VSL’s DuraStor™ Tanks are cast-in-place, prestressed concrete liquid storage tanks primarily reinforced with post-tensioning tendons. High-strength steel tendons apply compression to the tank floor, walls and roof to counteract the applied forces and provide residual compression. This method actively reinforces the structure and significantly enhances its watertightness and long-term durability.
The design and construction of DuraStor™ Tanks are governed by national building codes ACI 350 and AWWA D115. Additionally, the Post-Tensioning Institute (PTI) provides numerous specifications and guides on the design, fabrication, handling, storage, placement and inspection of post-tensioning systems. Post-tensioning is a proven technology with decades of successful applications on thousands of structures worldwide including bridges, high-rise buildings, foundation systems, parking structures, silos for granular material storage and liquid storage tanks.
Versatile
VSL’s DuraStor™ Tanks can be constructed in many shapes to suit project needs. Shapes include circular, rectangular, rectangular with rounded corners, egg-shaped digesters, irregular-shaped polygons and oval – there are no practical limitations with this method of construction. Tanks have been constructed with capacities ranging from 250,000 gallons to above 30,000,000 gallons.
DuraStor™ Tanks are appropriate for all types of liquid containment including chilled and potable water, storm water retention, sludge, wastewater, digesters, ethanol, petroleum products and liquefied natural gas. They also are used in the storage of granular materials such as coal, grains, ash, cement, clinker and nuclear containment.
Site conditions may require that the tank be constructed fully-buried, partially-backfilled, above-grade, in sloped backfill or in conditions where ground water is above the tank floor. VSL’s DuraStor™ Tank is adaptable to any of these conditions. Additionally, walls can have any architectural finish to meet project requirements.
Durable
Because of its durability, cast-in-place post-tensioned concrete is recognized as the preferred method of construction for many types of structures exposed to the environment and other corrosive elements. Post-tensioning tendons have multiple layers of corrosion protection including the highly pre-compressed concrete cover, thick polyethylene ducts filled with high-performance grout or a corrosion-inhibiting coating, encapsulated anchorages and watertight duct connections. With the highly developed design methodology, structural detailing and applications in high seismic zones - prestressed concrete tanks have the proven ability to withstand severe earthquakes.
Constructable
VSL DuraStor™ Tanks require no proprietary construction methods or construction equipment - eliminating the potential for project delays due to unavailable proprietary equipment or materials. The post-tensioning allows for thinner members resulting in reduced materials, placement labor, construction schedules and costs compared with other types of concrete tanks. Additionally, the construction sequencing of a post-tensioned concrete tank allows for multiple tasks to be accomplished simultaneously - resulting in a highly efficient use of manpower and short construction duration. Work can progress under freezing conditions with proper protection and curing of concrete members.