The downward force include the total weight of the soil (= submerged soil weight + weight of water) on top of the concrete mass for the case that the foot-print of the tank is smaller than the concrete base.
In the practical design of dams and submerged structures, it is usually first to compute the hydrostatic pressure, measured from the free water surface to any surfaces exposed to the uplift due to water (p = 62.4*h). Then compute the uplift force (U = Sum:p*A). The last is to compute the...
Field welding is quite difficult not to mention full pent around W-Shape under a tight space. The welding inspector may have do you and the welder both a big favor to provide a practical solution and to ensure a sound weld joint at a difficult situation (the beams may be distorted due to the...
1. Visual inspection can tell the tears & wears (section loss), and NDT can identify cracks. Any doubt in mind, replace the clamps and tighten to the specified level.
2. If clamps are in good shape, and no indication of cable slipage, I don't think there is a need for re-tightening.
This is only a personal opinion, if a shallow section can carry the loads above the opening without shear concerns, then the entire (deeper) section needs not to be classified
as a beam (flexural) element, it can be reinforced as walls with additional reinforcing around the opening and the corners.
Uplift and over-stressed soil which causing uneven settlement usually are not problems of this type foundation - monolithic slab with thickened areas for columns, since if properly reinforced, the slab acts, just as the name indicated, monolithically to resists the forces delivered by the...
The hair-pin design is valid only when the column is supported directly on top of the pedestal of the footing, which in turn is seperated from the slab-on-grade through expansion joint. When the lateral load from the column causes the pedestal deflect outward, thus introduces tension in the...
The seismic force has negligible effect on the concrete block foundation itself, however, the increased pressure on the soil below and the overall structural stability need to be investigated.