单壁螺纹PVC塑料套管现浇混凝土桩技术及现场试验

Single-wall corrugated PVC plastic tube-based cast-in-place concrete pile technology and field tests

介绍了单壁螺纹PVC塑料套管现浇混凝土桩(TC桩)的组成、特点、施工设备、施工流程及检测方法,结合申嘉湖杭高速公路练市至杭州段TC桩处理的软基工程,通过埋设土压力盒和钢筋应力计,比较分析了路堤荷载下桩帽顶上应力、桩帽间及桩帽下土应力的分布及变化规律,得出了桩土应力比、荷载分担比随填筑荷载的变化曲线。结果表明:随着填筑高度的增加,路堤荷载逐渐向TC桩转移,桩间土应力先增大后减小;在检测期内,TC桩的桩土应力比与荷载分担比始终趋于增大。

The composition, characteristics, construction equipment, construction process, and quality inspection method of cast-in-place concrete piles ( TC piles) , with single-wall corrugated PVC plastic tubes used in the construction process, are introduced. In combination with the soft foundation project of the Lianshi-Hangzhou section of the Shen-Jia-Hu-Hang Expressway reinforced by TC piles, the distribution and variation of the soil stress on the top of pile caps, and that between and under pile caps were compared and analyzed based on observations by embedded earth pressure cells and rebar stress meters. Variation curves of the pile-soil stress ratio and load sharing ratio against the filled load were obtained. The results show that the embankment load is gradually transferred to TC piles, and the pile-soil stress ratio increases first and then decreases as the height of embankment is increased. During the measurement period, the pile-soil stress ratio and load sharing ratio of TC piles tend to increase.