Over the past decades,a proven anchor-drilling technique has often been used to secure rocky slopes or underground passages.However,in certain mountainous geotechnical situations,long anchors with either cable bolts o...Over the past decades,a proven anchor-drilling technique has often been used to secure rocky slopes or underground passages.However,in certain mountainous geotechnical situations,long anchors with either cable bolts or steel rods need to be installed using directionally controlled methods.One ideal method is the horizontal directional drilling technique(HDD technique),which allows exact monitoring of the bore,thereby precisely following a calculated curvature path over long anchor lengths.In this paper,the authors introduce a new directional drilling method that allows the installation of such long anchors under the given situations.展开更多
文摘Over the past decades,a proven anchor-drilling technique has often been used to secure rocky slopes or underground passages.However,in certain mountainous geotechnical situations,long anchors with either cable bolts or steel rods need to be installed using directionally controlled methods.One ideal method is the horizontal directional drilling technique(HDD technique),which allows exact monitoring of the bore,thereby precisely following a calculated curvature path over long anchor lengths.In this paper,the authors introduce a new directional drilling method that allows the installation of such long anchors under the given situations.
