| Funded by the National scientific discipline Foundation of China project "Design theory and intelligent construction methodology of ready-made hybrid structure bridges in mountainous areas"(U20A20312),so as to grant full play to the ready-made construction blessings of steel-concrete composite structure bridges,this thesis implifies the upper deck structure and therefore the construction technology improves the service lifetime of the bridge,and proposes a brand new kind of steel-concrete composite bridge consisting of "steel beam + key tooth rubber joint + high-strength bolt + ready-made concrete slab".Since the mechanical performance,force mechanism and failure mode of the structure within the negative bending moment space don’t seem to be nonetheless clear,associate experimental study of 2 absolutely assembled composite beams below negative bending moment was dole out.in step with the characteristics of the force,a prestressing methodology while not post-tensioning is planned to explore the protection and practicability of the structure below negative bending moment,and supply a reference theme for the speedy construction of bridges,the development of inexperienced traffic and therefore the manufacture of bridges.the most analysis work is as follows:(1)Two items of absolutely assembled steel-concrete composite beams were designed,that were the integral bridge and therefore the pasted plate bridge,and therefore the negative moment single-point loading bending check was allotted to match and analyze the plasticity,stiffness,and bearing capability of the 2 beams.Ability and different mechanical properties.Compared with the general absolutely assembled sort,the bearing capability of the absolutely assembled steel-concrete composite beam with secure plates is reduced by Martinmas,however the plasticity may be accumulated by one.11 times;the rotation capability of the lower section of the secure plate sort is one.3 times that of the integral sort.it’s a lot of contributive to the deformation and earthquake resistance of the structure;additionally,the cracking load of the absolutely assembled steel-concrete composite beam with pasted plates is one.33 times over that of the general absolutely assembled.(2)A refined numerical model of the absolutely assembled steel-concrete composite take a look at beam was established,and also the foregone conclusion of the model was verified by examination the analysis results and take a look at results of the megascopic constitutional structure,failure mode and concrete block injury.supported the numerical model,the net stress transfer of absolutely assembled composite girders,the strain method of every member and also the influence of external prestressing area unit analyzed,and also the force mechanism of absolutely assembled bridge decks secured with key teeth within the negative moment zone is disclosed.(3)Based on the take a look at results and numerical analysis,a abstraction beam lattice model of absolutely assembled composite beams with pasted joints and high-strength bolts was established,and a construction methodology of pin jacking to force steel beams to deform and apply preload was projected and simulated.On the premise of substantiating the dependability of the abstraction beam-lattice model,the practicability of the appliance of fully-assembled composite beams with glue-bonded plates in medium-and small-span continuous beam bridges is mentioned.Taking the 3×60 m composite beam steel bridge with assembled chemical characters as associate example,the house beam model of the continual composite beam bridge with pasted plate absolutely assembled and cluster nail cluster assembled is severally established,and therefore the distinction in mechanical performance between the 2 is compared,and therefore the Influence of assembly order of bridge on prestressing result throughout pin jacking. |
