Study On The Crack Resistance Of Concrete In The Water Diversion Corridor Of Ship Lock

As an important part of the ship lock structure,the ship lock water conveyance corridor has played an important role in the process of the ship lock water discharge.As a typical large-volume concrete structure,its engineering diseases are caused by temperature cracks during construction and various reasons.In addition to shrinkage cracks,due to its unique concrete service environment,during the period of use,the concrete of the ship lock water conveyance corridor still has the risk of cracking,so it is necessary to study the crack resistance performance of the ship lock water conveyance corridor concrete that has been in service.Based on the Yongning water conservancy project in Nanning,Guangxi,this paper uses theoretical analysis,experimental research and numerical simulation to study the anti-cracking performance of the concrete of the ship lock water conveyance corridor.The influence of basalt fiber of different dosage and length on the mechanical properties and crack resistance of the concrete of the ship lock water conveyance corridor,and the influence of the permeability coefficient of the concrete of the ship lock water conveyance corridor and the flow velocity in the corridor on the concrete cracks of the corridor.The main research contents and methods are as follows:(1)In the theoretical analysis section,by analyzing the service environment of the concrete of the ship lock water conveyance corridor,explore the reasons that may cause the deterioration of the performance of the water conveyance corridor concrete and the potential risk of concrete cracking,and combine this with the concrete According to the type of load,discuss the performance that concrete with excellent crack resistance should have,so as to obtain engineering methods for improving the crack resistance of the concrete of the ship lock channel.(2)In the test part,based on the reinforcing mechanism of fiber to concrete,basalt fiber with different dosage and length is mixed into ordinary concrete to coagulate,and the mechanical property test and crack resistance test of concrete are carried out respectively.The mechanical properties test content is the concrete compressive strength test and splitting tensile strength test.Through the test,the concrete compressive strength,splitting tensile strength,tensile-compressive ratio,tensile cracking strain and tensile toughness are obtained,and the above parameters are used as The mechanical basis of concrete materials with better crack resistance is preferred.The test results show that the basalt fiber concrete with the content of 0.2% and the fiber length of 18 mm has the best crack resistance,which is used as the basis of the concrete material parameters in the numerical simulation work.The anti-cracking performance test adopts the ring restraint method,and the basalt fiber is also used as the research object.The cracking time and crack width of the ring test specimen are used as the basis for evaluating the crack resistance of the concrete.(3)In the numerical simulation part,the ship lock water conveyance corridor model is established,the initial cracks are introduced,the XFEM extended finite element method is used,and the flow parameters of different corridors and concrete materials are explored by adjusting the material parameters and loading schemes.The influence of mechanical properties and different permeability coefficients of concrete on the crack resistance of the ship lock water conveyance corridor concrete.The numerical simulation calculation results show that under each working condition set in this paper,the crack resistance of the fiber concrete optimized by the test is better than that of ordinary concrete;and compared with the magnitude of the water pressure,the cracking of the concrete of the ship lock corridor is in the corridor Water flow velocity is more sensitive;the lower material permeability coefficient of concrete can resist the erosion effect of water flow,and at the same time reduce the permeability of water flow to the initial crack,reduce the risk of hydraulic splitting,and improve the durability of concrete.