两种高抗硫酸盐水泥稳定浆液性能对比试验研究

Experimental study on performance comparison of two kinds of high sulfate-resistant cement stabilized grout

摘要:

向家坝水电站坝基挠曲核部破碎带补强灌浆浆液采用高抗硫酸盐水泥浆液。灌浆孔深多超过150 m，钻灌施工过程中，其浆液稳定性、可灌性、固壁性、泌水性、初凝时间、结石体强度等，较常规工艺有更高的要求。为此，结合向家坝水电站坝基补强灌浆处理，现场开展了“掺加缓凝型减水剂的高抗硫酸盐水泥浆液”与“改性高抗硫酸盐水泥稳定浆液”对比试验研究。研究发现，采用六偏磷酸钠替代缓凝型高效减水剂作为缓凝剂与分散剂的改性高抗硫酸盐水泥稳定浆液稳定性、可灌性、固壁性、泌水性、初凝时间、结石体强度等性能均较掺加缓凝型减水剂的高抗硫酸盐水泥浆液更优，其性能与工艺的匹配性更好。

Abstract:

High sulfate-resistant cement grout was used for reinforcing the fractured zone in the flexural core of the dam foundation of Xiangjiaba Hydropower Station. Since the depth of grouting holes was more than 150m, higher requirements were specified for the grout than those used in the conventional process in terms of the stability, groutability, wall reinforcement, separation, initial setting time, strength of stone body, etc. during drilling and grouting construction. Therefore, research has been carried out to compare the high sulfate resistance cement added with the retarded water reducer and the modified the high sulfate resistance cementto deal with the reinforcement of the dam foundation of Xiangjiaba Hydropower Station with grouting treatment, and preliminary results have been achieved . It is found that the stability, groutability, wall reinforcement, separation, initial setting time and stone strength of the modified high sulfate-resistant cement slurry with sodium hexametaphosphate instead of the retarded superplasticizer as the retarder and dispersant are better than those of the high sulfate-resistant cement slurry with the retarded superplasticizer, and its performance is better matched with the process.