The Reaserch And Application Of Stress-strain Relationshipe Of Concrete Confined With Steel Wire Mesh Under Axial Compression

Steel wire mesh and polymer mortar reinforcement method is a new reinforcement technology was invented in recent years,and has been gradually used in engineerings.Compared with traditional reinforcement methods,this method has the advantages of good fire resistance,good durability,convenient construction as well as wide application range and has a bright future.The research of stress-strain relationship of concrete confined with steel wire mesh is the foundation of other mechanical properties of concrete reinforced with steel wire mesh and is necessary,besides,the research in this field is lack at home and abroad.Several typical models including srtess,srtain and stress-strain relationship for confined concrete are listed,and the models of sertss,srtain for peak point are compared according to collected experimental members.The factors that influence the axial compressive behavior of concrete column strengthened with steel wire mesh are analyzed.In this paper,based on Hoke-Brown failure criterion and the theory of actively confined concrete,a theoretical model is developed to calculate the peak stress of concrete columns confined by steel strands;The relationship between lateral strain and longitudinal strain is analyzed according to the relevant actively confined concrete experiments,and then combined with Ottosen stress-strain relationship of concrete and the generalized Hooke's law,the analysis model of stress-strain relationship of steel wire mesh-confined concrete columns is established;and a program is written and used to calculate the sertss,the srtain for peak point and the stress-strain relationship of collected experimental members,the calculated results agree well with the experimental ones.In this paper,the calculation process of the stress-strain relationship model of steel wire mesh confined concrete column is also applied to the calculation of the stress-strain relationship of prestressed steel strip confined concrete columns,demonstrating this model has wide applicability and expansibility.In addition,the stress-strain relationship design model of steel wire mesh-confined concrete columns is established by regression analysis of the collected experimental members with differentsections,different concrete strength and different spacing of steel wire.The stress-strain relationship model is applied to study the mechanical properties of steel wire mesh and polymer mortar reinforced concrete column under low cyclic loading and under eccentric compression loading.The skeleton curves of strengthening members under low cyclic loading and the ultimate bearing capacity of strengthening members under ccentric compression loading are calculated through computer programs based on deformation campatibility,force balance and strip methods,the calculated results agree well with the experimental ones,which verifie the stress-strain relationship of steel wire mesh-confined concrete columns established in this article is practicability and validity.