桩基础设计时应结合场地地质条件、上部结构特征、场区周围环境、静载试验结果以及工期等因素综合分析,合理确定其单桩承载力、桩径和桩长.本文介绍泥浆护壁钻孔灌注桩设计中,利用反循环清孔,控制清孔到灌注砼的时间差以检测泥皮厚度和总成孔时间等因素来进行控制. The design of pile foundation should be combined with site geological conditions, superstructure characteristics, surrounding environment of the field area, static load test results and duration, etc. to determine the bearing capacity, pile diameter and pile length of a single pile reasonably. This paper describes the mud wall protection drilling. In the design of cast-in-situ piles, the use of counter-recirculation cleaning, controlling the time difference between the cleaning and pouring of the infusion crucible to detect the thickness of the clay skin and the assembly time and other factors to control.