【作者】 张俊；

【导师】 朱浮声；

【作者基本信息】 东北大学 ， 结构工程， 2007， 博士

【摘要】 稀浆封层沥青碎石复合路面是指在铺筑沥青碎石后,再在其上摊铺稀浆封层后形成的一种复合式沥青路面,该路面能使稀浆封层和沥青碎石的自身优点同时得到发挥,且又能克服各自不足。到目前为止,有关该复合路面的系统研究还未见报道,基于此,本论文通过室内试验和数值模拟,研究了该复合路面的各项路用性能,然后结合葫六线K29+500-K43+000试验段的施工过程和路用效果调研,对该复合路面的设计参数、施工工艺以及工程造价进行了分析,最后参考相关经验和研究成果,给出了稀浆封层沥青碎石复合路面的设计和施工技术要点。本论文主要研究内容及结果如下所述：(1)利用渗水试验对稀浆封层沥青碎石复合路面的防水性能进行了研究,结果表明该路面的防渗水性能取决于其表层的稀浆封层,稀浆封层采用较细的级配和较大的用水量时,路面防水性能较好,稀浆封层初凝后对其适当进行碾压,能改善稀浆封层沥青碎石复合路面的防水性能。(2)利用车辙试验对稀浆封层沥青碎石复合路面的高温稳定性能进行了研究,研究发现复合路面的高温稳定性能取决于其下部的沥青碎石,沥青碎石采用“S”形级配、粗骨料含量在65%-75%之间时,路面高温稳定性能较好,稀浆封层沥青碎石复合路面的高温稳定性能优于单一的沥青碎石路面。(3)利用低温弯曲试验对稀浆封层沥青碎石复合路面的低温抗裂性能进行了试验研究,结果表明复合路面的低温抗裂性能比沥青混凝土差,与沥青碎石路面基本相当,采用SBR改性剂能提高稀浆封层沥青碎石复合路面的低温抗裂性能。(4)论文对刹车时在稀浆封层沥青碎石复合路面中产生的剪应力进行了数值分析,分析结果说明,刹车引起的剪应力随着胎压、路面摩擦系数和车轮负荷的增大而递增,随着气温的升高而减低。论文还利用自行设计的剪切仪对稀浆封层沥青碎石复合路面的层间黏结性能进行了研究,试验结果说明,复合路面的层间黏结强度随着温度的升高而下降,喷洒粘层油、基层沥青碎石采用较大公称粒径可以提高稀浆封层与基层之间的黏结强度。(5)论文利用有限元方法对稀浆封层沥青碎石复合路面的反射裂缝问题进行了细观数值分析,分析结果表明,稀浆封层沥青碎石复合路面下部的沥青碎石采用较低的沥青含量和间断级配、让复合路面与基层在裂缝附近可以脱开、增大摊铺厚度、加强基层处理质量可以提高复合路面的抗反射裂缝性能。论文还应用脆性涂层法试验分析了稀浆封层沥青碎石复合路面出现反射裂缝时的应力大小和分布,结果表明,脆性涂层裂纹以车轮作用面为发射点向四周扩散,并围绕大粒径碎石扩展,碎石与周围沥青胶砂的界面是拉应力集中的部位。(6)论文最后结合葫六线K29+500-K43+000稀浆封层沥青碎石复合路面的试验段施工实践,对该复合路面的设计参数、施工工艺、运营效果以及工程造价进行了研究,结果表明试验段所采用的设计参数和施工工艺是合理可行的,复合路面路用效果较好,工程造价比具有类似效果的细粒式沥青混凝土明显要低,而与粗粒式沥青混凝土基本相当。论文最后总结出了稀浆封层沥青碎石复合路面的设计、施工技术要点,直接用于指导工程实践。更多还原

