摘要
加固的桩头承载能力对静载试验成功与否至关重要,常规做法是采用混凝土进行桩头加固,但周期较长,且有时效果不好。统计表明,用混凝土加固的试验桩桩头,压爆数量占试桩总破坏数量的20%左右,基于此采用了高强灌浆料代替混凝土进行桩头加固。设计了水泥基高强灌浆料的配合比,制作了三组试块,轴心抗压强度试验结果表明,该材料短期强度发挥较快,1、3、7 d的平均抗压强度可以达到35.3、51.5、68.5 MPa。大量现场试验证明该材料加固混凝土试验桩在技术上是可行的,且具有很大的时间优势。针对不同承载力灌注桩,给出了桩头加固形式和龄期的建议。
The bearing capacity of the reinforced pile head is crucial to the success of the static load test.The conventional practice is to use concrete to reinforce the pile head,but the cycle is long,and sometimes the effect is not good.Statistics show that the number of test pile pile head reinforced with concrete accounts for about 20%of the total number of test pile damage.Based on this,high strength grouting material is used instead of concrete for pile head reinforcement.The mix ratio of cement-based high-strength grouting material was designed,and three groups of test blocks were made.The results of the axial compressive strength test show that the strength of this material is relatively fast in the short term,and the average compressive strength of 1d,3d and 7d can reach 35.3MPa,51.5MPa,68.5MPa.A large number of field tests have proved that strengthening the concrete test pile is technically feasible and has a great time advantage.The form and age of pile head reinforcement are suggested for different bearing capacity filling piles.
作者
郑贺
鲍宇
姚春磊
ZHENG He;BAO Yu;YAO Chunlei(Xuzhou Construction Engineering Management Center,Xuzhou Jiangsu 221018,China;Xuzhou City Construction Engineering Quality and Safety Supervision Station,Xuzhou Jiangsu 221116,China;Xuzhou Construction Engineering Testing Center Co.,Ltd.,Xuzhou Jiangsu 221000,China)
出处
《工程质量》
2024年第2期104-106,110,共4页
Construction Quality
关键词
桩头压爆
高强灌浆料
桩头加固
峰值割线模量
pile head pressure explosion
high strength grouting material
pile head reinforcement
peak cut-line modulus
