The Survey Of Flood Damage And Genetic Study On Bridge And Culvert Of High-gride Highway In Qinba Mountain Area

There is usually the flood damage occurred on bridge and culvert of the high-grade highway in Qinba mountain area every year along the route, this serious influence highway traffic normal operation. In order to sharpen the anti-flood damage ability of bridge and culvert of high-grade highway in mountainous area, has the necessity to carry on the careful investigation very much in view of the bridge and culvert flood damaged condition, analyzes the bridge and culvert flood damaged mechanism, studies its prevention countermeasure.Through the scene observation on the terrain landform and the hydrogeological conditions along the route of Qinba mountain area, combining the system collection for all previous years flood material, the river bed material and the original engineering design material's, to carry on the careful investigation and reorganize about the flood damaged phenomenon on the high-grade highway along the route, statistic the bridge and culvert flood damaged proportion in local and study on the main flood damage influencing factor each local, thus summarized the chief feature, the predominant type and the primary cause which affects the bridge and culvert flood damaged.Obtains from analysis the destruction form when flood torrent the bridge, according to the climate and the terrain environment characteristic of Qinba mountain area, has studied the bridge damaged genetic by flood torrent function, when, the river channel choking, the landslide and debris flow impacting, the flood carry the floating matter hitting, the silt up and stacking etc.;According to the stress analysis of bridge when the flood shock effect's, combining the hydraulic, the hydrology knowledge, derived the conversion relation among the velocity of flow before bridge'v', the pulsation speed of flow'v′'and the time-averaged speed of flow'v'in the conversion relations comparatively perfect condition; Through example contrastive analysis the bridge is issubjected mountain torrent force when the speed of flow is invariable and the change tendency of speed of the mountain torrent various actions' when action and flow change in typical road section of Ankang, Hanzhong and Shangluo area, obtains the main flood damaged origin from this when flash flood each local.By means the mechanism research of bridge local scour and the abutment washout's, analysis and summarize the flood damaged origin of bridge souring effect under the mountainous area; Unifies the scene gauging data and collects the material, carries on the example analysis using the bridge pier local scour correlation formula to the bridge which water scouring typical road section. In addition, unifies present standard and existing research results, based on the design principle of "first prevention, prevention and treatment integrated" for flood damaged prevent, in view of the concrete characteristic of road section's where flood damaged in the high-grade highway of Qinba mountain area, propose the countermeasure of bridge and culvert flood damaged from the design construction and maintenance management two aspects.