precrack meaning in English

预制裂纹

Analysis of effect of precrack in roller compacted concrete gravity dam
整体式碾压混凝土重力坝预裂缝的效应与分析
In this paper , the high - temperature low - cycle fatigue life and fatigue crack propagation life tests are carried on the cylindrical axial symmetry specimens having precrack or non - precrack with different types of notches of 16mnr steel in common use in the petrochemical industry contacting coke drum equipment , the stress / strain and the range of stress / strain of dangerous points are received through stress analysis of the specimens using finite element program under multi - axial stress state . at last , the equations of evaluating the high - temperature low - cycle fatigue life and the fatigue crack propagation life are found through using the least - square regression method
本文采用无预裂纹和带预裂纹环状缺口圆柱形试样，进行了石化焦炭塔设备常用材料16mnr多维应力状态下不同缺口形式的高温低周疲劳总寿命试验及裂纹扩展寿命试验，并利用有限元程序对试样缺口周围及裂纹尖端附近进行了轴对称多维应力状态下的应力、应变场分析，来评价材料不同条件下的高温低周疲劳总寿命和裂纹扩展寿命，最后利用最小二乘回归方法，得到了该材料高温低周疲劳总寿命和裂纹扩展寿命评价方程。