Study On Crack Treatment Skill Of Expressway Asphalt Pavement In Fujian Province

For the problems of Fujian province highway asphalt pavement cracks treatment technical on the warm-wet climate conditions, through the methods of field investigation, interior and outdoor test and theoretical analysis, the study would be conducted for the technique characteristics of cracks treatment in asphalt pavement, influence factors and failure modes, the material performance of cracks treatment and technical standards, the structure mechanical characteristics of cracks treatment at between static and dynamic load with temperature and failure mechanism. The specific work and results are as follows.The field investigation found that the main factors of the effect of cracks treatment on asphalt pavement on the warm-wet area includes water damage, overloading transportation, high temperature,the method selection of crack correspondence, the material performance and the matching process. The mainly crack treatment failure mode existed the packing material debonding, tires whirling, the packing material extruding and the location staggered joints of check crack. There was important to promoting the effect of crack treatment on the warm-wet area for waterproof, anti high temperature, choosing the right method, the technology implementation between packing with waterproof and debonding.Crack filling material of laboratory performance test show:sealant softening point, elongation, cone penetration and sticky toughness index of the whole level is higher, low temperature bonding tensile and elastic recovery of two performance indicators is relatively low; which is also very unfavorable to the hot and humid areas, analysis showed that there is still exist great differences in climate, even in Fujian Province, to the northwest of Fujian in taking into account the high temperature and waterproof at the same time, should also pay special attention to select good low temperature performance of joint sealant.Under the different working conditions, the response of asphalt pavement crack filling treatment mechanics characteristics of the numerical analysis found that:for side wall debonding parameters was as follows:axial load> joint sealant modulus> interface penalty factor> groove width> groove depth> slit width. For heavy traffic road should improve the bonding lever, the caulking adopt the low modulus, high ductility, strong adhesive material, pay attention to corresponding groove width settings.Using the dynamic finite element analysis method, research on asphalt pavement crack fillkng treatment structure of dynamic response features found that:due to the viscoelastic property of joint sealant,under the same amplitude dynamic load, the side wall filler stress increases, the faster the speed the greater the stress; parameters were found the groove depth is more significant, to reduce the dynamic load and high speed caused the stress increase problem, need to consider a reasonable set of material viscosity.Based on finite element numerical analysis to study the force mechanical response of notch joint filler under periodical dynamic heating and mutant cooling,analysis found that:low and mutant cooling prone to cause debonding of sidewall joint sealant; the better the performance of joint sealant is flabby, the greater the groove width (10-30 mm), the greater the debonding favorable for preventing low temperature level.Above studies show that the effect of the treatment technology of asphalt pavement mainly depends on the balance between road condition and notch structure-material properties-process. Finally, based on the different environment zoning and materials research, puts forward the evaluation methods and indicators of the hot and humid regions fillers in four districts of three joint filler technical standards and pressure joints with anti swept away. The study suggests that the humid tropics general sections of standard groove can use 15mm wide and 15mm deep size combination, winter low-temperature region suggested 30mm slot width andl5mm groove depth size combination. For waterproof problems under high temperature and pumping slurry crack problem of semi-rigid base to hot and humid climate in fujian, to carry out a special experimental research about the epoxy back cover and polymer grouting technology.