[提要]  为克服传统确定桩筏筏厚方法的弊端，提出按两种极限状态计算筏厚的方法以及在正常使用极限状态下影响筏厚的基本因素。在此基础上，提出了一种按正常使用极限状态确定筏厚的简明算法。
[关键词]  正常使用极限状态 桩筏基础 筏板 厚度

Overcoming shortage to determine the raft thickness in pile-raft foundation traditionally, the author pro-poses a method that the raft thickness is determined according to two kinds of limit state and the fun-
damantal factor influencing raft thickness in serviceabilty limit state. A simple calcalation method for deternuned raft thickness is proposed according to serviceability limit state.
Keywords: serviccability; pile-raft  foundation; raft; thickness