The Numerical Analysis Of Composite Pavement Under Moving Load And Research On Detection Techniques

A lot of old cement concrete pavements has entered the maintenance phase, exploring how to overlay the new pavement on the old cement concrete pavements has become a very valuable research topic, however, pavement maintenance can not only depend on deflection which is for theoretical calculation and quality acceptance, because it is not only a true reflection of the state of the internal pavement structure, analysis results are also too one-sided. The article uses more mature finite element method to analyze the responses of the internal pavement structure, and provides reference and basis for the maintenance and design of pavement in future.Pavement detection is a true reflection of the state of the internal pavement and further development of theoretical analysis of the pavement, but the way for pavement detection that can be used directly are limited, the fiber-optic sensor technique is pay much attention, but it still be placed in the research and development stage, the technique is still not mature and the price is expensive, it is not suitable for study, in the resistance strain checkout equipment aspect, although its price is low, its stability is poor and its anti-interference capability is low, it is also not suitable for using in the pavement which environment is complex.The article studies sphere of application and performance of checkout equipment, and then chooses JMZX-215 submerged concrete strain gauge in the consideration of environmental factors and application prospects. Vibrational chord strain gauge has characteristics of good stability, high anti-interference capability, cost-effective, convenient data collection and testing the accumulated value of strain, and through the transformation of the strain gauge structure to solve problems of high-temperature, corrosion, compression, durability.The article analysis the impact of speed to the pavement structure basing on the numerical analysis of pavement structure under the load in different speeds. The results show that the road displacement and stress (strain) not only have something to do with its own natural frequency and loading time, but also other factors, and pavement response decreases with the increase in speed, slow heavy vehicles most seriously affect the pavement. The article studies the real conditions of internal pavement structure and proves the strain gauge detection program through comparison and analysis between testing data and calculation data. The data show that the deflection complies with design requirement and the pavement is in good running now. After the reopening of traffic, the pavement surface is more stable than the grass-roots, but the grass-roots has lager strain than pavement surface under the load, and the grass-roots can easily become plastic under the heavy load. At the same time, it also proves that the vibrational chord strain gauge can be effectively used in the pavement detection and provides a new detection technique for long-term monitoring of the pavement.