As building tenants change, so does the loading requirements of the existing structure. For some building owners this may be as simple as increasing structural capacity in the joists, beams, and columns. For others is a complete change of use by removing a part of the existing slab to install a stairwell to connect the 10th and 11th floor. Every one of these projects have unique needs, designs, and specifications that will be specific to the new tenant needs. One major need is updating the floor when a high density file system is added for the tenant.
Delta’s design and construction team will create the most cost effective and minimal impact construction to meet those needs. Normal strengthening with conventional steel beams involves cutting the beams in pieces to take them up the building and feeding through window openings. The pieces are then reassembled with full penetration welding and attached in place below the slab. This can take many weekends in an occupied space. The Delta system using carbon fiber for strengthening and fire coating with a 2-4 hour UL rating can usually be accomplished over a long weekend starting Friday and ending by open of business Monday morning. By combing over 30 years of construction deliverables and time proven design, we welcome the most complex building issues.
There are also times when the upgrades are needed to solve many problems such as corrosion or loss of structural strengthening. The most common deterioration mechanisms observed within high-rise residential, hotel and institutional buildings are associated with cracking due to a constrained change in volume, corrosion of reinforcing steel or balcony posts, and failed / aging protective coatings. Cracks originating from shrinkage cracking, balcony post embedments, and failed protective coatings expose vital reinforcing steel to chlorides and moisture present in the environment. Although the alkaline environment of concrete protects reinforcing steel by formation of a passive layer above a PH of approximately 10, this passive layer will be compromised by the introduction of chlorides or the lowering PH effect on concrete known as carbonation. Delta provides solutions for protection and maintenance of reinforced concrete structures in addition to repair services. Often, a combination of protection and repair are needed to ensure long term durability of the structure.