Research On Mechanical Performance Of Corrugated Steel Strengthened Reinforced Concrete Slab Culvert

Corrugated steel reinforcement technology has a wide application prospect in Culvert Reinforcement because the bearing capacity of culvert can be greatly improved,the road traffic condition will not be interrupted during construction,and the construction is green and convenient.In recent years,the theoretical research on the reinforcement of culvert with corrugated steel plate has been carried out.There are few researches on the mechanical properties of slab culvert strengthened with corrugated steel plate.The analysis of parameters affecting the reinforcement effect of slab culvert is insufficient.The numerical simulation accuracy of corrugated steel plate reinforcement is not high,and the construction guidance of reinforcement culvert is insufficient.A more comprehensive and systematic understanding of reinforcement mechanism and reinforcement design method and construction method have not yet been formed.Therefore,in this paper,the mechanical properties of reinforced concrete slab culvert strengthened with corrugated steel tube are tested in laboratory and simulated by finite element method.Firstly,the reinforcement effect,failure mode,deformation and stress characteristics and failure mechanism of the reinforcement system are analyzed through the mid span single point loading test;secondly,the simulation model is established by using the finite element software ANSYS,and the accuracy of the finite element model is verified through the comparative analysis of the finite element numerical simulation and the field test results;and then,the analysis is carried out on the basis of the finite element model Finally,this paper summarizes the key construction technology of corrugated steel reinforcement.The main conclusions are as follows:(1)The results show that the ultimate bearing capacity of the strengthened slab system is increased by 5.66 times,and the mid span displacement is reduced by 29.81%.The bearing capacity of the existing slab culvert strengthened with corrugated steel can be greatly improved;before and after reinforcement,the failure mode of the culvert system changes from mid span bending failure to shear failure;when the corrugated steel semi-circular arch lining is used to strengthen the slab,the deformation of the corrugated steel semi-circular arch and the side walls on both sides is small;The reinforcement system is mainly controlled by the shear strength of simply supported slab and filled concrete before failure,and by the bending strength of corrugated steel arch after failure.(2)The equivalent method of filling layer concrete with equal minimum strain potential energy and the equivalent method of side wall and bottom slab concrete with equal section flexural stiffness are proposed.(3)The bearing capacity of the slab culvert strengthened with corrugated steel mainly depends on the strength of the inner filler,the thickness of the corrugated steel plate,the wave shape size and the thickness of the existing slab,while the influence of the reinforcement ratio of the existing slab is small and can be ignored.The steel corrugated plate structure has good mechanical properties,high strength and good ductility,which is suitable for complex foundation.When it is used for reinforcement,the original culvert foundation can be directly used without special treatment.Using corrugated steel plate to reinforce the original culvert can reduce the investment,is conducive to environmental protection,has good economy and broad application prospects.