【Abstract】 Asphalt macadam pavement sealed by slurry seal consists of a asphalt macadam covered by a slurry seal, the compound pavement can develop strong suit of these two kinds of pavement, while avoiding the shortcoming of them in the mean time. At present, there are not any research reports about the performance, design method, construction technology of the compound pavement, so in the dissertation, the pavement performance of compound pavement are investigated by experiment and numerical simulation. Then, based on the construction process and investigation in-situ of Hu-Liu experiment pavement K29+500-K43+000, design parameter, construction technology and building cost of compound pavement are investigated, a design and construction guide is also given, here some research results and project experiences concerned are considered.The content and investigation results of dissertation are given as follows.(1) Permeability test is performed to study the permeability of slurry seal asphalt macadam compound pavement, test results show that the permeability of compound pavement rest on the slurry seal above it, slurry seal with a fine gradation or more water can acquire a better permeability resistance, and give a proper impaction after initial setting of slurry seal may acquire a better dense surface.(2) Rutting experiment results of Slurry seal asphalt macadam compound pavement show that the rutting resistance ability of compound pavement lies on the lower asphalt macadam. Asphalt macadam with an S type gradation can acquire a good rutting resistance ability, and the coarse aggregate content of asphalt macadam should be about 65-85 percent. The rutting resistance ability of compound pavement is better than it of single asphalt macadam pavement.(3) Low-temperature bend experiment is performed to investigate the low-temperature cracking resistance of compound pavement. Form the experiment results, it can be gotten that the low-temperature cracking resistance of slurry seal above the compound pavement play an important role in improving the low-temperature cracking resistance of whole compound pavement, and the low-temperature cracking resistance of compound pavement is poorer than it of asphalt concrete pavement, while is as good as it of asphalt macadam pavement. SBR modifier can improve the low-temperature cracking resistance of compound pavement.(4) Numerical method has been used to compute shear stress of compound pavement in order to analyze such distress as shoving, sliding and loss of slurry seal. Analysis results indicates that with increasing of tire load, coefficient of friction and tire pressure, shear stress is increment, but shear stress is decreasing while applied a higher temperature, and there is a great probability of shearing yield in hot season. To evaluation the interlayer bonding strength between slurry seal and asphalt macadam, an experimental setup is designed on the basis of improved shear tester, with the aim to model well the actual condition of loaded pavements, experimental results show that the interlayer bonding strength between the slurry seal and asphalt-macadam bottom layer decreases with increasing temperature. Taking some different measures to improve interlayer conditions of pavement can affect obviously the bonding strength, such as using asphalt-macadam mixture with big nominal grain size or making the pavement surface coarse by chisel.(5) Mesoscal FEM method is used to analyze the factors in effecting anti-reflective cracking of slurry seal asphalt macadam compound pavement, the relationship between pulling stress of compound pavement and the factor in effecting it is also gotten. The numerical results indicate that the performance of anti-reflective crack of compound pavement with more asphalt content is better than that with less asphalt, the performance would also be better if compound pavement is separable from old pavement near the crack of it or with a deeper depth, numerical results also indicate that the performance of anti-reflective crack of compound pavement with gap-graded asphalt macadam is better than of it with continuous-graded asphalt macadam. The method of brittle coat is also used to analyze the stress distribution of reflective crack of compound pavement, laboratory results show that the crack of brittle coat propagated around the macadam, and stress concentration occurs at the interface between the macadam and asphalt mixture. Interface between macadam and asphalt mixture in the region of stress concentration is most dangerous in pavement.(6) Based on the construction process and site investigation of Hu-Liu experiment road K29+500-K43+000, design parameter, construction technology and building cost of the compound pavement are investigated. The research results indicate that the compound pavement is a useful pavement and its pavement performance is good, design parameter and construction technology applied in the experiment pavement is feasible, building cost of compound pavement is lower than it of granule asphalt concrete, while almost correspond with coarse asphalt concrete. A design and construction guide of compound pavement is given based on the investigation results, here some expert’s experiences and research results concerned are also considered.更多还原