Reinforced concrete is one of the most versatile, practical, and durable construction materials used today, and it is a particularly popular material in the parking garage construction industry. However, traditional reinforced concrete, which is strengthened with black steel rebar, has a number of shortcomings.
For modern reinforced concrete structures, including multi-level parking garages, rebar made from glass fiber reinforced polymer (commonly referred to as GFRP rebar, or simply fiberglass rebar) is a much more practical and forward-thinking choice. While GFRP rebar cost considerably more than black steel rebar, this thoroughly modern reinforcing material has a number of advantages that are well worth the extra cost:
One of the most well-known disadvantages of traditional black steel rebar is its vulnerability to rust and corrosion. Moisture that permeates through the pores of the concrete can cause rapid, damaging corrosion that can fatally weaken the reinforced concrete and cause catastrophic structural failure.
Many reinforced concrete structures with black steel rebar need to have their rebar replaced as little as every five years, which can be cripplingly expensive. Vinyl coated steel rebar is a better choice, but will only add a few years to the rebar's lifespan.
GFRP rebar completely avoids these issues as it is completely resistant to corrosion and will never weaken as a result of moisture exposure. When you consider that minor rebar replacement work can cost thousands of dollars, this makes GFRP rebar a fantastic long-term investment.
Excellent resistance to cyclic loading fatigue
The lifespan of black steel rebar can also be dramatically shortened by cyclic loading. This occurs when the weight a section of rebar has to support fluctuates frequently, which causes the rebar to flex under the weight and then rapidly rebound to its original shape.
Parking garages made from reinforced concrete are particularly vulnerable to cyclic loading. In a busy parking garage, an individual section of a reinforced concrete floor will have the weight of hundreds of cars pass over it in a single day. As you can imagine, this causes a significant amount of cyclic loading and can fatally damage the steel rebar within.
GFRP rebar is considerably more flexible than black steel rebar as well as other 'premium' rebar materials such as stainless steel. This gives it an incredibly high resistance to cyclic loading fatigue caused by passing vehicles and further increases the long-term durability of GFRP.
Black steel rebar also weighs a considerable amount, which can cause problems when constructing parking garages and other multi-story structures. To support the added weight of the steel rebar in the upper floors, the lower sections of a parking garage made from conventional reinforced concrete must be significantly strengthened, often at a considerable added cost.
GFRP rebar is many times lighter than black steel or stainless steel rebar and adds considerably less weight to the concrete it is used to reinforce. It is especially useful when used on the upper floors of parking garages and other multi-level structures, minimizing the extra load added to ground-level support structures.
For more information about GFRP rebar, speak with a professional.