单钻孔灌注桩桩底注浆承载性状对比试验

介绍了试验的场地条件、试验桩的设计、桩底注浆参数及其检测。研究了持力层为砂卵石层单钻孔灌注桩桩底注浆承载性状,并且综合对比分析了桩端阻力和桩侧阻力的特性。通过对比试验,发现注浆后单桩极限承载力显著提高,平均增幅大约为27%,沉降量显著减少,平均减幅大约为66%,但回弹率呈上升趋势,平均增幅大约为42%。另外,桩端阻力也有较大幅度的提高,桩身上部侧阻力影响不明显,而对桩身下部特别在桩端周围侧阻力影响较显著。

Contrast Test on Load Bearing Behavior of Single Bored Piles Grouted at the Bottom of the Pile

The contrast test includes the site condition design of pile and grouting parameters.The load bearing behavior of single bored piles grouted at the bottom of pile with sand and stone layers is researched.The characteristics of tip resistance and side friction of pile are analyzed.In contrast test,the ultimate bearing capacities of single pile increase about 27%.And the settlement of single pile reduces about 66%.But the rebounding ratio increases about 42%.Moreover,the tip resistance of the pile presents significant rise.The influence about the side friction of upper part of pile is not obvious,but influences the tip and lower part of the pile.