The Research Of High-performance Double Synchronized Crushed Stone Seal For Asphalt Pavement Of Trunk Roads

The development of modern asphalt concrete pavement is bringing forward the higherdemands to the road performance. It is not only to meet the requirements of traffic accesswhich is the basic conditions, but needs the functional of more security, economic,comfortable and the use quality, good durability. However, in many regions, due to theimpact of raw materials and construction costs, some performance of trunk road asphaltpavement can’t be guaranteed. The pavement is prone to flaking, pits and other waterdamage, and pavement skid resistance tends to decay rapidly. To this end, in this paper, thetechnology of high-performance synchronized crushed stone seal for trunk road asphaltpavement is studied.There are many shortcomings of synchronized crushed stone seal in practicalapplication, like peeling off, flushing, poor driving comfort and so on. So doublesynchronized crushed stone seal used for arterial highway asphalt above layer is studied,and some road performance of synchronized crushed stone seal is optimized. First, stonecompatibility of double synchronized crushed stone seal was studied. The lower layer stonediameter should be larger than the upper stone diameter, and the upper stone can betterembedded in the lower stone gaps. Which make the road surface flatness, the drivingcomfort and pavement durability improve. Then the asphalt dosage of corresponding to thedifferent stone size is obtained by theoretical calculation. And to get each file stone amountthrough the shop test method, on this basis adjusting dosage of asphalt and stone to maketest plan. The preliminary stone and asphalt content was determined by stone falls off ratein brush test.The design of material composition on the upper and lower double synchronizedcrushed stone seal were studied. Develop appropriate test pilot programs based on differentindicators. Through a series of road performance test, including: High temperatureperformance test, Low temperature performance test, water stability, Anti-slip test and soon. Determined the double synchronized crushed stone seal material composition. On thebasis of theoretical analysis and experimental research, proposed a multi-index controlsystem based on road performance of double synchronized crushed stone seal. Use hightemperature rutting test as bleeding control targets. Use aggregate dropout rate of sweepingtest, water immersion test, and low temperature testing as adhesion properties controltargets. Use anti-sliding value as skid resistance the index. Use water permeabilitycoefficient as drainage indicators. Through wrapping the upper aggregates with asphalt, and mixing with rubberparticles of different mesh numbers (8,16and30mesh), improve its high temperatureperformance and adhesive properties. By conducting the rutting tests and sweeping brushtests, do the comparative analysis, and get the conclusion that when the content of16meshrubber particles is2%of the upper aggregates, the comprehensive road performance ofsynchronized crushed stone seal is the best, and the waterproofing and drainageperformance is better, and the pavement skid resistance condition meet the requirements.Due to the dampening properties, the rubber particles have noise depressing capacities, andit can improve the driving comfort. Comparing to the cost of asphalt pavement, of whichthe thickness is4cm, the synchronized crushed stone seal that was mixed with rubberparticles has better economic benefits, and it is worthy of promotion in the future.