凝灰岩石粉对机制砂饰面砂浆性能的影响研究

Study on the effect of tuff rock powder on the properties of machine-made sand facing mortar

为明确凝灰岩石粉在机制砂饰面砂浆中应用的可行性,采用石粉替代部分水泥制备机制砂饰面砂浆,研究了石粉掺量(0、5%、10%、15%和20%)对饰面砂浆力学性能、吸水量、泛碱面积及微观形貌的影响规律。结果表明:石粉掺量为0~15%时,饰面砂浆力学性能随石粉掺量的增大而减小,而当石粉掺量增大为15%~20%时,力学性能略有提升;石粉的掺入不利于饰面砂浆吸水量的控制,而有助于抑制饰面砂浆的泛碱行为,当石粉掺量为20%时,初次泛碱和二次泛碱的面积分别可降低37.9%和58.3%;利用凝灰岩石粉部分替代水泥制备饰面砂浆具有较好的适用性,其掺量应控制在10%~15%为宜。

In order to clarify the feasibility of the application of tuff rock powder in machine-made sand facing mortar,it uses stone powder to replace part of cement to prepare machine-made sand facingmortar.The effects of the content of stone powder(0,5%,10%,15%and 20%)on the mechanical properties,water absorption,alkali pan area and micro morphology of facing mortar were studied.The results show that when the content of stone powder is from 0 to 15%,the mechanical properties of facing mortar decrease with the increase of the content of stone powder,while when the content of stone powder is from 15%to 20%,the mechanical properties improve slightly.The addition of stone powder is not conducive to the control of water absorption of facing mortar,but helps to inhibit the alkali flashing behavior of facing mortar.When the content of stone powder is 20%,the area of primary alkali flashing and secondary alkali flashing can be reduced by 37.9%and 58.3%respectively.The use of tuff rock powder to partially replace cement to prepare facing mortar has good applicability,and its dosage range should be controlled from 10%to 15%.