混凝土搅拌二次投料法,也称先拌水泥砂浆法,是在不增加水泥用量的情况下,通过改变投料程序,一开始就使水泥颗粒充分分散并包裹在砂子表面,避免产生小水泥团,充分发挥水泥的物性,以提高强度的方法。通常采用的一次投料法,水泥颗粒被砂石夹裹着进入搅拌机内,遇水后很快成为小水泥团粒,水灰比越小,这种结块现象越严重。这种团粒附在粗骨料上,骨料的粒径越大,水泥团拉越不易破坏。在搅拌机内搅拌时,由于摩擦和撞击的作用,处于骨料运动方向背面的水泥团粒被有效地保护起来,粒径大于水泥团粒几倍至几十倍的粗骨料成了 The concrete mixing secondary feeding method, also known as cement mortar mixing method, is to change the feeding procedure without increasing the amount of cement. The cement particles are fully dispersed and wrapped on the sand surface to avoid the formation of small cement aggregates. Give full play to the physical properties of cement to increase strength. The one-time feeding method usually used is that the cement particles are trapped in the sand by the sandstone and enter the mixer. The water will soon become a small cement pellet. The smaller the water-cement ratio is, the more serious the agglomeration phenomenon will be. This pellet is attached to the coarse aggregate. The larger the aggregate size, the more difficult it is to pull the cement pellet. When stirring in the mixer, due to friction and impact, cement granules in the direction of the movement of the aggregate are effectively protected. The coarse aggregate with grain sizes of several to several tens of times larger than cement aggregates is formed.