The Force Analysis Of The Freezing Cohesive Force On The Water-stop Structure Of The Concrete Slab Dam In The Cold Area

Lianhua Hydropower Station is the largest hydropower station in Heilongjiang Province.The dam is a reinforced concrete face rockfill dam.Due to the cold weather conditions in the north,the water stop structure of the face dam has always suffered damage and destruction caused by the ice body's frost heave thrust,which seriously threatened the safety of people's lives and property.Therefore,it is particularly important to deeply explore the adhesion mechanism and the analysis of the effect of frost heave force,and to propose a reliable optimization design scheme.In this paper,through the finite element theory and technology,the analysis and optimization of the effect of frost heave on the water stop structure can provide an effective reference for researchers to design anti-icing and anti-freezing.According to the above research ideas and purpose significance,the research work and conclusions carried out are as follows:(1)Numerical simulation simulates the frost heaving force of ice coating on the panel under actual working temperature.The stress caused by the expansion deformation is concentrated at the contact interface 1/3 distance from the ice surface,and the maximum principal stress value at the corner is-0.27167 MPa is the compressive stress.(2)Model the rubber water stop cover,flat steel bead and expansion bolt of the typical water stop external components,and analyze the tensile,compression,and shear effects in all directions under the action of frost heave stress.The numerical analysis results indicate: Partial bonding interface separation occurs on the surface of the rubber cover substrate,but the unseparated bonding area is large,which is likely to cause fatigue damage;the flat steel bead almost separates the overall bonding interface,and the effect of frost heave stress is not obvious;under the action of the expansion bolt's frost heave bonding force,there is almost no separation of the bonding interface,which is greatly affected by the shear stress.(3)According to the simulation analysis of the water stop structure,the optimal design is made according to the characteristics of each material component,and the numerical analysis is compared and verified.The optimization scheme is: The new waterstop cover structure with polyurea coating can effectively reduce the bonding area of the bonding interface,release the maximum stress to the limit bonding stress value,and reduce the impact of fatigue factors;replacing the countersunk head bolts can reduce the contact area with the ice body.Significantly reduce the shear stress under frost heave adhesion.Through calculation and comparison before and after optimization,the results show that the original water stop structure has a significant effect after optimization,which can provide a reference for antifreeze design in other similar working conditions.