可溶性P_(2)O_(5)对超细硫铝酸盐水泥基双液注浆材料早期水化性能的影响及机理

Effect and Mechanism of Soluble P_(2)O_(5)on the Early Hydration of Ultra-fine Sulfoaluminate Cement-based Double Liquid Grouting Materials

为了指导磷石膏在超细硫铝酸盐水泥基双液注浆材料(SCBGM)中的高效应用,研究了可溶性P_(2)O_(5)对大水灰比下SCBGM早期水化性能的影响及作用机理。结果表明,可溶性P_(2)O_(5)的加入不显著影响SCBGM浆体的凝结时间。可溶性P_(2)O_(5)掺量为0%~1.5%时,随着其掺量的增加,SCBGM早期强度逐渐增大。在1.5%最佳掺量下,可溶性P_(2)O_(5)可显著提高早期SCBGM中钙矾石的生成量,还可以显著优化硬化体中钙矾石的分布特征,使其由团簇状转变为显著的搭接交错分布状态,进而充分发挥钙矾石晶体的强度骨架效应。

In order to guide the efficient application of phosphogypsum in ultra-fine sulfoaluminate cement-based double liquid grouting materials(SCBGM),the effect of soluble P_(2)O_(5)on the early hydration performance of SCBGM at high water-cement ratio and its mechanism were studied.The results showed that the addition of soluble P_(2)O_(5)did not significantly affect the setting time of SCBGM slurry.When the soluble P_(2)O_(5)content was between 0%and 1.5%,the early strength of SCBGM increased with the increase of the soluble P_(2)O_(5)content.At the optimum dosage of 1.5%,soluble P_(2)O_(5)can significantly increase the amount of ettringite in early hydration of SCBGM,and also significantly optimize the distribution characteristics of ettringite in the hardened body,which changed from cluster shape to highly lapped staggered distribution,so as to achieve full potential of the strength skeleton effect of ettringite crystal.