平台巴西圆盘(CFBD)具有避免加载点处应力集中、保证破坏由预制裂纹尖端处起始的优点，成为研究脆性材料断裂性能的常用试件之一。最近的研究发现，T应力也会影响材料断裂性能，但平台巴西圆盘并没有计算T应力的解析公式。使用解析分析与有限元数值分析相结合的方法，对复合型加载条件下平台巴西圆盘试件的T应力进行了计算，并对误差进行了系统的分析。结果表明，在一定载荷分布角内相对裂纹长度 时，不管是纯I、纯II还是复合型加载条件下平台巴西圆盘计算的T应力都可以用中心裂纹巴西圆盘均布载荷下T应力计算公式来计算；T应力相对误差随着相对裂纹长度的增加而增加。

Cracked flattened Brazilian disk(CFBD) has the advantages to avoid the stress concentration of loading points, and to crack starting at the prefabricated crack tip, make it become one of the most commonly used specimens to study the fracture characteristic of brittle materials. A recent study found that T-stress can also affect the material fracture, but CFBD didn’t have an analytic formula of calculating T-stress. The finite element method combined with the analytical method is employed to systematically investigate the T-stress for the cracked flattened Brazilian disk under combined mode loading condition and systematically analyze the error and relative error．The calculation results show that within a certain range of load distribution angle, when the relative crack length is less than 0.65，the formula of the T-stress for the cracked Brazilian disk subjected to uniformly distributed pressure can be directly used to calculate the T-stress for the cracked flattened Brazilian disk under pure mode I, pure mode II and combined mode loading conditions．The relative error of T-stress increases with increasing of the relative crack length.