Small Scale Equipment
Simultaneously jack pipe through the earth while removing the spoil inside the encasement by means of a rotating auger. Auger boring consists of a dry rotating auger driven through a jacked steel casing. Typically placed in a pit on grade with the bore profile and exits into an exit pit. Using a two casing system, some steerage is possible. Widely used for road crossings up to 60" in diameter .
Wet Boring/Guided Boring using a hollow bore rod and a pressurized jet of water or drilling fluid. A cutting head and dry percussive drill head can also be used. Bore head can be angled and steered by rotating the bore rod. These holes can be enlarged with a reamer. For smaller diameter, shorter installations.
Fun and Informative stories about pipe ramming.
Pipe Ramming - Involves the use a pneumatic hammer to drive a steel casing through the ground. Soil is excavated from the casing with compressed air, an auger or jetting. With small diameters it is possible to ram closed-end pipes. This method is frequently used to cross roads, railways and other embankments.
Small Scale Tunnels built with the Drilling and blasting method. The smallest practical cross section of a tunnel is around 4 m. This area gives space for ventilation tubing and small excavation equipment. Tunnel areas of 4 to 6 m. The cut-and-cover method of tunneling begins with excavating a trench, constructing a tunnel within the trench, and then covering it. This restores pedestrian and vehicular traffic quickly and avoids long-term disruptions. This method accommodates changes in tunnel width and non-uniform shapes, which are necessary to build ramps and interchanges.
This paper reports applications of engineering techniques of cut-and-cover tunneling and underground stations carried out Adana Light Rail Transit System (Adana Metro). The tunnel was executed using the cut-and-cover construction method.
Sequential Excavation Method (SEM) also is known as New Austrian Tunneling Method (NATM)
because it was developed in Austria, but it is now commonly used throughout the world. It entails dividing the space to be excavated into segments, then mining the segments sequentially, one portion at a time, using supports. Each tunnel is supported individually before the next tunnel is excavated. SEM allows a tunnel of any shape to be excavated.
