钻孔灌注桩是结构物常用的基础形式之一。特别是在沿海、河口及软弱地层地区,深而大的钻孔灌注桩往往是最佳的解决方案。近年来又出现了采用大直径单桩代替一些小的群桩支承巨大荷载的趋势,因此,上部结构的可行性就取决于每根桩的性状和承载力。要达到保证每根桩都能支承其设计荷载的目的,除了预防机械故障、操作失误,加强施工管理以外,如何控制水下混凝土的质量,并对做好完成的每一根基桩进行质量鉴定,则是保证钻孔灌注桩正常工作的根本。下面,谈一下对这个问题的看法,并对国内目前采用的机械阻抗法、超声波检测法等质量鉴定方法作一介绍。 Drilled cast-in-place piles are one of the basic forms of structures commonly used. Especially in coastal areas, estuaries and weak formations, deep and large bored piles are often the best solution. In recent years, there has been a trend of using large diameter single piles instead of some small group piles to support huge loads. Therefore, the feasibility of the upper structure depends on the properties and bearing capacity of each pile. To achieve the purpose of ensuring that each pile can support its design load, in addition to preventing mechanical failures and operational mistakes, and strengthening construction management, how to control the quality of underwater concrete and perform quality appraisal on each pile completed It is the fundamental guarantee for the normal work of bored piles. Below, talk about the views on this issue, and introduce the current domestic methods of mechanical impedance, ultrasonic testing and other quality assessment methods.