摘要
为分析低温环境下层间结合力学性能随温度变化的规律,针对冬季沥青混凝土心墙连续多层施工中的温控难题,通过在施工现场开展沥青混凝土心墙模拟摊铺试验,精准调控结合面温度(-5℃至70℃),对含结合面的沥青混凝土心墙进行钻芯取样,制作带有不同温度结合面的3种试件(小梁弯曲试件、拉伸试件、SCB试件),一体成型试件作为对照,进行力学试验,揭示其力学性能演化规律。研究表明,结合面温度40℃为一个重要临界点,在该温度下,沥青混凝土的力学性能呈现出相对稳定的特征,与一体成型试件相比,虽力学性能有所下降,抗弯强度下降11.39%、最大弯拉应变下降9.65%、抗拉强度下降7.89%、临界拉应变下降16.11%、临界应力强度因子和断裂能分别下降19.21%和11.78%,但能在实际工程应用中表现出显著的稳定性。结合PFC数值模拟,不同结合面温度下沥青混凝土力学性能模拟结果与物理试验数据高度一致,验证了模型的可靠性。综上,沥青混凝土心墙结合面温度为40℃,试件达到稳定,在40~70℃时,温度越高,对沥青混凝土心墙的抗弯强度、抗拉强度及断裂能越有利。
In order to analyze the variation law of the mechanical properties of the interlayer bonding with temperature in low temperature environment,aiming at the problem of temperature control in the continuous multilayer construction of asphalt concrete core wall in winter,the simulated paving test of asphalt concrete core wall was carried out on the construction site,and the temperature of the bonding surface(—5°C to 70°C)was accurately controlled.The asphalt concrete core wall with bonding surface was drilled and sampled,and three kinds of specimens with different temperature bonding surfaces(trabecular bending specimens,tensile specimens and SCB specimens)were made.The mechanical test was carried out with the integrated forming specimens as the control to reveal the evolution law of its mechanical properties.The research shows that the joint surface temperature of 40 C is an important critical point.At this temperature,the mechanical properties of asphalt concrete show relatively stable characteristics.Compared with the integrated molding specimen,although the mechanical properties decrease,the flexural strength decreases by 11.39%,the maximum flexural tensile strain decreases by 9.65%,the tensile strength decreases by 7.89%,the critical tensile strain decreases by 16.11%,the critical stress intensity factor and fracture energy decrease by 19.21%and 11.78%,respectively,but it can show significant stability in practical engineering applications.Combined with PFC numerical simulation,the simulation results of mechanical properties of asphalt concrete under different joint surface temperatures are highly consistent with the physical test data,which verifies the reliability of the model.In summary,the temperature of the joint surface of the asphalt concrete core wall is 40 C,and the specimen reaches stability.At 40 to 70 C,the higher the temperature,the more favorable the bending strength,tensile strength and fracture energy of the asphalt concrete core wall.
作者
罗子阳
杨武
韩德强
潘德优
LUO Zi-yang;YANG Wu;HAN De-qiang;PAN De-you(Xinjiang Research Center for Hydraulic Rock and Soil Engineering and Structural Engineering/College of Water Resources and Civil Engineering,Xinjiang Agricultural University,Urumqi 830052,China;Construction Management Center of the Kuergan Water Conservancy Hub Project,Akto 844000,China)
出处
《新疆农业大学学报》
2025年第4期339-346,共8页
Journal of Xinjiang Agricultural University
基金
国家自然科学基金项目(52469025)
新疆维吾尔自治区天池英才引进项目
关键词
沥青混凝土心墙
低温施工
性能补偿效应
离散元模拟
asphalt concrete core wall
low-temperature construction
performance compensation effect
discrete element simulation
