基于损伤力学的碟盘刀具振动截割煤岩径向载荷

Radial load of vibration cutting coal and rock with disc cutter based on damage mechanics

为探究碟盘刀具振动截割煤岩的载荷特性与破碎性能,根据煤岩损伤力学和Mohr-Coulomb强度准则,构建碟盘刀具径向载荷损伤力学模型,利用ABAQUS软件和振动截割实验台获得碟盘刀具振动截割煤岩径向载荷谱,采用峰值标准差和频谱分析实验载荷谱,表征截割过程中煤岩崩落的状态,验证了径向载荷理论计算值、数值模拟值和实验值的一致性。结果表明:截割煤岩厚度为10~25 mm时,数值模拟和实验的径向载荷峰值均值与理论值平均误差分别为3.17%和7.66%,与理论值吻合度较高,验证了力学模型的准确性;截割煤岩厚度增加,径向载荷呈线性增大趋势,载荷谱峰值标准差呈指数规律变化,载荷谱波动频率中幅值的低频成分相对占比随之增大,煤岩大块崩落的概率增大。

This paper intends to explore loading characteristics and fracturing properties of disc cutter vibration cutting coal rock.The study involves developing a mechanical model of disc cutter radial load damage based on coal rock damage mechanics and Mohr-Coulomb strength criterion,using ABAQUS software and vibration cutting test bench to obtain radial load spectrum of coal and rock cutting in pace with disc cutter vibration,characterizing the collapse state of coal and rock during cutting by analyzing and testing load spectrum with peak standard deviation and spectrum,and verifing the accuracy of the model by comparing the theoretical calculation value,numerical simulation value and experimental value of radial load.The results show that radial load peak value is in good agreement with the theoretical value with the mean error 3.17%and 7.66%,as the thickness of cut coal and rock ranging between 10-25 mm,which verifies the accuracy of the mechanical model.The radial load increases linearly depending on the increase of thickness of cut coal and rock,the standard deviation of peak value of load spectrum changes regularly,along with increase of the relative proportion of low frequency component of amplitude in fluctuation frequency of load spectrum,and the increase of large coal and rocks collapsing probability.