Pre-Load Reservoirs
DESIGN PRINCIPAL
Preload tanks are cylindrical pre-stressed concrete shells whose, base or top or both is partially or wholly restrained against translation or angular rotation. This restraint at base and at top introduces edge forces and moments which induce local bending in the wall. The process of pre-stressing both vertically and horizontally, is then designed such that when the tank is full, the ring forces created, do not cause any circumferential tensile stresses in the concrete.
A large proportion of these tanks, were covered with a concrete domed roof. Hence additional pre-stressing would have to be incorporated to resist the thrust from this structure.