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The principle behind the prestressed concrete tank is that the compressive stresses induced by the high-strength steel tendons inside a concrete member prior to the loads being applied will balance tensile stresses inflicted in the member during the service. It`s recognized that prestressing eliminates several design limitations and conventional concrete places on load and span and allows the building of roofs, bridges floors, and walls with elongated unsupported spans. With this in mind, architects and engineers design as well as build lighter concrete tanks without sacrificing strength.
This principle behind prestressing in concrete tank can be illustrated in a row of books being moved from one place to another. Instead of vertically stacking the books and carrying them, they may perhaps be shifted in horizontal position by putting pressure to the books right at the end of row. Whenever sufficient pressure is applied, the compressive stresses are induced all over the entire row, and so the whole row can always be carried and lifted horizontally at once. This principle has been applied to the design and construction of concrete tank.
Concrete water tanks are broadly used in today’s society as a results of the endless need to have potable water easily accessible. Concrete water tanks are used for several purposes such as the storage of potable water, rain water harvesting and even for agriculture irrigation. They are comparatively easy to construct and they have numerous advantages compared to other tanks of different materials such as plastic or steel. Concrete tanks have bigger life spans, they can always be built bigger compared to their counterparts, they don’t taint water and besides, they can always be buried underground.
Having a concrete tanks buried underground performs an aesthetic purpose and a practical one since it keeps the water cool. Consequently, the tank will have much less algae growth. A lesser algae growth implies fewer pump problems. Normally potable water tanks are built with prestressed concrete for purposes of durability and water tightness. Literature review As with all sorts of liquid-retaining constructions the fundamental problem of the design is not simply one of securely supporting the load, but is of creating a form that stays liquid-tight under service conditions.
Consequently, leakage where it occurs happens more regularly from defects in detail and/or workmanship than from direct result of an inadequate design. In the prestressed cylindrical concrete tank, the enclosed liquid stimulates ring tension in horizontal section and also generally some bending in vertical section. Vertical and Horizontal stressing are applied as obligatory to offset these effects. In a form of this kind, they have the advantage that the central concrete shell is exposed to minimum situations of stress under complete load from the enclosed liquid.
The base of the calculations for structures of this sort is simple. However, the application results, in practice, to possible disparity in interpretation. The provided degree of restraint at the wall foot possesses a controlling effect on the allocation of stress in the tank wall. The
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