为充填原位弃置的输油管道,以粉煤灰为主并掺入少量水泥,加入聚羧酸系高性能减水剂、保坍剂和增稠剂等外加剂,研制一种可控低强度材料(CLSM)。采取正交试验,进行极差分析、方差分析以及统计综合分析,优化充填材料的配合比。利用数学统计变异系数法赋予充填材料的流动性能、泌水率和强度等3个参数在配合比设计中的权重,采用功效函数方法将各参数统一为无量纲的指标,根据计算得到的指标值评价材料的工作性能。实验结果表明:在该优化配合比条件下,CLSM充填材料28 d抗压强度可达到2.60 MPa,4 h流动度达250 mm,4 h泌水率4.2%,较好的满足废弃输油管道充填材料性能指标要求。统计综合分析能精确直观地评价充填材料的性能指标,可作为充填材料配合比优化的有利手段。研究成果对可控低强度材料在废弃输油管道充填工程中的应用具有重要意义。
Using fly ash as the main raw material with a certain amount of cement, polycarboxylate super plasticizer and the admixture such as slump retaining agent and thickening agent, a type of controlled low-strength materials (CLSM) is developed that can be used to fill the discarded oil pipeline. For optimization of the mix proportioning of the filling material, the orthogonal experiment was adopted, and the range analysis, variance analysis and comprehensive statistical analysis of acquired results were performed. Mathematical statistical variation coefficient method was used to entrust with the weight to the flow of the filling material performance, bleeding rate and the intensity of three parameters, adopting efficacy function method to uniform the parameters for the dimensionless indicators, to evaluate the performance of materials according to the calculated indexes. When mix proportions were optimized, optimal comprehensive strength at 28 d was nearly 2.60 MPa, while 4 h fluidity and 4 h bleeding rate were 250 mm and 4. 2%, which sufficiently meets the performance requirements of pipeline-filling material. The results show that comprehensive statistical analysis can be used to evaluate the comprehensive performance of the filling material accurately and intuitively as a new route to the design and choice of CLSM mix proportions.