【摘要】 国内某桥梁工程水下钻孔桩设计桩长55 m,桩径1.8 m。经超声检测判定,桩身48.8~49.4 m处出现严重缺陷,为Ⅳ类桩。按规定应予以凿除,但现场情况难以满足凿桩条件。经过分析决定先钻芯至桩身异常位置,再采用高压水流和气举法使缺陷段形成"空体",最后压密注浆对缺陷段进行补强。通过处理前后声波检测图对比和单桩承载力计算,验证该方法是可行的。更多还原

【Abstract】 The underwater bored pile used in a domestic bridge engineering is of 55 m in length and 1. 8 m in diameter. One of those is determined to be class Ⅳ as serious flaws appear at 48. 8 ~ 49. 4 m,according to the ultrasonic testing result. In compliance with specification requirement,the pile should be abandoned,but the reality is difficult to achieve. In situ test study shows,core-drill method can be adopted to find the abnormal region of pile where a"empty part"is created using high-pressure water and gas lift method,then reinforcing work can be performed by pressure grouting when processes mentioned above have been conducted. This method has been validated through contrast analysis of ultrasonic testing and single pile bearing capacity calculation.更多还原