| China is a country with a large number of mountain and water ranges,with the rapid development of highway traffic construction,it is facing more and more complex natural environments.Tunnels,which can overcome the elevation obstacles,shorten the length of line,reduce the slope and curvature,have been widely used in highway constructions,with a growing trend to develop year by year.Recently,the proportion of long tunnels in highway construction is getting much higher.However,there would be a lot of “soft ribs” in the long tunnels which were paved by ordinary hot mixed asphalt mixture,such as,large dust during the construction period,high energy consumption,water damage during the operation period,problems of durability,anti-fire and traffic safety.Absolutely,these weaknesses are limiting the ordinary hot mixed asphalt mixture in road tunnel pavement applications.In order to solve these problems,this paper has carried out pavement structure and material research according to the special environment in the highway tunnels.Through the preparation of hyper-branched polymer surface modified nano-modifier particles,and through the ways of Fourier transform infrared spectroscopy(FTIR)and thermo gravimetric analysis(TG)to get the characterization of the micro-structure of the system,it is proved to achieve the hyper-branched polymer surface covalently modified nano-modifier particles.To modify the epoxy resin with hyper-branched polymer surface modified nano-modifier particles and combine with the development of compatibilizer and the curing agent system at room temperature.A kind of cold-mix epoxy asphalt binder was developed with decolorized asphalt and materials above,which has the excellent features of good mechanical properties,low temperature toughness,suitable for tunnel pavement.And the curing mechanism was explained with the way of two-dimensional correlation infrared spectroscopy,that is,the epoxy group and the synergistic curing agent ZW-2 in complex curing agent system react incomplete curing firstly,forming a part of the gel network.And then,at 25 ? constant temperature,continue react with the basic curing agent CW-1 amine group,and producing the formation of hydroxyl and ether bond,and finally react with hydroxyl groups to produce different structures of ether bond;The kinetics of curing reaction of cold epoxy epoxide system was studied by means of non-isothermal DSC differential scanningcalorimetry.The activation energies of the system were calculated by Kissinger and Ozawa models.The curing kinetics of the system was consistent with autocatalysis.And the experimental results are in agreement with the theoretical results of the Sesták-Berggren model.Based on the analysis of the design method of the porous asphalt mixture and the results of the indoor tests,the design and experiment of the ratio of the porous colored cold-mix epoxy asphalt mixture and the optimum asphalt dosage were put forward from the design of the key indicators.The durability design of the porous colored cold-mix epoxy asphalt mixture is designed with the target porosity of 20%.Finally,the optimum ratio of oil and gradation composition of porous colored cold-mix epoxy asphalt mixture are determined,which provide the data reference for its application promotion.At the same time,it can be seen that the influence of the toner on the stability of the mixture Marshall is very small and negligible by analyzing the Marshall stability change of the colored porous cold asphalt mixture under different toner dosage.The high temperature performance,low temperature performance,fatigue performance and water stability of the cold epoxy asphalt mixture were analyzed by laboratory tests,which indicated that it had excellent road performance and the construction technology was simple and controllable.Through the oxygen index,smoke density,bound combustion test,it is concluded that cold-mix epoxy asphalt has a higher oxygen index and lower smoke density level compared with ordinary modified asphalt and high viscosity modified asphalt.Under the same combustion conditions,the combustion quality loss and the structural damage of the porous colored asphalt mixture are better than those of the ordinary modified asphalt mixture and the high viscosity asphalt mixture,which indicates that the cold-mix epoxy has better flame retardant performance and can achieve a real zero emissions in the production and construction process,as one of the most environmentally friendly mixture production modes,while ensuring the quality of construction at the same time conducive to the health of construction workers.By comparing and analyzing the various evaluation methods of tunneling illumination,the visual effect method based on reaction time can be used to evaluate the influence of road color on visual effect in tunnel lighting environment.Through three different road colors as the research objects,the relationship between the reaction time and the color of the road,the brightness of the background,the contrast of the visual and the eccentricity of the visual scale are related to the change of the reaction time between the different background brightness,the visual contrast and the eccentricity ofthe driver in the middle visual state.The increase of background brightness and the increase of visual contrast,the reaction time of the driver decreases and the reaction speed is faster.As the eccentricity increases,the reaction time increases,that is,the reaction rate becomes slower.In the case of various tests,when the tunnel surface is green,compared with black and red road subjects the shortest reaction time,the fastest response speed,so it can enhance the ability to respond to emergencies in the process of driving,achieve the purpose of energy saving in the same tunnel driving visual conditions and improve the safety of tunnel driving.Through the study of the construction technology of porous colored cold-mix epoxy asphalt mixture in the tunnel,it is found that the construction technology is simple and controllable and has good application prospect.In this paper,it combined the polymer materials science,road engineering,colorology,traffic safety and other disciplines,where the establishment of tunnel pavement research design and setting methods are settled to fill the gaps in this research.And it promotes the application of theoretical basis and technical support,so as to promotes the development and technological progress of highway tunnel construction in China. |
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