新型粉煤灰用于干混粘结砂浆的实验研究

Experimental study of special fly ash used for dry-mixed adhesive mortar

研究了经旋风分离的粉煤灰取代水泥以及不同可再分散乳胶粉对粘结砂浆性能的影响。结果表明:使用经过旋风分离处理的粉煤灰可取代水泥的最大比例为70%;粘结砂浆的14 d拉伸粘结原强度主要是由可再分散乳胶粉提供,而(14+7)d耐水粘结强度主要是由水泥来提供;使用不同可再分散乳胶粉对粘结强度有影响,当粉煤灰取代水泥的比例不高于50%时,使用2种不同胶粉的粘结砂浆粘结强度都能符合JG/T 149—2003标准要求,但粉煤灰可取代水泥的最大比例相差很显著,约为20%。

This study is to report the use of a unique fly ash to replace cement under different types of latex powders on the adhesive mortar performance. Experimental data show that this fly ash can replace cement up to 70%,while the other fly ash cannot. Further comparison with the data for cement completely replaced by fly ash, 14-day adhesive strength is mainly provided by redispersible powders,while 14＋7 days water-resistant adhesive strength is mainly provided by cement. Different redispersible pow- ders can have the effects on the adhesive strength; when not high than 50% of cement is replaced by this fly ash,mortars using both powders meet the JG/T 149--2003 standard requirements. However,the difference in the maximum cement replacement is sig- nificant,about 20%.