建筑垃圾掺量变化对制备自流平地坪砂浆性能的影响

Construction waste content change on the influence of the preparation of self-leveling floor

将建筑垃圾各部位(板、柱和砖)按质量比1∶1∶1混合后成建筑垃圾砂,按照不同比例10%、20%、30%、40%和50%的掺量替代天然砂,并测试混合后再生垃圾砂的表观密度和空隙率;随后与胶凝材料和添加剂混合制备自流平地坪砂浆,按JCT 985—2005《地面用水泥基自流平砂浆》要求测试流动度、抗压强度、抗折强度、吸水率。试验表明:混合后再生垃圾砂表观密度基本在1 500 gL,空隙率随建筑垃圾砂掺量增加而增大,掺量50%时,达到最大35%;砂浆流动度随建筑垃圾砂掺量增加先增大后减小,掺量为30%时,达到最大110 mm;建筑垃圾砂掺量为50%时,砂浆90 d抗压与抗折强度达到最大分别是48.1、6.5 MPa;砂浆吸水率随建筑垃圾砂掺量增加先增大后减小,掺量为40%时,达到最大10.8%。

Various parts of the construction waste（ plates,columns and bricks） were prepared to construction waste sand by mixing mass ratio of 1 ∶ 1 ∶ 1. Then according to different proportions of construction waste sand which were 10%,20%,30%,40%and 50%replaced natural sand. And apparent density and porosity of the regeneration of mixed waste sand were tested. The regeneration of waste sand and cementitious materials and additives were mixed to prepare self-leveling flooring mortar,according to JC/T 985—2005 ＂Cementitious self-leveling floor mortar＂,it required to test fluidity,compressive strength,flexural strength,water absorption. Experimental results showthat： the apparent density of regeneration of waste sandis 1 500 g/L basically,with the contentsof construction waste sandincrease,the porosities increase. When content is 50%,the porosityreach a maximum of 35%; With contentsof construction waste sand increase,mortar fluidityincreases firstly and then decreases,when content is 30%,the fluidityreach a maximum 110 mm; construction waste sand content is 50%,the 90 days of mortar compressive and flexural strength reach the maximumwhich are 48.1 M Pa and 6.5 M Pa; With the contentsof construction waste sandincrease,mortar absorption increase firstly and then decrease. When content is 40%,the absorption reach a maximum of 10.8%.