1 水下灌注砼的性能参数1.1 砼原料为确保成桩质量,要严格检查验收进场原材料的质保书(水泥出厂合格证、化验报告、砂石化验报告),如发现实样与质保书不符,应立即取样进行复查,对不合格的材料严禁用于砼灌注桩。粗骨料宜选用卵石,石子含泥量<2%。1.2 砼搅拌方法和搅拌时间为使砼具有良好的保水性和流动性,应按合理的配合比将 1 Underwater perfusion of concrete performance parameters 1.1 Concrete raw materials In order to ensure the quality of the pile into, we must strictly check the acceptance of incoming raw materials warranty book (cement factory certificate, laboratory report, sand test report), if found to be inconsistent with the warranty book , Should be immediately sampled for review, the unqualified material is prohibited for concrete bored pile. Coarse aggregate should choose pebbles, pebbles with mud content <2%. 1.2 Concrete mixing method and mixing time To make concrete has good water retention and fluidity, should be a reasonable mix of