Different Techniques Used for Well Foundation Construction Focused on Pneumatic Cassion Technique: A Review

Well foundation is a kind of deep foundation that is conventionally allocated beneath the water plane for bridges. Different techniques that are used for the construction of well foundation and well sinking are horizontal drilling by divers, grabbing method, jet air method, jet water method, jack-down technique, vertical cutting edge method, pneumatic caisson technique, etc. The objective of the present study is to review different types of well foundation construction techniques with a case study of pneumatic caisson technique. Pneumatic caisson techniques are mainly used in hilly and rocky areas. Pneumatic caisson is a kind of caisson which is shut at the top and revealed at the bottom when in construction. The water is ceased from the caisson cell or chamber by dint of consolidated air. Pneumatic caisson mainly holds control over the work and preparation of the foundation in the rocky area for the sinking of caisson. Only with an absolute attentive observation, the caisson can be imperiled in a supine position. The bottom of the cell should be closed adequately with concrete as it may have chances to be placed on dry bottom. The excavation takes place, under the very high pressure and worker can go inside for inspection of work, and some kind of health hazard may occur for this method. There are many advantages as well as disadvantages for all the above techniques used for well foundation.