The Mechanics Behavior Research Of Stress-Absorbing Layer Used For Cement Concrete Bridge Deck Pavement

The paper spreads the high elasticity asphaltic sands stress absorption level structure take the cement concrete bridge floor asphalt paving level base as the object of study, uses in the room small experimental and the ABAQUS value simulation method, to spreads around the stress absorption level mechanics behavior to conduct the research, the key attention asphalt paving level interior, the stress absorption level interior and with the bridge floor cement concrete caking contact surface place, uses correctly by it to this structure provides the technical basis and the criterion.Carried on the mixture ratio design and the performance examination regarding the high elasticity asphaltic sands stress absorption level material, uses three kind of gradations to carry on the Marshall mixture ratio design, the cleavage strength experiment, the water stability test, the wheel rut experiment, the beam bend test,and the low temperature breaks roads and so on experiment to use the performance test frozen, the determination optimum gradation.The young Liang bend test and the low temperature break the test result to indicate frozen that, the high elasticity asphaltic sands stress absorption level material has the good distortion ability and the low temperature delaying performance. And acts according to the material maximum nominal particle size is only4.75mm, proposed uses20mm the Marshall test sample definitely to be possible to carry on the mixture ratio design highly.Mechanics behavior divides into the temperature stress and the load stress two parts.The temperature stress for selects the strain gauge gathering method, whether there is to the stress absorption level (HE-AC5) compound beam structure, the contact surface mechanics behavior conducts the research in the temperature drop condition next (30～-30℃) asphalt paving level and the level, and confirms mutually through the ABAQUS value simulation method and the elasticity theory theoretical calculation.Obtains HE-AC5, SBS-AC16and C50san the kind of blend coefficient of contraction, in which HE-AC5is most sensitive, C50overall value small also basic same; Obtains three materials through the return in-30℃-30℃the sector temperature and the linear expansion coefficient mathematics relationship.The test result indicated that,After joins the stress absorption level, because the restraint tensile stress shifts to the stress absorption level structure level, the asphalt paving level temperature tensile stress level dropped about40%.And carries on mechanics computation to the double-decked compound beam structure temperature stress, because highly and length compared to very small, may simplify for the elastic foundation puts up the main beam pulls the condition purely, the union tentative data, calculates the two-course construction is1.1～1.7N/mm3, three structures are1.9～2.8N/mm3. The load stress divides into the progressive load and the repetition load affects two ways to carry on, carries on the load experiment to three kind of compound young Liang test samples, pastes the strain gauge middle the asphalt paving level as well as various contact surfaces key position flank, uses the effusive type gathering strain data, the analysis different caking way as well as spreads the stress absorption level or not various positions mechanics behavior, obtains the double-decked ordinary caking, the double-decked epoxy caking and three ply stress absorption level cakes three kind of structures various positions strain size relations, the strain absolute value aspect, cross is bigger than L/4and the pivot place obviously, L/4cross and the pivot place contact surface all presents the compression condition, also the compression quantity presents the degression by L/4to the pivotTendency.The redundant load size rule and the progressive load are same, and in the entire process, as divides into the initial period fast growth condition take the50th cycle and the later period stable state.Underneath the redundant load appears the accumulation vertical distortion and the snapping back distorts, among, the vertical distortion increases along with the load number of times increases, but the snapping back distorts the entire process to be stable.Uses value simulation method establishment simple support T Liang Quanqiao the model, analysis asphalt paving level thickness and the module, stress absorption factors and so on level thickness and module, to the asphalt paving level interior and the contact surface mechanics influence, and according to the stress absorption level material own stressful condition, the bond timber characteristic, proposes the suggestion thickness scope; Also aims at the coarsening lengthwise grade special position, analyzed has spread around the stress absorption level mechanics change, and has carried on the computation to the wheel rut depth; And to attacked under the load function to spread stress absorption level structure vibrational energy weaken ability to carry on the analysis.Through the paper research, after obtains the cement coagulation mineral pitch flooring to spread the stress absorption level temperature stress behavior and the load stress behavior, obtains spreads the stress absorption level mechanics behavior characteristic, provides the theory support for its correct use.