水泥混凝土路面固化温度区域特征及其对面板翘曲的影响
Built-in temperature’s regional characteristics of cement concrete pavement and its effect on slab curling

基于全国5个地区的气候参数,采用路面早龄期温度场计算程序,研究了不同海拔和纬度地区水泥混凝土路面固化温度的分布特征; 考虑了面板的固化温度与环境温度的叠加效应,采用三维有限元程序,分析了不同地区固化温度对路面板翘曲和脱空的影响特性。研究结果表明:影响面板行为有板顶、板底固化温度差和固化平均温度; 各地水泥混凝土路面的全年固化温度差的分布基本呈宽矮峰加尖锐峰的双峰组合形态,分别反映负、正固化温度差分布; 负的固化温度差集中在白天形成,变异性大,造成面板板角向上翘曲的趋势,正的固化温度差基本在夜间形成,数值集中,形成面板板角向下翘曲的趋势; 对比不同区域的路面固化温度,高原地区负固化温差最大,拉萨高频次负固化温度差可达-17.2 ℃,其次为北方地区,哈尔滨高频次负固化温度差约为-13.2 ℃; 固化平均温度分布呈单峰型,一般为负值,纬度高的地区气温年较差大,直接导致固化平均温度变异范围大,处于北方的哈尔滨高频次固化平均温度约为-30.4 ℃,拉萨则约为-18.4 ℃; 负的固化平均温度也会引起面板板角向下翘曲,同等条件下其对面板翘曲的影响效应约为固化温度差影响效应的30%～50%; 不同的固化温度特征叠合当地气候环境,对面板服役阶段的翘曲和脱空会产生不同的效应,叠加负固化温度差为-20 ℃时,面板向上翘曲增大约1.5～2.0 mm; 对于面板翘曲明显的地区,建议可选用四边约束结构形式改善路面工程性能。
Based on the climate parameters of five Chinese regions, the distributional characteristics of built-in temperatures of cement concrete pavements in different regions with different altitudes and latitudes were studied by using the computational program of early-age temperature field of cement concrete pavement. The superposition effect of built-in temperature and ambient temperature was considered, the influence characteristics of built-in temperatures in different regions on the curling and uplifting of pavement were analyzed by using the 3D finite element program. Research result shows that slab curling is affected by the built-in average temperature and built-in temperature difference between slab’s top and bottom. Annual built-in temperature differences of cement concrete pavements in different regions present the bimodal distribution characteristics with low-wide and high-cuspidal peaks that respectively denote the distributions of negative and positive differences. Negative built-in temperature difference normally forms in the daytime, and has a large variability, which causes slab corner’s upward curling. While positive built-in temperature difference basically forms in the nighttime, and has a numerical concentration, which causes slab corner’s downward curling. The built-in temperatures of the pavements in different regions were compared, negative built-in temperature difference in the plateau area is the largest, and the high-frequency difference can reach -17.2 ℃ in Lhasa. The second one is in the north area where the high-frequency difference can reach -13.2 ℃ in Harbin. Built-in average temperature is generally negative, and its distribution is the single-peak type. The annual range of air temperature in the high latitude region is larger, which directly results in the larger variation range of built-in average temperature. High-frequency built-in average temperature in Harbin is approximately -30.4 ℃, and approximately -18.4 ℃in