目前对TBM滚刀破岩效率评价大多采用量化计算破岩比能（ηse ）的方法，其中岩石破碎体积为影响破岩比能的关键因素，岩石在滚刀作用下的破坏体积与其破坏方式关系密切。为此，结合岩石不同破坏方式，讨论了岩石破碎体积的一种简易实用的计算方法。基于岩石破坏过程中以剪切破坏和张拉破坏为主的特性，提出了以岩石破坏时裂纹长度与剪切面在岩石自由表面投影长度以及滚刀刀刃宽度之间的关系来识别岩石破坏方式，在此基础上计算岩石破碎体积，结合CSM预测模型，推导出一种破岩比能水平量化计算方法。通过实例对该方法进行计算验证，分析了破岩比能（ηse ）与刀间距（S）、刀具磨损量（w ）之间的关系，得出了ηse －S曲线与ηse － w曲线，表明存在最优刀间距，且随着磨损量增大，比能值也将增大。所述的预测模型能够对TBM破岩时刀间距的优化、刀具的更换提供理论依据。%To evaluate the efficiency of TBM disc cutters ,the common practice is to calculate the specific energy for rock breaking with the volume of fragmentized rocks as the key influencing indicator .Different fragmentation methods result in varied volumes of fragmentized rocks when adopting TBM disc cutters . Based on the study of different fragmentation mechanism ,such as shear failure ,tensile failure ,compression failure and the combination of multiple failure modes ,a simple method to calculate the volume of fragmentized rocks was put forwarded .Based on the fact that the shear failure and tensile failure are the main forces during the fragmentation ,an identification method of different failure modes was suggested based on the quantitative relationship of the crack length ,the projected length of the shear failure surface and the width of the cutter .And then the volume of fragmentized rocks was calculated to derive a new algorithm that could quantify the specific energy with the help of a CSM model .Finally ,an example was used to prove the feasibility of this method .The relationship between specific energy and the cutter space ,also the relationship between specific energy and the wear condition was analyzed ,from which the ηse - S curve and the ηse -w curve were obtained .This application proves that there is an optimal cutter space ,and the ηse increases with the wear condition .This model could be used to provide a reference for the performance prediction and optimization of TBM disc cutters .
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