Introduction to BauGrid®

The BauGrid Reinforcing system is a welded reinforcement grid (WRG) which can be used in lieu of conventional transverse reinforcing in concrete structures. It is manufactured from high strength cold drawn wire (75Ksi) conforming to ASTM A82. It is manufactured in accordance with ASTM A185 from wire of 3/8", 1/2", 5/8" & 3/4" diameters within a tolerance of +/- 1/8"

The BauGrid is a proprietary reinforcing product patented in Canada, EU and Japan and the United States (US Patent No. 5,218,809 & 5,392,580).

Introduction to Delta Building Systems

Our company, Delta Building Systems (DBS) has an exclusive license from BauTech to manufacture and distribute the BauGrid® reinforcing system in North America and Asia. DBS has custom designed and invested in all of its equipment, using the latest technology. Currently 6-250KVA welding systems are in operation in Asia with an annual capacity of over 4000 tons.

Our facility is audited by Smith Emery Laboratories of Los Angeles on a quarterly basis.  DBS’ manufacturing associates and sub-licensees and suppliers have been selected through rigorous evaluation by DBS Q/C team. They maintain the highest levels of experience and qualification in the welded wire industry and meet or exceed standards set out by ICC, ISO and BauTech.

DBS plans to increase production capacity in Asia to 8000 tons by the end of this year. In addition to doubling the Asia capacity, DBS is in process of establishing a local (San Diego, CA) manufacturing plant with production anticipated in the final quarter of this year.

BauGrid & Concrete Construction

The BauGrid is ICBO approved under the ICC –ES Legacy Report no. ER-5192. We are currently in process for conversion to the new ICC-ES as required by ICC Rules of Procedure. For over 15 years this systems has been used as transverse reinforcement in shear walls, columns and beams of many mid and high rise concrete structures. In that period of time it has been understood that BauGrid provides a reinforcing solution that can both improve structural performance and constructability.

Particularly with respect to Seismic engineering, there have been a number of studies and papers written that indicate the importance of reliable ductility in the design of earthquake resistant reinforced concrete structures. On that point, there are a number of tests undertaken which show reinforcement with BauGrid have significantly increased ductility of the concrete structures over reinforcement with conventional hoops and cross ties. [For example the tests performed on a column-beam joint at NIST showed the conventionally reinforced column and beam joint failed at 3% story drift, which the hybrid component reinforced with BauGrid was able to withstand a 6% drift with only cosmetic damage.] [1]

From an Environmental and practical standpoint the fundamental design concept of a welded reinforcement grid (WRG), a BauGrid, replacing conventional hoops and crossties, automatically reduces the quantity, or weight, of steel required to achieve the engineer’s design goal.  Each length of end hook for ties, stirrups and hoops determined by the standards outlined in [2] is replaced by a simple welded connection.  Depending on the complexity of the reinforcement layout and the size of the wire, substitution can constitute a 20-50% reduction in material.

In addition, each grid represents a layer of transverse reinforcing that would have required assembly in the field, effectively "pre-fabricating" the assembly.

From this Constructability perspective, the fixed and uniform nature of the layers of transverse reinforcing inherent to BauGrid, also results in a reduction of labor required to assemble cages. The additional benefit of this more uniform and fixed assembly lies in the installation of the cages. The "cork-screwing" of cages in the field is all but eliminated with the use of BauGrids, allowing more flexibility for field crew to determine installation logistics and thereby reducing crane time required for installation of cages.

BauGrid Projects

DBS is currently supplying BauGrid for the entire core walls, frame columns and beams of the 60-story Millennium Towers in San Francisco, as well as 2 18-story and (1) 12-story structures in San Diego where BauGrid is replacing conventional reinforcing in the boundary elements of the shear walls.

Due to the nature of the product the BauGrid provides a solution to an increasingly common constructability issue for heavily congested concrete structures. The taller the structure, the more reinforcement required by code, and the more applicable the BauGrid is as a reinforcing solution. In small low rise reinforced concrete, the simple cage construction does not always merit the higher unit weigh cost of a BauGrid.  In this cost comparison it is our intent to focus on the concrete (division 3) costs of high rise concrete structures.

The BauGrid has been approved for use in California with projects constructed in Los Angeles (Los Angeles Research Report RR-2438), San Francisco, San Diego, Long Beach, Oakland and Daly City.  The BauGrids have also been approved and used in projects across the U.S.; in Phoenix (AZ), Eugene (OR), Long Island (NY) and Kauai, (HI).

Testimonials

BauGrid has an established clientele of Specialty Sub-Contractors, General Contractors, Engineers, Architects and Owner/Developers. Within each of these industry echelons, there are advocates of the BauGrid system and testimonials of the benefits of implementing the system:

• The rebar subcontractor benefits reduction of time and labor in rebar cage assembly and installation.
• The concrete subcontractor benefits by reduction of time and labor during form installation and concrete placement due to uniform and fixed cages and reduction in rebar congestion that allows for easier vibrator access. The improved vibration access reduces "honeycombing" which in turn reduces the need for patching.
• The general contractor benefits by lower crane time and improved schedule adherence.
• By incorporating the system at the design phase, the engineer and architect can benefit by increasing their design flexibility and controlling their owners cost of construction.
• The owner benefits by increased construction speed and thus earlier tenant occupancy. In the event of an earthquake there are indications that an owner will also benefit from reduced repair costs under such seismic stress.