The Analysis Of Temperature Effect And Experimental Research On Collapsible Loess Of Wangpogou Bridge

In recent years, concrete filled steel tubular Arch Bridge has achieved rapiddevelopment owing to lightly and ingeniously structured and beautiful shape andSpanning capacity and convenient construction. However，the theory research of TheCFST is Lagging behind the engineering practice，There is no uniform the designtheoretical basis and unified design specifications，which had seriously restricted thehealthy development of CFST. We are late learned to the temperature field in CFST andThere is no a unified specification for the temperature evaluation。Therefore, it isnecessary to conduct an in-depth study about the Temperature Effects of the CFST ArchBridge.In this paper, the Wang Po Gou concrete-filled steel tube arch bridge as a practicalengineering background, to study the arch rib temperature field test and Collapsibilitytest of loess, the following are the main conclusions of this paper:In terms of temperature, first of all, it makes basal and theoretical analysis for theheat transfer mechanism of steel tube concrete arch rib under the sunshine, then usingthe Galerkin method to make a formula derivation about Two-dimensional transientwithout inner heat source temperature field of Concrete filled steel tube arch rib, whichlay the theoretical foundation for Calculation analysis of temperature field.Simplify the boundary conditions of sunshine temperature about the concrete-filled steeltube arch rib section by divided Dumbbell shape of arch rib into11circular surface andmake Numerical calculation of thermal boundary conditions of Dumbbell shape of archrib, which conducting a plane transient temperature field analysis of ANSYSsoftware.Through dumbbell shaped arch rib section temperature testing and dataarrangement under the action of the sunshine, the characteristics of the arch rib sectiontemperature field is studied, on this basis, Arch rib concrete filled steel tube arch bridgeis discussed temperature gradient mode along cross section diameter direction.Thispaper discusses and analyzes the temperature distributions of rizhao effect by simplifythe three-dimensional temperature field as two-dimensional temperature field in rizhaoboundary conditions on the basis of Temperature field simulation analysis usingANSYS software,it is feasible for Temperature distribution of the arch rib sectiontemperature field by comparing with the measured temperature data. Finally, making finite element analysis of temperature difference effect of arch bridge, with the concretefilled steel tube arch rib section and arch bridge under the action of sunlight, whichstudy the distribution characteristics and the influence of dumbbell shaped cross sectionof thermal stress and obtain the influence on arch rib structure.In terms of collapsible loess,through making compression test and direct shear testof undisturbed loess and remodeled-loess to analyze the related influence factors ofdifferent strength characteristics of loess soil for the most economic and reasonablescheme. which is most economic and effective to improving the bearing capacity ofloess, and is good for pile caps and the loess to bear tremendous horizontal thrust at archbridge of pile caps.This paper establish pile caps-pile foundation finite element modelby using Midas/Civil to make a comparative analyzed before and after thereplacement of the loess of adding in lime, the horizontal maximum displacement offoundation pile caps decreased, vertical displacement change decrease, which iseconomically viable to adopting reasonable replacement plaster.