Research On Performance Of HDPE-Rubber Powder Modified Asphalt And Mixture For Stress Absorbing Layer

With the rapid development of highway construction and unceasing progress of road engineering science and technology, people’s requirement for pavement performance is also higher and higher. Reflection crack is one form of pavement diseases. Setting the stress absorbing layer of modified asphalt mixture can effectively control and delay production and development of reflection cracks, enhance the using performance of asphalt surface, which has good application prospect of promotion.In order to develop stress absorbing layer of modified asphalt mixture to prevent reflection crack, adding HDPE made of waste material and40mesh powder to90#asphalt, using the orthogonal experiment method, grey correlation method and the comprehensive weighted method to carry out the experiment and data analysis. Using orthogonal experiment method for HDPE-rubber tests the preparation technology of compound modified asphalt, using the grey correlation method and the comprehensive weighting method to analyze test data, combining Marshall method and Superpave method to design the mixture, evaluating the pavement performance under the condition of optimum asphalt content.The results show that the stress absorbing layer HDPE-powder power modified asphalt optimum dosage of modifier is:5%HDPE and10%powder, optimum process parameters is: shear rate of4500r/min, shear time of25min, temperature of175℃. Using AC-5graded sand type, HDPE-rubber powder modified asphalt mixture for stress absorbing layer optimum asphalt content is8.93%, The indicators of HDPE-rubber powder modified asphalt mixture satisfy the requirement of stress absorbing layer of modified asphalt mixture technology when using optimum asphalt content. When the temperature is-10℃. HDPE-rubber powder modified asphalt mixture for stress absorbing layer trabecular bending test maximum bending strain is5158με, bending tensile strength13.1MPa, and it has strong resistance to deformation ability at low temperature to prevent the cracks of low temperature. When the temperature is40℃. dynamic stability rut test for3217/mm, When the temperature is60℃,5cm AC-16SBS modified asphalt mixture with adding2cm stress absorbed layer structure of the dynamic stability rut test for5713/mm, Stress absorbing layer in actual working environment of high temperature stable performance. Immersion Marshall Test residual stability was90.4%, the freeze-thaw splitting test and freeze-thaw splitting strength ratio is89.5%, it has good water stability performance. The results can provide the basis for practical application on HDPE rubber powder modified asphalt mixture for stress absorbing layer.