發(fā)布時(shí)間：2018-11-19 13:40

【摘要】：水泥基飾面砂漿表面通常會(huì)形成由碳酸鈣結(jié)晶形成的白色泛堿現(xiàn)象。泛堿嚴(yán)重影響水泥基飾面砂漿的觀感裝飾效果,制約了水泥基飾面砂漿的大規(guī)模推廣應(yīng)用。目前對泛堿程度的表征方法缺少共識,影響泛堿的因素研究不夠深入,缺少有效的抑制泛堿的措施。本文研究了飾面砂漿泛堿程度表征方法,定量分析各因素對飾面砂漿泛堿程度的影響并采用針對性措施抑制飾面砂漿泛堿,研究結(jié)果表明:①基于圖像灰度處理技術(shù),可以區(qū)分具有不同灰度值的顏色對砂漿泛堿程度的影響。函數(shù)=∑r×=255=+15可以較好的表征飾面砂漿泛堿程度,其計(jì)算值與實(shí)際評價(jià)值具有很好的相符性。②隨水化生成的Ca(OH)2含量增加泛堿程度成倍提高,Ca(OH)2含量為3.22%是砂漿早期不泛堿的安全值,Ca(OH)2含量為4.82%是砂漿后期期不泛堿的安全值;開口孔隙率的大小對砂漿泛堿程度具有決定性的作用,增大孔隙率會(huì)加劇飾面砂漿泛堿,初次泛堿程度與同齡期開口孔隙率具有:Y=2.7016x-35.04976的關(guān)系,二次泛堿程度與同齡期開口孔隙率關(guān)系為:Y=3.4432x-9.47778;改善砂漿表面潤濕性增大其接觸角,可促進(jìn)砂漿表面向憎水性轉(zhuǎn)變,改善其抗?jié)B性有效防止外部水分進(jìn)入砂漿內(nèi)部,經(jīng)憎水劑乳液外涂的砂漿1d和7d齡期的砂漿泛堿程度僅為16.0和5.4,有效的抑制了砂漿二次泛堿;溫度、濕度和風(fēng)速等環(huán)境因素的變化都不同程度的改變了砂漿泛堿的程度,其中砂漿泛堿程度對濕度的變化最敏感,溫度變化次之,風(fēng)速變化對砂漿泛堿程度的影響最小。③可再分散乳膠粉和纖維素醚均可以降低砂漿吸水率,它們在砂漿中與Ca2+、Na+和K+等堿離子形成絡(luò)合物阻礙了孔溶液中堿性離子的遷移,從而有效降低砂漿的泛堿程度,且兩種聚合物復(fù)摻時(shí)具有較好的協(xié)同作用;消泡劑使得砂漿更加密實(shí),減少了內(nèi)部游離堿離子往外遷移的通道,具有明顯的抑制泛堿作用,摻加0.05%-0.15%的消泡劑可以使砂漿泛堿程度控制在30.0以內(nèi),但由于摻加消泡劑不能完全阻塞水分滲透的通道,抑制泛堿效果并不理想;摻加惰性填料并不能有效抑制飾面砂漿泛堿,摻量超過10%還存在加劇砂漿泛堿的風(fēng)險(xiǎn),在較低摻量下偏高嶺土即可消耗大量的Ca(OH)2,抑制泛堿效果顯著;憎水劑內(nèi)摻和外涂均可促進(jìn)砂漿表面向憎水性轉(zhuǎn)變,使得外部水分更難進(jìn)入砂漿內(nèi)部,進(jìn)而減輕砂漿的泛堿程度,憎水劑Qg摻不如外涂時(shí)抑制砂漿泛堿的效果理想。
[Abstract]:The white ubiquitin phenomenon formed by calcium carbonate crystallization is usually formed on the surface of cement-based finishing mortar. Pan-alkali seriously affects the decorative effect of cement based decorative mortar, which restricts the large-scale application of cement based decorative mortar. At present, there is a lack of consensus on the characterization methods of ubiquitin degree, the factors affecting pan-alkali are not deep enough, and the effective measures to inhibit pan-alkali are lacking. In this paper, the method of characterizing the degree of ubiquitin of finishing mortar is studied, the influence of various factors on the degree of ubiquitin of finishing mortar is quantitatively analyzed, and the corresponding measures are adopted to restrain the ubiquitin of finishing mortar. The results show that: 1 based on the technique of image grayscale processing, The effect of color with different gray values on the degree of ubiquitin of mortar can be distinguished. The function = 鈭，

本文編號：2342468