石膏基复合胶凝材料的配比优化试验

OPTIMIZED MIX PROPORTION OF GYPSUM-BASED COMPOSITE CEMENTITIOUS MATERIALS

以煅烧工业副产石膏为基材,混掺矿物掺合料和改性外加剂,通过设计正交试验研究石膏基复合材料中胶凝材料各组分掺比及水胶比对其力学性能和耐水性的影响,试验结果表明,固废胶结材与活性胶结材质量比是影响石膏基复合胶凝材料吸水率最主要因素,水胶比是影响其干密度和强度的最主要因素;当脱硫石膏、粉煤灰、矿粉、水泥、生石灰的配比为1:0.53:0.13:0.5:0.05时综合性能良好;建筑脱硫石膏水化形成的二水石膏晶体结构,与水泥、粉煤灰等水化形成的钙矾石和C-S-H凝胶等水硬性产物相互搭接成密实结构,显著提升了石膏基复合胶凝材料的强度和耐水性能。

In this paper, the calcined industrial by-product gypsum was used as the base material to mix with mineral admixture and modified admixture. In the orthogonal testing scheme, the mixing ratio of each component of cementitious material, the ratio of water-to-binder ratio to the mechanical, and water resistance of gypsum-based composites were studied. The results show that the mass ratio of solid waste rubber to active cement is the most important factor affecting the water absorption of gypsum matrix composites. The water-to-binder ratio has the most important effect on the dry density and strength. Moreover, when the ratio of desulfurization gypsum powder, coal ash, mineral powder, cement and quicklime is 1:0.53:0.13:0.5:0.05, the comprehensive performance is better. Furthermore, the crystal structure of dihydrate gypsum formed by hydration of building desulfurization gypsum and the hydraulic products formed through the hydration of cement and fly ash such as ettringite and CSH gel are lapped to form a dense structure which significantly improves the strength and water resistance of the gypsum-based composite cementitious material.