| Cement concrete pavement is characterized with the advantages such as highstrength, sound stability, good durability, less maintenance cost and being conduciveto car operation at night, etc. As a result, it is widely used in the early highwayconstruction in China. With the booming development of China’s economy, theconstantly increasing traffic volume and axle load have led to varying damages to theearly constructed and newly constructed cement concrete pavements, which severelyaffect their usability performance. Therefore, it is inevitable to maintain or reconstructthe old cement concrete pavements.The largest problem of the asphalt overlay on the old cement concrete pavementsis the reflection crack. There are various preventative measures for reflection crack,however, most of them are not ideal in effect. In order to better solve the problem ofreflection crack, the technology of crushing the old cement concrete plate and thenoverlaying asphalt concrete is then proposed. The technologies of crushing old cementconcrete plate generally consist of three categories: cracking and compacting,crushing and compacting, rubblization. While the resonance rubblization technologywhich is used in such cement concrete pavements with poor plate completeness andpoor structure can crush the concrete plate into high-strength aggregates, which is themost effective crushing technology to solve reflection crack so far.Therefore, this paper takes the trial pavement section of East Second RingReconstruction Project in Fuzhou as the research object, and details the survey andevaluation methods for the damage status of cement concrete pavements, providingbasis for treating the old cement concrete plates before crushing. It also makesresearches on how to determine the construction parameters of resonance crusher, andprobes into the construction method of resonance crushing as well as its evaluationand control of crushing effects based on the specific construction process of trial pavement section. It makes analysis on the forming mechanism of the strength ofcrushing layer as well as the effect on the surroundings by the vibration generatedfrom the construction of resonance rubblization, and makes researches on the dynamicmonitoring of grinding construction technology and the compaction effect. It thenintroduces the measures technology for handling deflection difference and reflectioncrack during asphalt overlaying in detail.This paper points out that the comprehensive survey and correct treatment of thedamage status of cement concrete pavement is an important step for conductingresonance rubblization construction, and proposes to evaluate the structuralperformance index of old pavements with their modulus and deflection factors. Seenfrom the crushing effect, it will be appropriate when the exciting force of theresonance crusher is selected as20MPa or21MPa with the advancing speed of3.0～3.5km/h during the crushing construction, which can not only ensure the crushingeffect which should be reached, but also ensure to obtain the higher productionefficient. The safe distance of the effect on the surroundings by the vibration fromresonance rubblization construction is5m. When conducting the grinding work, it isassumed that the average value of CMV is70as the control criteria for compactionqualification, meanwhile, it needs to conduct reinforcing treatment for the positionwhere the deflection value is less than70(0.01mm).This research indicates that the reconstruction cement concrete pavement withresonance rubblization technology is not only technologically practical, but also canimprove the operating quality of the pavements, so as to effectively prevent reflectioncrack, elongate the service life of the roads and shorten the reconstruction period ofold roads. It is especially suitable for such places as Fuzhou with dense populationand heavy traffic, providing better economic and social benefits. The promotion ofthis technology offers broad prospects for reconstruction of old cement and concretepavements. |
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