温度对水工沥青混凝土弯曲性能影响的试验

Effect of temperature on bending performance of hydraulic asphalt concrete beams

本文针对-30℃~25℃温度条件下的水工沥青混凝土开展了小梁弯曲试验,重点分析温度对水工沥青混凝土面板的各项力学性能指标的影响。试验结果表明:(1)温度对水工沥青混凝土的应力-应变特性有着密切关系。在-30℃~0℃温度区间,应力-应变曲线近似成线性关系,试件的应力达到峰值后发生断崖式下跌,呈脆性破坏;在0℃~25℃温度区间,试件应力达到峰值后经历一定程度的塑性变形后断裂,呈延性破坏。(2)水工沥青混凝土随着温度升高,其抗弯强度、弯曲模量逐渐降低,变形能力提高;随着温度的降低,峰值应变减小。(3)研究提出的经验公式较好反映了水工沥青混凝土在不同温度条件下弯曲性能的变化特性,与试验结果吻合较好。

In this work,bending tests on hydraulic asphalt concrete beams under temperature of-30°C to 25°C are carried out,and the influence of temperature on mechanical properties of hydraulic asphalt concrete panels is examined.Results show that,(1)the stress-strain characteristics of the concrete is closely related to temperature.In the range of-30°C to 0°C,the stress-strain curve is nearly linear,and the stress of the specimen reaches the peak first and then plummets,showing a brittle failure.In the range of 0°C to 25°C,the specimen undergoes a certain degree of plastic deformation after its peak stress,and then it fractures,showing a ductile failure;(2)As temperature rises,both flexural strength and flexural modulus of the concrete decrease gradually,and deformation capacity increases;as temperature drops,peak strain decreases;(3)For concrete under different temperature conditions,an empirical formula is put forward in this study and it calculates the variations in flexural properties to a good agreement with the test results.