外加剂掺量对常温型套筒灌浆料性能的影响

Influence of Admixture Dosage on the Performance of Normal Temperature Type Cementitious Grout for Sleeve

为探讨外加剂对常温型套筒灌浆料性能的影响,对市售的减水剂、缓凝剂和早强剂进行初步筛选,筛出性能较佳的产品进一步探究。研究减水剂、缓凝剂和早强剂掺量对常温型套筒灌浆料初始流动度、0.5 h流动度、3 h及24 h竖向膨胀率、1 d强度的影响。结果表明:灌浆料的流动度随着减水剂掺量提高而增大,3 h竖向膨胀率减小,其3 h与24 h竖向膨胀率之差增大,最佳掺量为0.7%~0.8%;灌浆料的3 h及24 h竖向膨胀率随着早强剂掺量的提高而增大,早期强度增大,流动度减小,最佳掺量为0.3%;灌浆料30 min流动度随缓凝剂掺量的提高而增大,3 h与24 h的竖向膨胀率减小,在掺量≯0.2%时,提高灌浆料3 h与24 h的竖向膨胀率之差,掺量>0.2%时,灌浆料的早强降低,缓凝剂最佳掺量为0.2%。

In order to investigate the effect of admixture on the performance of normal temperature type sleeve grouting material,the commercial water reducing agent,retarding agent and early strengthening agent were preliminly screened,and the products with better performance were screened out for further exploration.The effects of water reducing agent,retarder and early strength agent dosage on initial fluidity,0.5 h fluidity,3 h and 24 h vertical expansion rate and 1 d strength of room temperature type casing grouting were studied.The results showed that the fluidity of cementitious grout increases with increasing the dosage of water reducer,the 3 h vertical expansion rate decreases,and the difference between 3 h and 24 h vertical expansion rates increases.The optimum content is 0.7%~0.8%.The 3 h and 24 h vertical expansion rate of cementitious grout increases with increasing the dosage of early strength agent,the early strength increases,and the fluidity decreases,the optimum content is 0.3%.The 30 min fluidity of cementitious grout increases with increasing the dosage of retarder,and the 3 h and 24 h vertical expansion rate decreases.When the dosage is not more than 0.2%,the difference between 3 h and 24 h vertical expansion rate increases,while the dosage is greater than 0.2%,the early strength of the grouting material decreases,and the optimal dosage of retarder is 0.2%.