再生骨料透水混凝土亚高温-冷却性能研究

Study on the Sub-high Temperature and Cooling Performance of Recycled Aggregate Pervious Concrete

以再生骨料透水混凝土为对象,设计不同试验,研究其在亚高温-冷却条件下强度变化规律,试验包括常温、4种亚高温(80、120、160℃及200℃)及3种冷却方式(水冷、风冷、自然冷却),并在此基础上建立BP神经网络预测模型,预测其强度性能。结果表明,随温度升高,再生骨料透水混凝土强度先增大后减小,80℃时抗压强度最高,为14.65MPa,与常温下相比,增幅45.54%;冷却会引起强度损失,且加热温度越高、冷却越剧烈,强度损失越大,200℃加热温度、浸水冷却下强度损失最大,为46.5%;同时这种变化还具备可预测性,相对误差在10%左右。

Taking recycled aggregates pervious concrete as research object,different tests are designed to study the strength variation of concrete under sub-high temperature-cooling conditions,including normal temperature,four kinds of sub-high temperature(80℃,120℃,160℃and 200℃)and three cooling ways(water cooling,air cooling and natural cooling).On this basis,the BP neural network prediction model is established to predict the strength performance.The results show that,with the increase of temperature,the strength of recycled aggregate pervious concrete increases first and then decreases.The compressive strength is the highest at 80℃,which is 14.65 MPa and is an increase of 45.54%compared with that at normal temperature.Cooling will cause strength loss,and the higher the heating temperature and the more severe the cooling,the greater the strength loss.The maximum strength loss is 46.5%under the condition of 200℃heating temperature and water immersion cooling.The change of concrete strength under different sub-high temperature-cooling condition is predictable,and the relative prediction error is about 10%.