混凝土再生胶凝材料的活性试验研究

Experimental study on regenerated binding material of concrete

废弃混凝土再生胶凝材料的活性较低。为了提高再生胶凝材料的活性,通过改变熟料掺量、废弃混凝土再生粉煅烧温度、Mg O掺量及水灰比成型胶砂试件,探究各组分掺量对砂浆力学性能的影响,并采用吸水动力学法测定砂浆的孔结构参数(质量吸水率、孔均匀系数、平均孔径),同时测定砂浆高温后的力学性能。结果表明:降低水灰比(0.50至0.35)、降低熟料及Mg O掺量或将废弃混凝土再生粉煅烧控制在600℃左右均有利于提高砂浆抗折/抗压强度,同时达到细化砂浆孔结构的目的。在砂浆中增加熟料掺量(>33%)、降低水灰比(0.50至0.35)、掺入少量(2%)Mg O及将废弃混凝土再生粉煅烧温度控制在600℃左右均有利于提高砂浆高温性能。因此,减少熟料掺量、降低水灰比及调控废弃混凝土再生粉煅烧温度能够提高废弃混凝土再生胶凝材料的活性。

The activity of regenerated binding materials（RBMS） of waste concrete is low. In order to improve the regeneration of the activity of the gelled material, by changing the dosage of clinker calcining temperature, regeneration of waste concrete powder, MgO content and the dosage of water cement mortar, and the water absorption dynamics research method to determine the pore structure parameters of the mortar （quality water absorption and pore uniformity coefficient and average pore diameter）, the determination of mortar after high temperature mechanical properties at the same time. The results show that reducing the ratio of water to cement to 0. 50 to 0. 35） , reducing the content of clinker and MgO, or controlling the calcination of recycled waste concrete powder at 600 -C can improve the flexural/compressive strength of mortar, and at the same time achieve the purpose of refining mortar pore structure. Increasing the amount of clinker （ 〉 33 ）, reducing the water-cement ratio （0.50 to 0. 35）, adding a small amount of MgO and controlling the calcination temperature of recycled waste concrete.