石灰岩和花岗岩温拌沥青混合料劈裂强度对比

Comparative Study on Splitting Strengths between WMA with Limestone and WMA with Granite

为了比较研究以石灰岩和花岗岩作为集料的温拌沥青混合料的劈裂强度和水稳定性,首先,进行不同Sasobit温拌剂掺量(0,2%,2.5%,3%,3.5%,4%)条件下的沥青表面自由能试验;然后对成型试件进行劈裂强度试验;最后计算表面自由能和黏附功。结果表明:无论石灰岩还是花岗岩,沥青表面自由能和黏附功与对应混合料冻融前、后劈裂强度变化规律相似,能够较好地反映劈裂强度的波动性;石灰岩与沥青黏附功比花岗岩与沥青的黏附功小,但石灰岩混合料劈裂强度较大,石灰岩的冻融劈裂强度比(TSR)与Sasobit的掺量呈负相关,而花岗岩则呈正相关,且石灰岩的TSR明显优于花岗岩的TSR;相同粒径的石灰岩SSA至少约为花岗岩SSA的1.4倍,石灰岩与沥青具有较大的黏附面积。

WAM with mix agent In order to compare the splitting strengths and moisture stability between WMA with limestone and granite as aggregate, first, the test on surface free energy of asphalt with different Sasobit warm contents （0, 2%, 2. 5%, 3%, 3.5%, 4% ） is conducted. Then, the splitting strength test on corresponding molded specimens is conducted. At last, the surface free energy and work of adhesion are calculated. The result shows that （ 1 ） regardless of limestone or granite as aggregate, the variation rules of the surface free energy and work of adhesion of asphalt are similar to that of the splitting strength of the corresponding mixture before and after freezing-thawing, which can reflect the volatility of splitting strength; （2） the adhesion work of limestone is lower than that of granite, but the splitting limestone is higher, the tensile strength ratio （TSR） of limestone is negatively co of the mixture with with Sasobit~ , but the TSR of granite is on the contrary, and the TSR of limestone is obviously superior to that of granite ; （3） when the diameter of limestone and granite is the same, the SSA of limestone is at least about 1.4 times of that of granite, and limestone and asphalt has larger area of adhesion.