2.2 试验设计参数
öK§xy_În#bbs.3c3t.comÔ:â3iî̲设计试块90d 龄期无侧限抗压强度平均值不小于1.8MPa;
öK§xy_În#bbs.3c3t.comÔ:â3iî̲土样:淤泥质粘土;
öK§xy_În#bbs.3c3t.comÔ:â3iî̲水泥掺量:14%、17%、20%和23%;
öK§xy_În#bbs.3c3t.comÔ:â3iî̲水泥浆水灰比:0.50 和0(喷粉);
öK§xy_În#bbs.3c3t.comÔ:â3iî̲试验龄期:7d、14d、28d 和90d。
öK§xy_În#bbs.3c3t.comÔ:â3iî̲2.3 试验方法
öK§xy_În#bbs.3c3t.comÔ:â3iî̲试验方法参照规程《软土地基深层搅拌加固法技术规程》YBJ255-91 和《粉体喷搅法加固软
öK§xy_În#bbs.3c3t.comÔ:â3iî̲弱土层技术规程》TB10113-96 相关规定,试验用土样用5mm 筛筛去其中的夹杂物,拌合均匀,在
öK§xy_În#bbs.3c3t.comÔ:â3iî̲密封桶内,放置24h 后进行配合比试验。各种材料的用量按配合比准确称量,采用人工拌和,制
öK§xy_În#bbs.3c3t.comÔ:â3iî̲模后用塑料薄膜覆盖试件,以防水分蒸发过快。试件2d 后拆模,拆模后放置于温度为20±2℃的
öK§xy_În#bbs.3c3t.comÔ:â3iî̲水中养护至试验龄期。
öK§xy_În#bbs.3c3t.comÔ:â3iî̲3 试验结果及分析
öK§xy_În#bbs.3c3t.comÔ:â3iî̲水泥土7d、14d、28d 和90d 的无侧限抗压强度试验结果见表2,影响水泥土搅拌桩抗压强度的因
öK§xy_În#bbs.3c3t.comÔ:â3iî̲素包括:土样的性质、水泥掺量、水泥强度等级、水灰比、龄期等。
öK§xy_În#bbs.3c3t.comÔ:â3iî̲3.1 水泥掺量的影响
öK§xy_În#bbs.3c3t.comÔ:â3iî̲水灰比为0.50,水泥土试件无侧限抗压强度与水泥掺量的关系见图1,由图可见,两者呈线
öK§xy_În#bbs.3c3t.comÔ:â3iî̲性关系,相关性良好。水泥掺量从14%增加到23%时,7d 龄期无侧限抗压强度从0.50MPa 增大到
öK§xy_În#bbs.3c3t.comÔ:â3iî̲0.97MPa,增大94%;14d 龄期从0.61MPa 增大到1.43MPa,增大134.4%;28d 龄期从0.78 MPa 增
öK§xy_În#bbs.3c3t.comÔ:â3iî̲大到1.69MPa,增大116.7 %;90d 龄期从1.06 MPa 增大到2.29MPa,增大116.0 %。
öK§xy_În#bbs.3c3t.comÔ:â3iî̲水灰比为0(喷粉),水泥土试件无侧限抗压强度与水泥掺量的关系见图2,由图可见,两者呈
öK§xy_În#bbs.3c3t.comÔ:â3iî̲线性关系,相关性良好。水泥掺量从14%增加到23%时,7d 龄期无侧限抗压强度从0.76MPa 增大
öK§xy_În#bbs.3c3t.comÔ:â3iî̲到2.51MPa,增大230.3%;14d 龄期从1.15MPa 增大到3.1MPa,增大169.6%;28d 龄期从1.34MPa
öK§xy_În#bbs.3c3t.comÔ:â3iî̲增大到4.07MPa,增大203.7%;90d 龄期从1.74MPa 增大到5.42MPa,增大211.5%。详细见附件
öK§xy_În#bbs.3c3t.comÔ:â3iî̲附件:
水泥搅拌桩配合比设计试验方法.rar