盾构预拌砂浆运输中离析程度分析及优化

Analysis and optimization of segregation degree of shieldready-mixed mortar in transportation

由于盾构预拌砂浆在使用移动筒仓运输的过程中容易产生离析,因此,对已在实际生产中使用的盾构预拌砂浆在不同条件下的离析程度进行研究。在竖直振动模拟条件下,结合颗粒物质理论,以4种不同粒径的颗粒为材料,研究振动时长、砂粒径和分隔空间百分比等3种不同因素对离析程度的影响,用粗料含量变化来表征离析发生的规律,结果表明:振动时间超过60s时,离析程度显示为无明显变化的平缓曲线;粗颗粒粒径越大,分隔空间越大,离析程度越大。使用Design-expert11对试验结果进行综合分析,结果表明:各因素对盾构预拌砂浆离析指数的影响由大到小依次为振动时长、分隔空间百分比、砂粒径;当振动时长为180 s,砂粒径为0.3mm,分隔空间为25%时,离析程度最小,即为最佳方案。

As the segregation of shield ready-mixed mortar often occurs in the process of using moving silos for transportation,the segregation degree of shield ready-mixed mortar in actual use is studied under different conditions.Under the condition of vertical vibration simulation,combined with the particle matter theory,four kinds of particles with different particle sizes were used as materials to study the effect of three different factors,namely vibration duration,coarse particle size and separation space,on the segregation degree.The change of coarse material content was used to represent the law of segregation.When the vibration time was over 60 s,the segregation degree showed a gentle curve with no obvious change.The larger the size of coarse particles and the smaller the separation space,the greater the segregation degree.Design-expert 11 was used for comprehensive analysis.The results showed that the effect of the factors on segregation index of shield ready-mixed mortar in descending order was vibration duration,separation space and sand particle size;When the vibration duration was 180 s,sand particle size was 0.3 mm and the separation space was 25%,the segregation degree was the smallest,which was the best solution.