stream lining
2.Complicated hydrologic and geographic conditions,and the large scale of the Xiaolangdi Hydraulic Project on the Yellow River are introduced briefly.Three desilting tunnels are designed to meet the requirements of flood control,sediment discharge and runoff regulation.According to the performance requirements of desilting tunnels,the tunnel lining down-stream of the grouting curtain is designed to be post-tensional prestressed lining.On the basis of investigation and research,experiements and analysis,the unbonded prestressing system is used.It is the largest unbonded prestressed tunnel lining project in the world,and the first one in China.

