矿渣基轻质泡沫混凝土的增强研究

Reinforcing for Slag-based Lightweight Foamed Concrete

以碱激发矿渣为主要胶凝组分,利用物理发泡技术制备了矿渣聚合物泡沫混凝土。通过XRD表征了不同基体组成对泡沫混凝土物相组成的影响;通过Image-Pro Plus表征了不同基体组成对泡沫混凝土气孔结构的影响。综合分析了不同基体组成对矿渣聚合物泡沫混凝土基体强度以及气孔结构的影响,重点研究了低密度矿渣基泡沫混凝土的强度优化。研究表明未掺加泡沫的地质聚合物基体强度作为矿渣聚合物泡沫混凝土的强度基数,而孔结构则代表了随着泡沫掺加矿渣聚合物泡沫混凝土保留其基体强度的能力,对于低密度的泡沫混凝土,提高其保留基体强度的能力为强度优化的根本出发点。基于以上理论对矿渣聚合物泡沫混凝土掺加粉煤灰进行孔结构优化,掺加水泥进行基体增强的强度分步优化,使1800 m L泡沫掺量(干密度400 kg/m^3)的矿渣基泡沫混凝土强度增加103%,使其强度由1.43 MPa提高至2.91 MPa。

Alkali activated slag,as the main gelling ingredients,was used to prepare slag polymer foamed concrete by the physical foaming technology. The influence of different composition foamed concrete matrix on the phase composition can be indicated by XRD,the affected air-void structures of the foamed concrete were investigated by image process software（Image-Pro Plus）. This study presents the comprehensive analysis about the effect that different composition foamed concretes matrix make for the matrix compressive strength and the air-void structures,this study is mainly focused on the low density of the slag polymer foamed concrete strength optimization. The results indicate that the matrix strength is the basement strength of the slag polymer foamed concrete,and the air-void structure represent the ability that the polymer foamed concrete preserve its strength with the foam added. For low density foamed concrete,the improvement of its ability to retain basement strength is the fundamental starting point of the strength optimization. Based on the above theory,adding fly ash to the foamed concrete to optimize the pore structure first,then introducing cement to the foamed concrete to reinforce the strength of the matrix. The compressive strength of the slag-based foam concrete,with 1800 m L foam volume（about 400 kg/m^3）,increase to 103%,its compressive strength increased from 1. 43 MPa to 2. 91 MPa.