1设计取值偏保守桩基工程的单桩承载力一般按试验值求得，然后据以进行桩点布置设计。在以往的工程中，为了加快设计进度，无论是预制桩还是灌注桩，一般在试验桩施工半个月，就作承载力动测试压，这时所得承载力数值往往偏低，致使设计安全系数偏高，造成不应有的浪费。2桩的 1 The bearing capacity of a single pile with conservatively designed pile foundation is generally determined according to the experimental value, and then the design of the pile point layout is carried out. In previous projects, in order to speed up the design progress, no matter whether it is a prefabricated pile or a cast-in-place pile, it usually takes half a month before the test pile is constructed to carry out the bearing dynamic test pressure. At this time, the obtained bearing capacity value is often low, resulting in a design safety factor. High, causing undue waste. 2 piles