Study On Synthetically Anti-cracking Technique Of Semi-rigid Base Asphalt Pavement

The any structure layer of the subgrade , the subbase , the base and the pavement of semi- rigid base asphalt pavement took place to split, the cracks will reflect to its up and next structure layer at corresponding place. So in order to resist cracking ,we must synthetically consider various sorts of elements of influencing semi- rigid base asphalt pavement cracking, and from whole set out,adopt many path, many outlet ,from next to up gradually the layer solve the cracking problem of semi- rigid base asphalt pavement.SubgradeFrom construcking, point solve the problem of compactness detecting and subgrade settlement observation, solve the subgrade settlement bad-distributed problem.SubbasePut forward using low dosage(cement dose 2.5%~3%) framework dense gradation cement stabilized macadam subbase structure, replace traditional and easy cracking cement soil, lime soil, lime-fly ash etc. subbase structure.BaseSolving the base cracking problem through the change of forming method and gradation optimization.1. Put forward to the optimization gradation of vibration forming framework dense gradation cement stabilized macadam base, and cement dose of different design strength.2. Passing to the dry shrinking experiment and fracture toughness experiment of different gradation of suspended and framework dense in different forming method, analysising the influence of forming method, gradation, powder content less than 0.075 mm, construction season, construction well-distributed, moisture capacity, cement dose etc.to static forming method suspended gradation and vibration forming method framework dense gradation cement stabilized macadam base cracking.3. Using the analysising of damage and fracture mechanics theories , limited dollar calculating and testing proving there approach to discuss anti-cracking mechanism of framework dense gradation cement stabilized macadam base.4. Using the damage mechanics and fracture mechanics theories, the methods of mathematic statistic and linear regression to estimate the cracking distance of framework dense gradation cement stabilized macadam base.5. Application ANSYS limited dollar software to calculate fatigue life used and crack stress intensity factor . For solve at make use of a limited dollar to analysis damaging and fracturing of cement stabilized macadam base, can't reflection the problem of gradation influence fatigue life used and crack stress intensity factor, put forward using crack expanding weighting (Rmin) to indicate suspended gradation and framework dense gradation.6. Put forward to the construction technique complete set of vibration forming method and framework dense gradation.Pavement Passing the synthetically measure before, to solve all the cracking problem under the pavement, essentially dispel the reflection.1. This text is main to solve the bad-distributed problem causing of asphalt road cracking through GTM forming method, framework dense gradation optimization , using aggregate rolling technique, design and construction.2. Using the analysising of damage and fracture mechanics theories , limited dollar calculating and testing proving there approach to discuss anti-cracking mechanism of framework dense gradation bituminous mixtures designed with GTM.3. Passing optimization study of AC-13 asphalt mixtures designed with GTM, low temperature bend experiment, low temperature fatigue test and cracking temperature experiment, put forward a framework dense gradation bituminous mixtures design method according to the anti- cracking function.4. Put forward to the construction technique complete set of GTM forming method and framework dense gradation.Construcking and Detecting Technique1. Using Rayleigh wave to detect compactness possesses the excellence of high precision, no damaging and speed quick, we can use it to solve the problems of costing a lot of time and work, and easy taking disguise etc. when we detect compactness use traditional method.2. Establishment a mechanics model of aggregate rolling method, and analysising the mechanism that can improve pavement anti-cracking level.Test roadTest road research enunciate that the comprehensive anti- cracking technique of semi- rigid base asphalt pavement is advanced in theories, the technique is practicable, engineering application is effective.