Drilling Process Monitoring For Refining And Upgrading Rock Mass Quality Classification Methods

Abstract

A new technique, a new method and a new law were put forward for the refinements and upgrading of current engineering rock mass quality classification methods, i.e. the automatic drilling process monitoring(DPM) technique, the fast and direct time-series analysis of the DPM data and the DPM based findings that the curve of the drill bit advancement depth versus the net drilling time can be easily measured and calculated and that it can be represented as a set of connected linear lines. Each linear line zone has a constant slope gradient or drilling speed and represents an intact and homogeneous rock block. The position of the curve slope gradient jump between any two connected linear zones represents a discontinuity plane. DPM can offer a new measurement method and many factual data for the refinements and upgrading. Consequently, the uniaxial compressive strengths, sizes and spatial locations of rock material blocks and the associated discontinuities in underground can be rapidly, effectively, objectively and quantitatively measured and estimated. Case studies are given to illustrate, explain and describe the new technique, the new method and the new law. The approach and its associated equations were presented to refine and upgrade the current RQD,Q,RMR and BQ methods for rock mass quality classifications. The methods for objectively and effectively measure were included and the rock strength, RQD, rock mass integrity, rock hardness and discontinuities were estimated.

提出能夠完善和提升現有工程巖體質量評價方法的一套新技術、新方法和新規律。新技術為現場鉆孔過程監測(DPM)技術。新方法為鉆孔過程時空數據的快速直觀時間序列分析方法。新規律為鉆頭進深隨時間曲線呈分段線性變化,每段鉆進速度是常數,每一常數鉆速段代表一個均勻抗鉆巖石(巖塊),常數鉆速之間的突變點或低鉆速段分別為鉆孔穿過巖塊間斷面的截點或截段。DPM可以提供工程巖體質量評價完善和提升所需要的新的測量方法和數據,從而可以快速、有效、定量地測量到巖石塊體的單軸抗壓強度、大小和地下分布,以及巖石塊體之間界面斷面的產狀、延伸、凸凹起伏平整度、厚度和充填物質的物理和力學性質。通過實例來介紹、分析和解釋這套技術、方法和規律。并且給出DPM鉆孔過程監測完善和提升現有工程巖體質量評價RQD,Q,RMR和BQ方法的具體途徑和計算公式,能更客觀全面地確定巖塊單軸抗壓強度、巖體質量指標、巖體完整程度、巖石堅硬程度和間斷面。