【作者】 徐永丽；

【导师】 程培峰；

【作者基本信息】 东北林业大学 ， 林区交通工程， 2013， 博士

【摘要】 论文以水泥混凝土桥面沥青铺装层的底部加铺高弹性沥青砂应力吸收层结构为研究对象,采用室内小型试验和ABAQUS数值模拟手段,对加铺应力吸收层前后的力学行为进行研究,重点关注沥青铺装层内部、应力吸收层内部和与桥面水泥混凝土粘结界面处。对于高弹性沥青砂应力吸收层材料进行了配合比设计和性能检验,采用马歇尔方法对三种级配进行配合比设计、劈裂强度试验、水稳定性试验、车辙试验、小梁弯曲试验和低温冻断试验等路用性能检验,确定最佳级配。并采用小梁弯曲试验和低温冻断试验评价,高弹性沥青砂应力吸收层材料具有良好的变形能力和低温延展性能。并根据材料最大公称粒径仅为4.75mm,依据体积指标对比试验结果,提出采用20mm高度,双面击实50次制作马歇尔试件方法,完全可以进行配合比设计。力学行为分为温度应力和荷载应力两部分。温度应力为采用应变片采集方式,对有无应力吸收层(HE-AC5)的复合梁结构,在温度降低条件下(-30℃～30℃)沥青铺装层和层间界面的力学行为进行研究,并通过ABAQUS数值模拟手段和弹性力学理论计算相互验证。得到HE-AC5、SBS-AC16和C50三种混合料的收缩系数,其中HE-AC5最为敏感,C50最为稳定,整体数值小；通过回归得到三种材料在-30℃-30℃区间内的温度与线膨胀系数的数学关系式。组合结构加入应力吸收层后,由于约束拉应力转移到应力吸收层结构层,沥青铺装层的温度拉应力水平下降了40%左右。对双层复合梁结构温度应力进行力学计算,由于高度与长度比很小,可以简化为弹性地基上梁的纯拉状态,结合实测数据,计算出双层结构的层间摩阻力系数Cx为1.1～1.7N/mm3,三层结构的Cx为1.9～2.8N/mm3。荷载应力分为静载和重复荷载作用两种方式进行,对双层普通粘结、双层环氧粘结和三层应力吸收层粘结三种复合小梁试件进行加载实验,在沥青铺装层中部以及各界面关键位置的外侧贴应变片,采用静态方式采集应变数据,分析不同粘结方式以及加铺应力吸收层与否的各位置力学行为,得到三种结构的各位置应变大小关系。应变绝对值方面,跨中明显大于L/4和支点处,L/4跨和支点处界面都呈现压缩状态,且压缩量由L/4向支点呈现递减趋势。重复荷载的大小规律与静载相似,并在全过程中,以第50个周期为界分为初期快速增长态和后期稳定态。重复荷载下方出现累积竖向变形和回弹变形,其中,竖向变形随着加载次数增加而增加,而回弹变形全过程较为稳定。沥青铺装层厚度和模量、应力吸收层厚度和模量等参数,对沥青铺装层内部和界面力学影响,采用数值模拟方法建立简支T型梁全桥模型分析。根据应力吸收层材料自身受力状态,结合材料特点,提出建议厚度范围；针对大纵坡特殊受力条件,分析了加铺应力吸收层前后的力学变化,并计算了车辙深度；并对冲击荷载作用下加铺应力吸收层结构的振动能量衰减能力水平进行了分析。通过论文的研究,得到水泥混凝土沥青桥面铺装加铺应力吸收层后的温度应力行为和荷载应力行为,得出加铺应力吸收层的力学行为特点,为其正确使用提供理论支撑。更多还原

【Abstract】 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.更多还原