Characteristics Of Magnesium Slag Composite Plaster

Plastering mortar is applied brushing played in building the base surface or leveling mortar to provide protection for a class collectively. Aiming at the problem of the low utilization rate of magnesium slag, plastering mortar widespread abscission and cracking quality problems. In order to improve the workability, strength properties of magnesium slag, drying shrinkage characteristics of the plastering mortar and solve practical engineering problems, explore ways to use magnesium slag, taking water binder ratio, magnesium slag content, fly ash replacement rate, unit water and admixture dosage as factors, orthogonal test scheme L25(56) is designed to study the workability, strength properties of magnesium slag and drying shrinkage characteristics of magnesium slag composite plaster mortar by experiment.Results show that water binder ratio, magnesium slag content, fly ash replacement rate, unit water and admixture dosage have varied influence on the workability, strength properties of magnesium slag and drying shrinkage characteristics of magnesium slag composite plaster mortar, and they are all can not be ignored as important factors. Magnesium slag has an adverse effect on the flow, the sink degrees and flow rate of the mortar. It helps solving the problem of shrinkage cracking of plastering mortar, there are some contribution of magnesium slag on the plastering mortar compressive strength and bond strength, and fly ash can significantly improve the bonding performance of plastering mortar. In the substitution rate of 30% fly ash, plaster mortar bond strength reaches a maximum. Plaster drying shrinkage strain increases with age increases, increases faster early, later increased slowly and gradually stabilized, and age showed good correlation hyperbolic relationship. Least squares method was used to build significant multiple nonlinear regression models of the workability, strength properties of magnesium slag and drying shrinkage characteristics of magnesium slag composite plaster mortar. Established multivariate nonlinear regression model correlation strength is good, with 95% confidence. Theoretical support is provided for the mixture ratio design and the workability, strength properties of magnesium slag and drying shrinkage characteristics improvement of composite plastering mortar.