中等强度等级自密实混凝土的工程应用与质量控制技术研究

Application technology and quality control of medium strength self-compacting concrete

基于试验研究结果,于工程现场成功配制了C30掺聚丙烯纤维自密实混凝土,并顺利完成了33.6 m长的密集配筋梁的现浇施工。结果表明：分批次各随机测试相应新拌自密实混凝土坍落度和坍落扩展度的变异系数在12%以内 现场成型试件28 d龄期时的抗压强度标准差在3~4 MPa之间,达到了设计强度等级要求 施工后的梁体拆模后表面质量良好,梁底及两侧混凝土均未发现可见裂纹等缺陷。在现场搅拌工艺条件下,该工程自密实混凝土质量得到了较好的控制。

The 30 MPa compressive strength self-compacting concrete with pp fiber was successfully prepared in job-site.And then several heavy reinforcement beams with 33.6 meter long were cast in practice.Results indicate the variable coefficient of slump and flow-spread of flesh concrete can be controlled within 12 percent in jobsite condition.Standard difference of compressive strength of samples cast in jobsite at 28 d ages ranges from 3-4 MPa.The surface quality of concrete beams is good and no voids or cracks in bottom or lateral of beam was observed when demolded. The quality of medium compressive strength self-compacting concrete can be controlled well under job-site condition.