EAC-PCC复合结构层间温度应力研究

Study on Temperature Stress between Electrothermal Asphalt Concrete and Portland Cement Concrete Composite Pavement Structures

制作电热沥青混凝土EAC(Electrothermal Asphalt Concrete)-PCC(Portland Cement Concrete)复合结构试块,在EAC-PCC的层间埋设应变片,通过试验检测EAC-PCC的层间温度应力;建立有限元模型进行数值模拟,分析温度、电压、风速对复合结构层间温度应力的影响.试验表明:温度应力随时间延长逐渐增加,同一时刻不同检测点的温度应力不同;通电240 min时,中心点层间温度应力为0.37 MPa,温度上升了4.6℃.数值模拟表明:通电240 min,中心点层间温度应力为0.41 MPa,温度升高了5.2℃;随着环境温度的降低层间温度应力逐渐增大,负温时层间温度应力快速增大,正温时层间温度应力较小;与环境温度0℃相比,通电240 min时,-10℃、-20℃时层间温度应力分别增加了94.25%、126.72%,而10℃时层间温度应力减少了76.44%;随着通电电压增加,层间温度应力增加的速率变大;随着风速的增加层间温度应力在减小,与风速为0时相比,通电240 min时,风速为1、2、3 m/s的层间温度应力分别减少了15.59%、24.21%、29.66%.

An electrothermal asphalt concrete EAC(Electrothermal Asphalt Concrete)-PCC(Portland Cement Concrete)composite structural test piece was fabricated,in which the strain gauges were pre-embedded between the layers of the EAC-PCC.Through tests,the interlayer temperature stress of the EAC-PCC composite structure was tested.The numerical simulation of the finite element model was carried out to analyze the effects of temperature,voltage and wind speed on the temperature stress between EAC and PCC composite structures.The tests show that the inter-layer temperature force of EAC-PCC increases with time,and the temperature stress of different detection points is different at the same time.When the power is applied for 240 minutes,the interlayer temperature stress at the center point of sample is 0.37 MPa,and the temperature is increased by 4.6℃.The numerical simulation shows that after 240 min of energization,the inter-layer temperature stress at the center point of sample is 0.41 MPa,and the temperature rises by 5.2℃.As the ambient temperature decreases,the interlayer heat stress of the EAC-PCC gradually increases.When the ambient temperature is below 0℃,the interlayer temperature stress increases rapidly.When the ambient temperature is above 0℃,the interlayer temperature stress is small.Compared with the ambient temperature of 0℃,when the energization time is 240 min,the interlaminar temperature stress of EAC-PCC increases by 94.25%and 126.72%respectively at an ambient temperature of-10℃and-20℃.If the ambient temperature is 10℃,the interlayer temperature stress of the EAC-PCC composite structure is reduced by 76.44%.As the energization voltage increases,the rate of increase in the interlayer temperature stress of the EAC-PCC composite structure becomes larger.The interlayer temperature stress decreases as the wind speed increases.Compared with the wind speed of 0,the inter-layer temperature stresses of wind speeds of 1,2 and 3 m/s are reduced by 15.59%,24.21%,and 29.66%respectively,when the current is applied for 240 minutes.