Study On The Constitutive Relation Equivalent Method And Model Test Of Composite Main Arch Circle

Masonry arch bridge is widely used in our country because it has graceful shape, easilyobtained, bearing potential and so on. But with the volume of traffic grow significant, thetraffic density and vehicle load growing, a considerable part of existing masonry arch bridgehas failed to meet the requirements. This stage the reinforcement of masonry arch bridgebecomes an important topic in the field of study on arch bridge. Main arch circle is theprimary load-bearing structure of arch bridge, and it is also the focus of reinforcement. Thetechnology of composite main arch circle to strengthening masonry arch bridge is morewidely used in our country because of its easy construction and low cost.Composite main arch circle increase the concrete size of component surface, add thestressed steel bar, to form an overall with the original structure, then increasing the effectiveheight and reinforced area of component, increasing the stiffness and improving the bearingcapacity. In this paper, two kinds of materials, masonry and concrete, in accordance with theunified theory, deduced a unified constitutive relation of composite materials. And based onfour different concrete material models, calculating its unified constitutive relation. In orderto study the mechanical properties and validation on unified constitutive relation ofcomposite main arch circle, this paper designed and made four components named A, B, C, D,with different width of reinforcement layer. A model experiment carried out on200Tonsuniversal presses, and collected the datas of strain and deflection. At the same time, using thelarge finite element program ANSYS based on the unified constitutive relation which hadbeen deduced to analyse and contrast each component.By the comparison of carrying capacity, failure pattern, stress-strain curve and measuredconstitutive relation, we found that composite main arch circle greatly increased the capacityof original structure. And the unified constitutive relation which based on Rusch Model isclosest to actual situation, and the formula is safe, can play a reference role in engineeringpractice.