输电工程中后注浆灌注桩的试验研究及应用

The experimental study and application of PPG pile in transmission line

后注浆桩作为2008版桩基规范推荐的一种新型桩基础型式,具有可靠性高、承载力增幅大、经济效益显著等特点。由于缺少参数,无法在输电线路工程中直接采用。通过后注浆抗拔、受水平作用的真型试验,得到了计算公式和计算参数,并对试验的过程进行了描述。试验数据表明对于输电线路以抗拔受力为主的条件下,后注浆桩比普通桩承载力可以提高30%-50%,造价可节省15%-35%,具有广阔的推广应用前景。对受压、抗拔、受水平作用下的参数进行了推荐,方便以后工程中的应用。

Recommended as a new type of pile foundation by building specification published in 2008, pile post grounding （PPG） pile has characteristics of high reliability, large bearing capacity increase and economic efficiency. However, it is not used widely in transmission line building due to lack of related parameters. The PPG pile field pulling and horizontal bearing test were described in detail in order to get calculation formula and parameters. Experimental data show that PPG pile can improve bearing capacity by 30%-50% and reduce construction cost by 15%-35% compared with common pile under condition mainly dominated by uplift force. Parameters under various conditions, including bearing pressure, uplift and horizontal affect, are recommended to facilitate later project application.