Economical Design & Drawing of Spill through Abutment with Post Tension Superstructure

The Spill-through abutments usually support the bridge periodically through its span. While they do not include wing walls or a back wall to retain the embankment, the deck rests on a beam supported by columns or a short wall. Water or roadways are able to pass between the supports. The length of the support structure varies to accommodate the distance between the level bridges. When the embankment height is large and the existing canal or waterway is not disturbed the spill through abutment is considered more economically than wall type abutment. The idea is that each footing takes the concentrated load of the column and spreads it out over a large area, so that the actual weight on the soil does not exceed the safe bearing capacity of the soil. Post-tensioning is a method of reinforcing (strengthening) concrete or other materials with high-strength steel strands or bars, typically referred to as tendons. Post-tensioning applications include office and apartment buildings, parking structures, slabs-on-ground, bridges, sports stadiums, rock and soil anchors, and water-tanks. In many cases, posttensioning allows construction that would otherwise be impossible due to either site constraints or architectural requirements. . Post-tensioning tendons, on the other hand, are considered “active� reinforcing. Because it is prestressed, the steel is effective as reinforcement even though the concrete may not be cracked. Post-tensioned structures can be designed to have minimal deflection and cracking, even under full load.