摘要
旋推功率比(RTPR)可以从钻进破岩机理角度描述破碎不同岩土层所需切应力与正应力的差异,通过与钻进比能(SED)指标的预报效果进行对比研究发现:钻进参数的同步变化对RTPR指标定位软硬界面位置无显著影响,相比可知钻进比能可以得到更精确的预报效果。因此,应用RTPR指标对广西某大型岩溶隧道进行充填溶腔与硬质灰岩区域界面识别,并一步根据曲线特征判断传统预报中缺失钻孔排渣与返液的预报不确定区,最后通过掌子面已知条件预测未知地层的岩性。此方法在实际钻探预报中准确预测了前方地层的岩性,可以为隧道地质的精细化预报提供有效的参考。
RTPR can describe the difference between shear stress and normal stress required to crush different rock and soil layers.Compared with the prediction effect of SED index,it is found that the synchronous change of drilling parameters has no significant impact on the location of the soft and hard interface of RTPR index,and a more accurate prediction effect can be obtained.Based on this theory,the regional interface between filling cavity and hard limestone is identified for a major tunnel project in karst area of Guangxi,and the uncertain prediction area due to lack of drilling slag and return fluid in traditional prediction are judged according to the curve characteristics.Finally,the lithology of unknown stratum is predicted by known conditions of the face.This method has accurately predicted the lithology of the unknown strata in the actual drilling prediction,which can provide effective reference for the refinement of geological prediction of tunnels.
作者
刘宗辉
关启钰
饶坤荣
林显荣
李战春
LIU Zong-hui;GUAN Qi-yu;RAO Kun-rong;LIN Xian-rong;LI Zhan-chun(College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Guangxi Road Construction Engineering Group Co.Ltd.,Nanning 530001,China;Guangxi Xinfazhan Communications Group Co.Ltd.,Nanning 530028,China)
出处
《公路》
北大核心
2021年第11期342-349,共8页
Highway
基金
国家自然科学基金项目,项目编号51708136
广西科技计划项目,项目编号桂科AD19245153
中国博士后基金,项目编号2019M653310。
关键词
隧道地质预报
超前钻探
钻进比能
旋推功率比
geological prediction of tunnel
advanced drilling
drilling specific energy
rotation-to-thrust power ratio
