上层恒温下层变温浇筑时碾压沥青混凝土心墙结合面劈裂抗拉试验研究

Splitting Tensile Experimental Research on Interface of Rolling Asphalt Concrete Core Wall under Upper Strata Constant Temperature and Lower Stratum Pouring Variable Temperature

通过制作不同结合面温度的沥青混凝土试件,对结合面进行慢速法劈裂试验,观测结合层面以上25mm和层面以下10、50mm处的温度变化情况,得出结合面温度对强度的影响规律。结果表明,当沥青混凝土结合面温度降至30℃时,上层160℃热料浇筑后,结合层面以下10mm处温度可以升至70℃以上,即达到沥青软化点的1.5倍,满足《水工碾压式沥青混凝土施工规范》要求;30℃结合层面试件孔隙率满足要求,劈裂抗拉强度与母材相比下降10.6%,碾压层面结合质量可以得到保证,为低温条件下碾压沥青混凝土心墙施工提供理论依据和参考。

Through made the asphalt concrete specimens of different interface temperatures, slow splitting tests of interface were carried out to observe variations of temperature at the upper interface 25ram and below interface 10mm and 50mm. And then it obtained the impact law of interface temperature on the strength. Test results show that when the temperature of asphalt concrete interface lowered to 30℃ and the upper was poured 160℃ hot asphalt concrete, the interface temperature below 10mm could rise to the above 70℃, that is 1.5 times of the softening point and meets the regulatory requirements; the porosity of 30℃ interface meets the requirement of specimen; compared with the base material, the strength of splitting tensile reduces 10.6% ; rolter compacted interface quality can be guaranteed. Therefore, it provides a theoretical basis and reference for roller compacted asphalt concrete core wall construction at low temperature conditions.