Cichański Artur, Topoliński Tomasz, Nowicki Krzysztof
Faculty of Mechanical Engineering, Bydgoszcz University of Science and Technology, Kaliskiego 7, 85-796 Bydgoszcz, Poland.
Materials (Basel). 2025 Jan 8;18(2):232. doi: 10.3390/ma18020232.
This paper presents an experimental method for estimating the fatigue limit of trabecular bone using a single trabecular bone sample, the microstructural parameters of which were determined by microCT. Fatigue tests were carried out using the Locati method, with stepwise increasing load amplitude. The fatigue limits of the trabecular structures were determined experimentally in accordance with Miner's law of fatigue damage accumulation, based on the parameters of the reference S-N curve taken from the literature. On the basis of the fatigue limits, the S-N curves were determined for the tested samples, and from them the compressive strength corresponding to the fatigue limit for the = 1 cycle. Ultimate compressive strength was determined as a result of compression to failure tests. Computational dependencies combining the index with and the index with were formulated. To verify the proposed method, two groups of human trabecular bone samples were analysed: = 42 were tested under monotonic loading, and = 61 were tested under cyclic loading with stepwise increasing amplitude. The statistical test of the distribution conformity of the calculated compressive strength to the experimental ultimate strength was performed. The results of the Kolmogorov-Smirnov statistical test were = 0.19 ( = 0.314). The agreement of the distributions of , as determined experimentally and calculated from the computational dependencies, was also tested statistically, with the result of the Kolmogorov-Smirnov test being = 0.286 ( = 0.065). A similar analysis performed for yielded = 0.238 ( = 0.185).
本文提出了一种使用单个松质骨样本估计松质骨疲劳极限的实验方法，该样本的微观结构参数由显微CT确定。采用洛卡蒂方法进行疲劳试验，载荷幅值逐步增加。根据从文献中获取的参考S-N曲线参数，依据Miner疲劳损伤累积定律，通过实验确定了松质结构的疲劳极限。基于疲劳极限，确定了测试样本的S-N曲线，并从中得出对应于10^6次循环疲劳极限的抗压强度。通过压缩至破坏试验确定了极限抗压强度。建立了结合σf指数与σu以及εf指数与εu的计算关系式。为验证所提出的方法，分析了两组人松质骨样本：42个样本进行单调加载测试，61个样本进行幅值逐步增加的循环加载测试。对计算得到的抗压强度与实验得到的极限强度进行了分布一致性的统计检验。柯尔莫哥洛夫-斯米尔诺夫统计检验结果为D = 0.19（p = 0.314）。还对实验测定的和根据计算关系式计算得到的σf分布一致性进行了统计检验，柯尔莫哥洛夫-斯米尔诺夫检验结果为D = 0.286（p = 0.06）。对εf进行的类似分析得到D = 0.238（p = 0.185）。
