废胶粉改性再生粗骨料沥青混合料性能试验研究

Arshall test research on rubber powder modified recycled coarse aggregate asphalt mixture

基于将建筑垃圾与废旧橡胶循环使用的目的,研究分别以0%,50%和100%取代率的再生粗骨料替换沥青混合料中10 mm~20 mm的天然粗骨料后沥青混合料的性能试验,并进一步在不同再生粗骨料取代率的沥青混合料中以干法掺入20%,30%的废胶粉及以湿法掺入20%的废胶粉,研究不同废胶粉掺量及干掺、湿掺废胶粉后再生粗骨料沥青混合料的马歇尔及车辙试验.结果表明,当废胶粉掺量为0%时,随着再生粗骨料取代率的增多,马歇尔稳定度和动稳定度先增多后减小,流值增多,马歇尔模数和残留稳定度减小,而不论是干掺还是湿掺,马歇尔稳定度降低,流值增多,马歇尔模数和残留稳定度降低,但是湿法工艺降低程度低,动稳定度先增多后减小.因此,沥青混合料中建议再生粗骨料取代率低于50%,而废胶粉以低于20%的掺量湿法掺入.

Based on the purpose of recycling construction waste and waste rubber,we study the Marshall test of asphalt mixture after replacing 10 mm~20 mm natural coarse aggregate in asphalt mixture with recycled coarse aggregate with replacement rate of 0%,50%,and 100%respectively,and further mix 20%,30%of waste rubber powder in dry method and 20%of waste rubber powder in wet method in asphalt mixtures with different recycled coarse aggregate replacement rates to study different waste rubber powders,Marshall and rutting test of recycled coarse aggregate asphalt mixture after dry and wet mixed waste rubber powder.The results show that when the waste rubber powder content is 0%,as the replacement rate of recycled coarse aggregate increases,Marshall Stability and dynamic stability first increase and then decrease,flow value increases,Marshall modulus and residual stability decrease,regardless of dry or wet mixing,Marshall stability decreases,flow value increases,Marshall modulus and residual stability,However,the degree of reduction in the wet process is low,and the dynamic stability first increases and then decreases.Therefore,it is recommended that the replacement rate of recycled coarse aggregate in the asphalt mixture is less than 50%,and the waste rubber powder should be wet-mixed with a content of less than 20%.