You will prepare and submit a term paper on Techniques for Roadway Tunnelling. Your paper should be a minimum of 1250 words in length. Due to increased population and massive migration to urban areas, infrastructural facilities have either to be constructed high above the ground or deep into the substrata where conditions are uncertain. This essay seeks to dissect a review of a number of techniques for roadway tunneling in various conditions and the attributed advantages and disadvantages shall be discussed.
Tunnels, both artificial and natural, exist in various shapes and can be constructed by various techniques. Tunnels are sorted as underground and underwater passageways, transporting and carrying passengers, freights, water, and sewage through pipes. For example, Gerrards Cross Tunnel in England and The Natural Tunnel State Park in Virginia, USA are being used as a train tunnel and railroad tunnel respectively.
Tunneling has been in existence for a long time as evidenced since the 1700s as evidenced by the historic Fritchley Tunnel, in Crich, Derbyshire, which can be traced back to 1793(Daily mail UK., 2013).
Tunnels are structures that require special design considerations that may include lighting, ventilation, fire protection systems, and emergency egress capacity based on the owner’s determination” (Thompson et al., 2011).
Conventional tunneling can be referred to as the construction of underground openings of any shape with a cyclic construction process composed of excavation, by using the drill and blast methods (explosives) or very basic mechanical excavators, mucking as demonstrated in Figure 1 and
Placement of the primary support elements such as steel ribs or lattice girders, soil or rock bolts, and sprayed or cast in situ concrete.
In certain instances grouting is used to reinforce the soil or face of the tunnel to avoid collapse or failure. The most commonly used grouting material is cement.
Today, tunnels are an increasingly necessary part of our road and rail networks and continue to be employed to support our water, sewer, and utility systems.