Cable-stayed bridge are as follows: There are four major classes of rigging on cable-stayed bridges: "mono", "harp", "fan," and "star". There are also four arrangements for support columns: "single", "double", "portal" and "A-shaped". Depending on the design, the columns may be vertical or angled or curved relative to the bridge deck. A side-spar cable-stayed bridge uses a central tower supported only on one side. This design allows the construction of a curved bridge. Far more radical in its structure, the Puente del Alamillo (1992) uses a single cantilever spar on one side of the span, with cables on one side only to
Pontoon (boat) boat without much warning, particularly a top-heavy boat. Common boat designs are a catamaran with two hulls, or a trimaran with three hulls. Boats with three hulls are sometimes called "tri-toons." Small inflatable pontoon boats are one or two person, catamaran type boats, designed for leisure and fishing. Their pontoons are made out of abrasion resistant PVC and nylon with aluminum, steel and/or plastic frames for support. In today’s setting, more and more people prefer to use frameless pontoon boats. They are powered with paddles, oars and often with electric trolling motors using deep cycle lead batteries. Commonly they are