中文摘要：

为提高塑料套管混凝土桩（简称TC桩）的承载性能,结合桩侧注浆技术,发展和形成了塑料套管管侧前注浆桩（简称TCSG桩）。通过现场试验,对TCSG桩、TC桩和扩径塑料套管混凝土桩（简称TCLD桩）3种桩型在不同时期进行了静载试验,并引入了3种易于应用的单桩沉降计算模型对各桩体的沉降进行了计算。试验结果和沉降模型计算分析表明：与TC桩相比,TCSG桩增加了8.3%~20.0%的承载力,并减小了19.8%~33.5%的沉降,而TCLD桩降低了10.0%~16.7%的承载力,且增加了13.2%~43.8%桩体的沉降;TCSG桩的轴力衰减速率大于TC和扩径的TCLD桩的,TCSG桩的前、后期的平均轴力衰减速率相差不大,TC桩后期的平均轴力衰减速率相比前期提高了1.1%~14.2%,而TCLD桩却降低了5.9%~21.9%;在前、后期静载时,TCSG桩在各级荷载下的平均单位侧摩阻力相比TC桩分别提高了14.5%~39.6%和9.2%~28.6%,扩径后的TCLD桩则分别降低了4.9%~11.8%和11.5%~30.7%;管侧前注浆后的TCSG桩的时效特性不显著,扩径后的TCLD桩的侧摩阻力随时间减小而端阻力则增大;基于桩土荷载传递的单桩沉降计算模型能够较好地预测塑料套管桩的沉降。

英文摘要：

To enhance the beating capacity of plastic tube cast-in-place concrete pile （TC pile）, the plastic tube cast-in-place concrete pile with shaft pre-grouting （TCSG pile） was developed in combination with the technology of shaft grouting. The in-situ static load tests were carried out on the TCSG pile, TC pile, and plastic tube cast-in-place concrete pile with large diameter （TCLD pile） installed in different times. Meanwhile, three kinds of calculation models of single pile settlement were introduced to predict the piles settlement. The testing and calculating results indicate that the bearing capacity of TCSG pile is raised by 8.3%-20.0% with a settlement decreased by 19.8%-33.5%; while the bearing capacity of TCLD pile is reduced by 10.0%-16.7% with a settlement increased by 13.2%-43.8%; compared with TC pile; the ratio of axial force attenuation of TCSG pile is greater than that of TC pile or TCLD pile; the difference is trivial between the average ratios of axial force attenuation for TCSG pile respectively obtained in earlier and later static load tests; the average ratio of axial force attenuation of TC pile gained in the later static load test is increased by 1.1%-14.2% compared with that in earlier static load test; while a reduction of 5.9%-21.9% in the average ratio of axial force attenuation is found in TCLD pile; the average skin frictions of TCSG pile under each loading level, compared with TC pile, increase by 14.5%-39.6% and 9.2%-28.6% during the earlier and later static load tests, respectively; while those of TCLD pile decrease by 4.9%-11.8% and 11.5%-30.7% due to enlarging the diameter of TCLD pile; the increasing of bearing capacity of TCSG pile with time is insignificant; the skin friction of TCLD pile diminishes with time elapsing; in contrast, the end resistance of TCLD pile increases; the calculation model of single pile settlement based on the pile-soil load transfer can well predict the settlement of a single plastic tube pile.