基于总功效系数法的自保温再生混凝土配合比优化

Mix proportion optimization of self-insulation and recycled concrete based on total efficiency coefficient method

基于总功效系数法,以抗压强度和导热系数为评价指标,选取水胶比、再生粗骨料取代率、再生细骨料取代率、玻化微珠体积掺量和活性化尾矿微粉掺量为关键影响因素,设计了自保温再生混凝土配合比正交试验,研究了各因素对其性能的影响。结果表明:玻化微珠体积掺量是影响抗压强度和导热系数的主要因素,抗压强度和导热系数随玻化微珠体积掺量的增加而降低;再生粗骨料取代率是影响抗压强度和导热系数的重要因素,抗压强度随再生粗骨料取代率的增加而降低,导热系数随再生粗骨料取代率的增加而先降低、后增加。通过设计优化,可获得28 d抗压强度达到19.0 MPa、导热系数为0.429 W/(m·K)的自保温再生混凝土。

Based on the total efficiency coefficient method, and by compressive strength and thermal conductivity as the evaluation index, the water-binder ratio, the replacement ratio of recycled coarse aggregate, replacement ratio recycled fine aggregate, glazed hollow beads volume content and activated tailings powder are selected to optimize the self-insulation and recycled concrete mix proportion design and to study the influence of above factors on its performance. The results show that the glazed hollow beads volume content is the main influence factor on the compressive strength and thermal conductivity, the compressive strength and thermal conductivity decrease with the glazed hollow beads volume content increase. The recycled coarse aggregate replacement rate is the important factor of effect the compressive strength and thermal conductivity, the compressive strength decreases with the recycled coarse aggregate replacement increase,and the coefficient of thermal conductivity decreases and then increases with the recycled coarse aggregate replacement rate increase. By the design optimization, the self-insulation and recycled concrete with 19.0 MPa of 28 d compressive strength and 0. 429 W/（ m · K ） of thermal conductivity coefficient should be obtained.