To see to it that the use of a large number of geotechnical construction techniques is successful, it’s a must to have efficient and safe drilling of boreholes regardless of the existing ground conditions you may be working on. Things can go for the worse if you will make use of inappropriate methods and means or the wrong kind of geothermal drilling rigs, particularly the structural conditions of ground properties by which the construction method is intending to address or rectify.
There are a handful of specialty geotechnical construction processes that necessitates hole drilling via rock or overburden. Such construction processes include anchoring, grouting, soil nailing, micro piling, and ground freezing. Typically, these holes come in 3 to 12 inches in diameter. It is also very scarce to find them come more than 200 feet deep.
These holes would also vary in their inclination. Some are vertically upwards while others would be seen as vertically downwards. Most holes would be seen in freezing, micro piling, and grouting within 30 degrees of vertical. While rock masses are naturally variable with respect to their structure, overburden, and strength – coming from the drilling point of view – this would usually present far greater difficulties and challenges to any drilling contractor.
Overburden is often seen as a non-lithified material. Nature itself forms or deposits them. There are instances also that humans create them. These materials could range from loose and soft down to something hard and dense. They can also come as something dry or saturated.
Overburdens can also contain artificial or atypical horizons or inclusions. This scenario may present a problem in terms of ground penetration. For instance, deep foundations in soils or boulders as well as shallow fill foundations and utility trenches. These conditions will be presenting the contractor with a good amount of challenge to work on, who obviously for financial reasons, are much more interested in drilling the needed holes as quickly as possible.
However, specific projects may necessitate performance requirements or significant restrictions.
Drilling systems are effective when they can deliver straight and continuous penetration in different kinds of ground soil. This ground soil being worked on could range from something extremely hard to something very soft.
It is also of utmost importance that your geothermal drilling rigs can provide you with a constant diameter from which the drilling debris can be taken. Most of the time this is consistent with what is required by the specialty construction process that it is serving. They will make use of the right amounts of rotary speed, thrust, torque, and percussive effort to reach their target in the most possible economical way.
Also, drilling rigs should be enhancing the level of efficiency of the used flushing medium. As for the ground conditions, it should determine the cost notwithstanding, even if regional experience and historical bias will have a strong impact on the choice. The technique to be used can be identified by the application.
It is also crucial that the method you will employ is aligned with the current existing project environmental restraints such as vibrations, noise, flush control, and disposal. The hole itself should be utilized only for the purpose it is intended to be used on, like the anchor tendon installation, as soon as possible right after drilling work is done. This measure will help in minimizing any time-dependent factors that induce deterioration of its walls.