When you need to excavate trenches or pits for any work like foundations, laying of pipes, manholes and other utilities, you need to be careful maintain the integrity of the dig site, with proper shoring. This is especially important in weak or soft soils, or in places where vibrations can cause the soil to slip.
One of the best methods for adequate shoring is the use of a slide rail trench system that enables shoring of the sides of an excavation without any vibration. In this system, slide rails are pushed into the soil and a plate that is supported by the slides in the rail is put into place. This shoring method is simple and small enough to be installed by small construction crews and does not require any elaborate equipment. The trench support system is equally easy to dismantle and all you need to do is lift out the shoring plates, pull out the rails and move it to the next spot where it is to be used, or transported back to store-yards. All these rails and plates can lay flat, making both storage and transport that much simpler.
The rails have two slides or tracks, one on the outer edge and one on the inside. To start excavation a pilot cut needs to be made of some depth into which rails at a measured distance from each other are put into place Then a panel, which measures the same as the distance between the rails is slid into the outer track or slide. The same procedure is carried out for the other side of the trench. For additional stiffness, the rails on either side may be braced against each other. The excavation can then be deepened and the rails pushed down further. As the depth of the trench increases, panels are placed on the inner edge. The slide rail trench system can be also extended in length, as rails have slides on all four sides, that enables shoring to be taken in any direction. Once the desired depth is reached, the installation of the desired service can be completed.
After this work of installation is completed, backfilling can be commenced, and inner panels can be extracted. The rails need to be pulled up along with the outer panels once the backfilling and its desired degree of compaction is completed. The shoring material needs to be adequately cleaned and taken to the next site for reuse.
The traditional method of installing underground facilities like water lines, sewer lines, electrical cables and other utilities is to dig open trenches to the required levels, and then backfilling them after the work is completed. This process causes a complete disruption of the area and can lead to many problems for traffic, safety, and other aspects.
A trenchless method for construction of underground facilities, also known as micro tunneling helps to greatly reduce the inconvenience caused by open and deep trenches. A guided boring system uses a remote control to operate the boring machines. A guidance system is used to correctly position the utility in its required alignment, while the pipes are placed in position by jacking them into place. It is required to balance groundwater and earth pressures by exerting continuous pressure at the face of the excavation made for the machines.
In a guided boring system, the machinery is installed in a pit that is on the alignment of the required utility and at the correct depth. Guidance can be enabled by lasers or other techniques that ensure that the boring is carried out in the required alignment and depth. A pilot tube displaces soil as it is moved forward by augers that pull the tube into place. This method is suitable for soils that can be easily displaced. It is possible to install pipes up to a distance of 120 meters with this method. Inspection chambers or manholes are positioned at these distances and the same can also be used to extend the pipelines in the required direction. These spots can suitably be used for changing of direction or alignment.
Guided systems are useful for installing smaller diameter pipes where precision is important for the right grade, as in the case of sewer lines that operate by gravity. Pilot tubes are installed behind pilot heads and the drilling is continued to the exit point. A reaming head that has the required diameter, is then installed behind the pilot tubes. As the auger with the required pipes moves forward, a required section of the pilot tube is removed. The augers need to be of the same size as the outside diameter of the pipes that need to be installed. Pilot tubes help to install the final pipe in the correct alignment. These systems allow for very exacting tolerances which are demanded during the laying of sewers.