摘要
本着节能环保的发展理念，提出水泥粉煤灰建筑垃圾桩处理软土地基的方案，用建筑垃圾再生粗骨料（粒径范围4．75～9．5mm）代替碎石、细骨料（粒径范围0．075～0．6mm）代替中粗砂，并通过室内试验、现场试验及质量检测等验证方案的可行性。结果表明：建筑垃圾再生骨料混凝土的最佳配合设计为胶凝材料掺入比15％，水泥：粉煤灰=2：1（E组）；试件90d养护龄期的无侧限抗压强度较28d增加幅度在19．5％～26．5％之间，高于普通混凝土。采用标准试件28d养护龄期的无侧限抗压强度值作为再生骨料混凝土的抗压强度标准值，偏低；单桩复合地基的承载力为487．7kPa，较天然软土地基承栽力提高了3．8倍，满足复合地基承栽力的设计要求。
Based on the concept of energy saving and environmental protection, it is proposed to treat the soft soil foundation using cement fly-ash construction waste pile. The coarse aggregate （particle size： 4.75--9.5 mm） made from construction waste is used instead of gravel and fine aggregate （particle size： 0. 075--0.6mm） instead of medium coarse sand. The feasibility of the proposed scheme is verified through laboratory tests, field tests and quality inspection, etc. Re- sults show that a mixing ratio of 15% cementitious materials and a 2 ：1 cement to fly ash ratio （E group） is the optimum combination for the design of recycled aggregate concrete with con- struction wastes. The unconfined compressive strength of recycled aggregate concrete increases by 19.5%-26.5% after 90 days of curing compared with 28-day curing, which is higher than that of ordinary concrete. The unconfined compressive strength value with 28-day curing is used as the standard one for recycled aggregate concrete, which is relatively low. The bearing capacity of a single pile composite foundation reaches 487. 7 kPa, which is 3.8 times higher than that of a natural soft foundation, which can meet design requirements.
作者
鞠兴华
杨晓华
张莎莎
JU Xinghua;YANG Xiaohua;ZHANG Shasha(School of Highway,Chang＇an University,Xi＇an 710064,China)
出处
《防灾减灾工程学报》
CSCD
北大核心
2018年第4期723-730,共8页
Journal of Disaster Prevention and Mitigation Engineering
基金
国家自然科学基金项目(51209006)
陕西省教育厅专项科研项目(15JK1169)资助
关键词
软土地基
水泥粉煤灰建筑垃圾桩
室内试验
现场试验
地基承载力
soft soil foundation
cement fly-ash construction waste pile
laboratory test
field test
bearing capacity of foundation
