为解决单体式锚杆钻机施作小孔径锚索深锚孔时钻进工效低的问题，以木寨岭公路隧道车行通道为工程依托，在分析设计空间边界与主要岩性特征的基础上，研制以切削钻进为主、冲击破岩为辅，适用于隧道小空间断面施工的小孔径锚索钻车，计算小孔径锚索钻车设计过程中切削、冲击等关键技术参数，并对钻杆强度进行校验；然后，在现场开展多型钻孔设备的钻孔对比试验。结果显示： 1）研制的小孔径锚索钻车外形尺寸为2 950 mm×1 230 mm×2 650 mm (长×宽×高)，满足小空间断面的施工需求； 采用在旋转式钻机上设置冲击器的方式，可以实现“旋转-冲击”钻进; 在高速旋转切削钻进的基础上搭配低周期性的低冲击能，可以实现在以软岩为主、兼顾软硬互层围岩中的有效钻进。2）在软岩地层，“小孔径锚索钻车+B25钻杆+32 mm钻具”相比旋转式钻机、冲击-旋转式钻机更适合施作小孔径锚索深锚孔，最大可钻进深度超15 m，钻进5 m耗时约16 min，钻进10 m耗时约36 min。
To address the challenge of low drilling efficiency when using a single-unit anchor drilling rig for long anchor holes in small-aperture prestressed anchor cables, a case study is conducted on a vehicle passage of the Muzhailing highway tunnel. The spatial boundary conditions and primary lithological characteristics of the surrounding rocks are analyzed, and an anchor cable drilling vehicle is developed using cutting drilling as the primary method, with impact rock breaking as an auxiliary method. This drilling vehicle is suitable for small space sections in soft-rock tunnel construction. Key technical parameters, including cutting and impact forces, are determined during the design phase, and the strength of the drill rod is verified. Subsequently, comparative on-site drilling tests are performed using multiple types of equipment. The main conclusions are as follows: (1) The developed small-section anchor cable drilling vehicle has overall dimensions of 2 950 mm (length) × 1 230 mm (width) × 2 650 mm (height), meeting construction requirements for small-section spaces. It employs a rotary drilling vehicle equipped with an impactor to achieve combined "rotary-impact" drilling. By combining high-speed rotary cutting drilling with low-frequency, low-impact energy, the system enables effective drilling primarily in soft rock while accommodating soft-hard interbedded surrounding strata. (2) Compared to conventional rotary drilling rigs and impact-rotary drilling rigs, the combination of the small-section anchor cable drilling vehicle, a B25 drill rod, and a 32 drilling tool is more suitable for efficiently constructing deep anchor holes for smallsection prestressed anchor cables in soft-rock strata. The maximum drilling depth exceeds 15 m, with drilling times of approximately 16 and 36 min for 5 and 10 m, respectively.
