黄河封冻期河冰的劈裂性能试验研究

Research on Splitting Performance of River Ice of Yellow River in the Freezing Period

为研究黄河河道内天然河冰材料的力学性能,采用巴西圆盘劈拉试验方法,对黄河天然冰的劈拉强度和断裂韧度进行试验研究。试验过程中,冰样的控制温度分别为-3、-5、-7、-10、-15℃,冰样直径分别为60、70、80、100 mm。试验结果表明:温度在-15^-3℃范围内,黄河冰的劈拉强度随着温度的降低逐渐增大,断裂韧度随着温度的降低先减小,而后逐渐增大。此外,当冰样直径在60~100 mm范围内时,黄河冰的劈拉强度具有一定的尺寸效应,随着试样尺寸的增大,黄河冰的劈拉强度逐渐减小,而断裂韧度没有明显的变化。

With the method of Brazil disk split strength test,the tensile strength and fracture toughness of the Yellow River ice were researched.During the experiment,the control temperatures of ice sample were-3,-5,-7,-1 0 and-150C respectively.Specimen sizes of ice sample were 6 0,7 0,80 and 100 mm respectively.Test results show-that the tensile strength increases as the temperature decreases when temperature is in-1 5-3℃range,fracture toughness decreases in lower temperature at the start and then gradually increases.In addition,the tensile strength of river ice has a certain size effect when specimen size is in 60-100 mm range.In a certain range,with the increase of specimen size,the tensile strength decreases and the fracture toughness has no obvious change.The research results provide a useful test method for analyzing the fracture performance of river ice and provide effective mechanics parameters of river ice for discussing river ice crack in the Yellow River.