基于数字图像相关方法的黄河冰断裂性能研究

河冰的断裂性能是衡量河冰承载力、模拟和预测开河的重要参数。为明晰黄河冰的断裂性能,基于数字图像测量技术(Digital Image Correlation,DIC)开展了黄河冰的三点弯曲梁试验,分析了不同条件下试样的断裂形态,研究了温度和加载速率对黄河冰断裂韧度的影响。研究结果表明:DIC方法适用于黄河冰断裂试验的研究;黄河冰试样的断裂形态主要受到晶体形态的影响,试样的破坏形式以Ⅰ型断裂为主;黄河冰断裂韧度随着加载速率的增加而降低,随着温度的升高而减小,但在试验给定温度范围内降幅较小;提出了黄河冰断裂韧度与温度、加载速率的关系式,为极限荷载作用下河冰断裂过程的分析及冰荷载断裂参数的选用提供了依据。

Research on ice fracture of the Yellow River performance based on digital image correlation method

The fracture performance of river ice is an important parameter to measure the bearing capacity of river ice and to simulate and predict the data of ice breakup. In order to clarify the fracture performance of the Yellow River ice, a three-point bending beam test of the Yellow River ice was carried out in combination with Digital Image Correlation. The fracture morphologies of the ice sample were analyzed in different conditions,and the influence of temperature and loading rate on the fracture toughness of the Yellow River ice were studied. The results show that the DIC method is suitable for the fracture tests of river ice. The fracture morphologies of ice are mainly affected by the crystal structure, the failure mode of the ice sample is mainly type I fracture. The fracture toughness of the Yellow River ice decreases with the increase of the loading rate and temperature, but within the given temperature range, the range of decrease is small. A relationship formula of Yellow River ice between the fracture toughness, temperature and loading rate is proposed, which provides a basis for analyzing the fracture process of river ice under ultimate load and selecting the fracture parameters of ice load.