Abstract: Based on the traditional prediction model of triangular fuzzy accident tree, which had the defect of large error caused by linear approximation, the source of error was analyzed according to the truncated set theorem, and the improved algorithm for drawing membership curve of triangular fuzzy number of accident treetop events was given according to the representation theorem. Matlab software was used to program, the modified and traditional triangle fuzzy accident prediction algorithms were used to predict the electrostatic accumulation accidents in oil depots, and calculated the fuzzy importance of 8 causes. According to the calculation results, compared with the traditional algorithm, the average error value of the fuzzy importance calculation of the eight basic events is reduced by 11.91%，which shows that the modified algorithm greatly optimizes the shortcomings of the traditional algorithm.

Key words: Triangular fuzzy number, Fault tree, Truncated set theorem, Representation theorem, MATLAB software

摘要： 基于传统三角模糊事故树预测模型存在因线性近似导致误差较大的不足，通过截集定理分析了误差的来源，根据表现定理给出了事故树顶上事件三角模糊数隶属度曲线绘制的改进算法。使用MATLAB软件编制程序，分别采用修正的和传统的三角模糊事故预测算法，针对油库静电积累事故进行预测，计算8个原因事件的模糊重要度。计算结果显示，与传统算法相比，修正算法8个基本事件的模糊重要度计算误差平均降低11.91%，表明修正算法极大地优化了传统算法的不足。

关键词: 三角模糊数, 事故树, 截集定理, 表现定理, MATLAB软件