3D打印地聚合物砂浆配合比设计及响应面优化模型

Mix Proportion Design and Response Surface Optimization Model for 3D Printing Geopolymer Mortar

摘要:

为了最大限度地提高固废资源化水平，采用再生混凝土微粉（RCP）和矿粉（GGBS），制备3D打印地聚合物，研究了液固比、胶砂比及水胶比对3D打印地聚合物砂浆（3DPGM）可打印性和流变性能的影响机制，并基于响应面法（RSM）构建了流变-力学多目标优化模型。结果表明：液固比、胶砂比及水胶比通过改变浆体的流变行为，可显著调控3DPGM的可打印性；采用动态屈服应力表征可打印性，定量得出具有最优打印窗口（30 min）的配合比；基于方差分析建立动态屈服应力-抗压强度-黏结强度的RSM回归模型，其多目标优化方案预测的最优配合比为液固比0.482、胶砂比0.675、水胶比0.344。

Abstract:

In order to maximize the utilization level of solid waste， 3D printing geopolymer was prepared by using recycled concrete powder （RCP） and mineral powder （GGBS）. The effects of liquid-solid ratio， binder-sand ratio and water-binder ratio on the printability and rheological properties of 3D printing geopolymer mortar （3DPGM） were studied. Based on the response surface method （RSM）， a rheological-mechanical multi-objective optimization model was constructed. The results show that the liquid-solid ratio， binder-sand ratio and water-binder ratio can significantly control the printability of 3DPGM by changing the rheological behavior of the slurry. The printability can be characterized by dynamic yield stress， and the mix ratio with the optimal printing window （30 min） is then quantitatively obtained. Based on the analysis of variance， the RSM regression model of dynamic yield stress-compressive strength-bond strength is established. The optimal mix ratio predicted by the multi-objective optimization scheme is liquid-solid ratio of 0.482， binder-sand ratio of 0.675 and water-binder ratio of 0.344.