Lightweight Polymer Dry Powder Mortar Compressive Strength and Frost Resistance
As the outer surface layer of a building,the exterior wall plastering mortar is affected by frost damage all year round,in order to effectively alleviate frost damage and clarify the deterioration mechanism.In this study,fine aggregate,such as hollow floating bead,was utilized.Heavy calcium and polymer dry powder were mixed with cement to prepare light plaster with different water-cement ratios.Through orthogonal test,the effects of water-cement ratio,content of redispersible polymer powder,and heavy calcium content on compressive strength and frost resistance were revealed.And the microscopic mechanism of mortar performance change was dis-cussed.The results show that the water-cement ratio has a significant effect on compressive strength,followed by the amount of redis-persible polymer powder.And the effect of heavy calcium content is the least significant.Regarding antifreeze performance,the quanti-ty of redispersible polymer powder has a significant impact,and the quantity of heavy calcium has the least impact.At different curing stages,the water-cement ratio has a greater influence on compressive strength,and the amount of redispersible polymer powder has a greater effect on the anti-freezing performance.If the water-cement ratio is maintained around 0.35,the contents of redispersible poly-mer powder and heavy calcium are limited to 3%.Although the compressive strength is slightly reduced,the frost resistance is excel-lent.Considering the actual needs of compressive strength and frost resistance,the frost resistance of exterior wall plastering mortar is of greater importance than compressive strength.Based on this,it can be concluded that the optimal ratio for dry powder plastering is 0.37 water-cement ratio,2.8%redispersible polymer powder content,and 3.9%heavy calcium content.Additionally,in combination with the actual working environment and engineering requirements,dry powder plasters with different proportions can be designed.