心墙结合面温度对碾压式沥青混凝土强度影响

Research on the Strength Influence of Roller Compacted Asphalt on Concrete Core Wall Combining Surface Temperature

通过制作不同结合面温度的沥青混凝土试件进行直剪试验和小梁弯曲试验,研究了结合面温度变化对其力学性能的影响规律。试验表明:结合面温度降低为-25℃时,试件的孔隙率已不能满足规范中小于2%的要求,其余试件孔隙率均满足要求;抗剪断强度、抗弯强度及最大弯拉应变随结合面温度的降低均有所下降,结合面温度为30℃的分层成型试件与一次成型试件相比分别下降了8.1%、4.5%、8.3%,结合面强度没有明显下降,碾压层面结合质量可以得到保证,为冬季低温条件下碾压沥青混凝土心墙的施工提供了理论依据。

By making the specimens of different combine surface temperatures, direct shear tests and trabeeular bending tests are car- ried out. The influence law of binding surface temperature changes on its mechanical properties is studied. Experiments show that： the specimen porosity has been unable to meet the specification requirement of less than 2 %, when the combination of surface temper- ature decreased to --25 ℃, the rest of the specimen porosity could satisfy the requirements; the shear strength, bending strength and maximum bending strain were decreased with the decreasing of binding surface temperature, the layered molded specimens based on 30 ℃ binding surface temperature compared with the once-forming specimens decreased by 8. 1%, 4. 5 %, 8. 3 %. No significant de- crease in the strength of joint surface, roller compacted combine quality level can be guaranteed, and provides a theoretical basis for roller compacted asphalt concrete core wall construction under winter negative temperature conditions.