高级检索

随钻信号对岩石单轴抗压强度响应特征及反演模型

Modeling study of uniaxial compressive strength prediction from similar analog drilling test signals

  • 摘要: 岩石单轴抗压强度是岩土工程与地下工程中表征岩体性质的重要参数之一。为了准确、快速地感知、预测煤矿井下岩体的岩石单轴抗压强度,以室内9种不同配比的相似材料试件钻取试验为基础,构建基于随钻振动信号的单轴抗压强度GA−BP(Genetic Algorithm−Backpropagation)神经网络预测模型。通过改变GA−BP神经网络的隐含层数、种群数和训练函数,讨论分析预测模型影响因素与结果,确定最优预测模型结构。结果表明:随钻振动信号与相似模拟材料的单轴抗压强度之间具有响应关系,所构建预测模型准确率都在70%以上,以随钻振动信号感知预测单轴抗压强度的研究方法具有一定的可行性;训练函数选择trainlm、隐含层为8、种群数为20时模型结果最优,训练集、测试集决定系数分别为0.761、0.745,均方根误差分别为6.039、4.254 MPa,平均绝对误差分别为6.574、4.716 MPa。提出的单轴抗压强度预测方法可为岩石力学性质的智能辨识提供新的思路。

     

    Abstract: Uniaxial compressive strength (UCS) of rock is one of the important parameters to characterize the properties of rock mass in geotechnical and underground engineering. In addition, in order to perceive and predict the UCS of rock in underground coal mines accurately and quickly, a GA−BP (Genetic Algorithm-Backpropagation) neural network prediction model of UCS based on vibration signals from drilling is constructed based on drilling tests of nine specimens of similar materials with different ratios in the chamber. By varying the number of hidden layers, population and training function of GA−BP neural network, the factors affecting the prediction model and the results are discussed and analyzed to determine the optimal prediction model structure. The results indicate that there is a responding relationship between the vibration signal with drilling and the UCS of similar simulated materials, and the accuracy of the constructed prediction models are above 70%, and the research method of predicting the UCS with the perception of vibration signal with drilling has certain feasibility; The model results are optimal when trainlm is chosen for the training function, the hidden layer is 8, and the number of populations is 20,with coefficients of determination of 0.761 and 0.745 for the training set and the test set, respectively, the root-mean-square errors are 6.039 MPa and 4.254 MPa, and the mean absolute errors are 6.574 MPa and 4.716 MPa, respectively. The UCS prediction method proposed in this paper may provide a new idea for the intelligent identification of rock mechanical properties.

     

/

返回文章
返回