include collapse, landslide, mud-rock flow, karst..The SpecialGeologic bodies mainly include soft soil and weak expansive soil.(3) According to the forming condition, type, structural features and so on, therock and soil mass in the region could be divided into eight engineering geologicalpetrofabrics, Which are hard granite rock group, hard and semi-hard clastic rock group, hard carbonate rock group, hard and semi-hard carbonate rock clip clastic rockgroup, hard and semi-hard epimetamorphic rock group, semi-hard and soft clasticrock group, soft clay, sand and gravel rock group, soft gravel rock group respectively.(4) According to the detailed analysis and evaluations on the geologicalconditions of the route and28structures, the results suggested that the majorgeological conditions were poor, complex, and difficult to construct..(5) Taking geomorphology, geology, engineering geology, hydrogeology, andunfavorable geology into account, the optimal plan K after a comparison of the routeplan including plan K, plan A+K, plan B+K, plan C+K is got.(6) According to the special geological categories and features of differentunfavorable geologies, and the possible geological disasters caused by construction,the corresponding engineering preventive measures and suggestions are proposed.