A Preliminary Study on the Usage of Asphalt Transfer Vehicles

The author has introduced some of the application effects and situations of asphalt transfer vehicles in specific applications. During the construction process, Professors Sun Zuwang and Long Shuigen from Chang 'an University went to inspect and offer guidance. They fully affirmed the significant and positive role played by the asphalt mixture transfer vehicle in the construction process. Professor Sun said: "Seeing the stable performance of the asphalt mixture transfer vehicle on the expressway, I was very excited. This is a very memorable innovation in the history of road machinery development in our country. The benefits it brings to highway construction are indescribable." Professor Zhu Mengliang from Changsha Transportation College concluded that the asphalt mixture transfer vehicle has a very obvious effect on solving the temperature segregation problem during the construction of asphalt pavement. In terms of the quality of the paved road surface: After the use of transfer vehicles, due to the secondary stirring of the mixture with a certain degree of gradation segregation on the ground where the vehicles were unloaded by the transfer vehicles, the aggregate segregation of the mixture was significantly improved, thereby significantly reducing the degree of gradation segregation of the paved asphalt road surface and improving its uniformity. Not only is this the case for the road surface, but also for the interior of the pavement structure. The maximum gradation range is 6.85%, the average construction depth is 0.6478mm, the standard deviation is 0.0571mm, and the standard deviation of the permeability coefficient is 3.21ml/min. Compared with the pavement structure without the use of transfer vehicles for paving, the maximum gradation range was improved by 13.03%, the uniformity of the construction depth was increased by 3.92 times, and the uniformity of the permeability coefficient was increased by 17.39 times. In addition, several other aspects have also been improved accordingly.

The smoothness of the paved road surface has been improved: The use of transfer vehicles eliminates the longitudinal waves caused by the pushing effect and collision contact between the paver and the material transport truck, and improves the traction condition of the paver, enabling it to maintain a stable operating speed. Under the same working conditions, the road surface flatness is 1.94mm when using a transfer vehicle, and 2.23mm when not using a transfer vehicle. Facts have proved that the sound can be transported. The paving technology has greatly improved the smoothness of the paved road surface.

Reduce the segregation of the mixture: After using the transfer vehicle, the deviation between the highest and lowest temperatures is 12℃, while without using the transfer vehicle, the temperature deviation reaches 34℃. To further demonstrate its superiority, the author measured and compared the temperature of the mixture. When the temperature variation of the mixed material entering the hopper of the transfer vehicle is between 103℃ and 150℃, with a standard deviation of 12.4, after being stirred and mixed by the transfer vehicle, the temperature variation range of the discharged material is between 136℃ and 148℃, with a standard deviation of 3.5, indicating that the transfer vehicle has a significant improvement effect on temperature segregation.

The use of transfer vehicles has improved the overall quality of pavement construction. It has changed the traditional construction process, completing the transfer, storage and secondary mixing at one time, which has greatly enhanced the quality of construction operations. Adding transfer vehicles during construction can keep the material storage in the paver's silo at a constant or basically unchanged level, thus keeping the attached weight unchanged or changing slightly, which is closer to constant-speed paving. This further improves the uniformity of the paving operation, and the paved road surface has uniform density and structural strength. The transfer paving process can ensure that the paving operation is carried out continuously at a constant speed. The overall quality of the upper road surface has been significantly improved by reducing the lateral joints caused by the shutdown and waiting for materials.

In terms of economic benefits: 1. It has improved the operational efficiency of material transport trucks. As the transfer vehicle can reduce the waiting and unloading time of the material transport trucks at the paving site by more than 50%, and also decrease the number of material transport trucks, the construction cost is lowered. 2. The operational efficiency of the paver has been enhanced. The total storage capacity of the LHZ25A transfer vehicle and the paver hopper is greater than 30 tons, which can ensure that the paver operates continuously at a high paving speed and improve the paving operation efficiency. 3. It has greatly saved the long-term maintenance costs of asphalt pavement. Asphalt pavement paved with transfer vehicles can significantly reduce long-term maintenance costs, extend its service life by at least 40%, and increase the utilization rate of asphalt pavement.

From both scientific theory and practical application perspectives, the transfer vehicle has provided us with significant assistance throughout the entire pavement construction process. Therefore, it is suggested that the highway authorities at all levels and more pavement builders change their mindset and fully recognize the huge role that the asphalt mixture transfer vehicle plays in improving the construction quality of asphalt pavement and extending the service life of the road.