预埋注浆管堵塞事故及其处理方法的研究

 通过浙江省一工地工程桩由于预埋注浆管无法打开而无法完成注浆的事故，阐述预埋注浆管注浆方案，桩身混凝土中心钻孔补注浆方案和桩侧土钻孔补注浆方案的具体施工措施，得到不同注浆方案中注浆压力和注浆量随时间的变化规律。在桩身混凝土中心钻孔补注浆方案中，可利用橡胶止浆塞封堵高压浆液来完成补注浆工作。在桩侧土钻孔补注浆方案中，可采用橡胶止浆塞和止水膨胀带相结合的止浆工艺及间歇注浆方式来完成补注浆工作。

STUDY OF BLOCKAGE ACCIDENT OF PRE-EMBEDMENT GROUTING PIPES AND ITS CORRESPONDING TREATMENT METHOD

This paper presents an accident caused by unopened pre-embedded grouting pipes of working piles at a site of Zhejiang Province，and then proposes construction measures of post-grouting conducted using two pre-embedded grouting piles，a borehole drilled in pile shaft and a hole embedded in soil around pile. The variation of grouting pressure and grouting amount with time during different schemes of post-grouting was also discussed. In the scheme of post-grouting conducted using a borehole drilled in pile shaft，rubber packer can be used to avoid cement sully leakage，while rubber packer and swelling water-stopper can be adopted to prevent cement sully leakage，as well as intermittent grouting technique being employed，in the scheme of post-grouting conducted with a borehole embedded in soil around pile.