试验方法对铁路喷射混凝土用液体速凝剂检验的影响

The Inf luences of Test Methods on the Inspections of Liquid Flash Setting Admixtures for Railway Shotcrete

GB/T 35159-2017 《喷射混凝土用速凝剂》于2018年11月1日开始实施,与JC 477-2005《喷射混凝土用速凝剂》相比,新标准在检验项目、试验方法上均有变化,并提高了后期强度损失、有害物质含量的指标。本文选择不同厂家、不同类型液体速凝剂,依据新旧标准检验掺液体速凝剂净浆及砂浆性能。结果表明:依据GB/T 35159-2017检验,检验结果重复性明显改善,净浆性能检验结果均低于依据JC 477-2005检验的结果,砂浆性能检验结果均高于依据JC 477-2005检验的结果。但依据GB/T 35159-2017判定,无碱液体速凝剂检验结果合格率会降低,有碱液体速凝剂检验结果合格率会升高。

GB/T 35159-2017 Flash setting admixtures for shotcrete was implemented on November 1,2018.Compared with JC 477-2005 Flash setting admixtures for shotcrete ,the new standard has changed in inspection items and test methods,and improved the indicators of late strength loss and harmful substance content.In this paper,liquid f lash setting admixtures from different manufacturers and with different types were selected to test the performances of paste and mortar mixed with liquid f lash setting admixtures according to new and old standards.The results show that according to the GB/T 35159-2017 test,the repeatability of the test results is signif icantly improved and the test results of the paste performances are lower than those based on J C 477-2005 test,the test results of mortar performances are higher than those based on J C 477-2005.However,according to GB/T 35159-2017,the qualif ied rate of alkali-free liquid f lash setting admixtures test results will be reduced,while the qualif ied rate of alkali liquid f lash setting admixtures test results will be increased.