Slipform construction is a method of building concrete structures in which hydraulic jacks continuously lift a form while the concrete is poured. The result is a continuous vertical surface. Contractor Ryan Edward Rock of Ankeny, Iowa, points out five advantages of slip-form construction.
Faster completion of projects
Slipform construction is faster than traditional construction methods because it allows for continuous concrete pouring. As the contractor pours quick-setting concrete, the form is raised vertically. The concrete is set before the form is raised.
Higher quality of finished product
Slipform construction can produce a higher-quality finished product because continuous concrete pouring allows for a smoother and more consistent surface. But quality depends on the contractor’s know-how, Ryan Rock says. Concrete can flow down and mar the surface if the form is moved too quickly. If the contractor doesn’t move the form fast enough, the amount of force required to keep the form moving can overwhelm the equipment.
Greater worker safety
Slipform construction greatly reduces the need for workers at high elevations. There are fewer workers at risk at every stage of the operation. Also, the form is never released from the structure as it is elevated. It’s joined at multiple points, so workers are less likely to be injured in disassembly than other concrete pouring methods.
Slipform construction costs less
Slipform construction saves on both labor and materials. In recent years, slipform contractors have mastered stringless methods. Eliminating stringline allows projects to be completed with a smaller crew and more room for moving equipment around.
Slipform construction methods are versatile
If it’s made from concrete, it can be made with a slipform. Slipform molds have made pylons, towers, bridges, and silos.
Ryan Rock anticipates some common questions about slipform
Contractor Ryan Rock says that certain customer concerns come up frequently in slipform construction projects.
- Lead time. Getting equipment and molds to construction sites can sometimes be done in as little as 10 days, but sometimes it can take as long as 10 weeks. It’s better to start planning early since small design changes require major equipment changes.
- Getting equipment and mold to the site is usually the general contractor’s responsibility. Your contract may vary, however.
- Your contractor will need a crane to assemble the forms and to put them in place. Cranes are also necessary during sliding for supplying concrete and rebar. Your contractor will also need a crane to dismantle the mold.
- Power on site. Every slipform construction site requires a power hookup or a generator. Power is necessary to run pumps, lighting, and small tools.
- Water on site. Water is a necessity for finishing the concrete and cleaning the forms. Workers need water to stay hydrated. Usually, a refillable 300-gallon tank of water is enough.
- Concrete can be poured even on rainy days. It does not mix with rainwater.
The secret to success in slipform construction, Ryan Edward Rock says, is working with an experienced, knowledgeable contractor. Contact Empire AG in Ankeny, Iowa, for the answers to all of your questions.