ConXtech’s ConXL™ Bi-Axial Steel Connector has Been Formally Approved as a Special Moment Frame (SMF) Connection by the American Institute of Steel Construction (AISC)

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The AISC Connection Prequalification Review Panel (CPRP) includes ConXtech’s revolutionary building technology in the 2010 Seismic Design Manual.

“The ConXL system is the only one that has been specifically qualified by AISC for use in distributed biaxial framing systems." Ronald O. Hamburger, Senior Principal - Simpson Gumpertz & Heger (SGH)

ConXtech Inc. announced today that its ConXL structural steel connection has been formally prequalified as a SMF connection after an arduous review process conducted by the AISC 358 Connection Prequalification Review Panel (CPRP). ConXL will be Chapter 10 in the “Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications” section of the 2010 AISC Seismic Design Manual. Structural Engineers from around the globe look to AISC as the authoritative body on steel structures. The International Building Code (IBC) and local jurisdictional building codes adopt their seismic requirements based on AISC 341, Seismic Provisions for Structural Steel Buildings and AISC 358, Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications for seismic design and detailing.

ConXL offers design teams a robust yet simplified factory manufactured “lower and locking™” steel connection system. “In conventional steel structures, engineers incorporate a significant number of dissimilar and relatively complex steel connections within a building frame. Those connections are detailed and then handcrafted, cut and fit from a wide array of steel shapes and sections. They are then welded into the structure in the field. The more demanding the seismic or wind loading, the more complex that structure gets, and the more time consuming it becomes for the fabrication and construction teams to deliver,” states Robert Simmons, CEO of ConXtech. The ConX System utilizes the identical factory manufactured connectors redundantly throughout the structure delivering unprecedented robustness, quality and speed of construction. The company, which currently holds fifty patents on its building technologies, products and methods, has begun to make its technology available through a network of ConX Certified Fabricators.

This milestone is the most significant to date for ConXtech, which debuted its - ConXR™ system in a high-density residential structures at Santana Row in San Jose, CA in 2004. The company developed its longer span ConXL system in 2007 and built the first structure incorporating the ConXL connection in Santa Clara, CA in 2008. Both the ConXR and ConXL systems have been compared to a "Full-Scale Erector Set™" and both heavily depend on ConXtech's proprietary manufacturing technology to assure quality, precision and ease of assembly in the field.

Ronald Hamburger, Senior Principal at Simpson Gumpertz & Heger, the current Chairman of the AISC CPRP, temporarily recused himself from that position to serve as ConXtech’s “Representative Engineer” during this qualification process. “The ConXL system is the only one that has been specifically qualified by AISC for use in distributed biaxial framing systems. As such, it offers engineers the ability to design economical and highly redundant structures that offer superior seismic and progressive collapse resistance,” states Hamburger.

Over the past twenty-four months, ConXtech has completed six successful full-scale destructive tests of the connection system under an unprecedented bi-axial test protocol set by an AISC Connection Prequalification Review Panel comprised of twenty-one world class consultants, building officials, fabricators and academics. The bi-axial testing subjected ConXL to the typical Seismic Provisions cyclic loading protocol, while simultaneously subjecting the connection to a constant orthogonal load equal to 100% of the probable maximum moment (Mpr) of the primary beams. No other steel framing connection has been subjected to this type of loading -- the ConXtech connections are the only true bi-axial steel moment connections in the market today.

AISC’s CPRP reviews connection test data and other relevant research in its process to prequalify connections in accordance with the AISC Seismic Provisions. The connections that gain approval of the AISC CPRP reviews are considered a prequalified SMF connection standard. A moment connection prequalified by the AISC CPRP provides the most recognized and direct method of satisfying the Seismic Provision’s conformance demonstration requirements for SMF and IMF connections and greatly simplifies the project approval process.

About ConXtech Inc.
ConXtech Inc. is a building technology company based in Hayward, CA. The company has developed ConX®, a revolutionary structural steel building system which enables rapid delivery of robust, cost efficient and sustainable structures. The company sells a standard set of manufactured "lower and locking™" connectors and building components enabling the mass-customization of a precise structural building frame or "chassis" to which other factory manufactured building modules can be added. When assembled into multi-bay, multi-story structures, the patented connection technology delivers a brace-free grid of special moment frames ("SMF") ideal for commercial, healthcare, military, high-density residential, data center, educational, and industrial structures. The ConX System reduces time and overall project costs when compared to conventional structures and brings a systemic change to the building process, enabling owners and developers to predictably build "Faster, Better, Safer and Greener™". ConX SMF connections meet special detailing requirements for the most demanding seismic loading as well as the current U.S. Department of Defense anti-terrorism standards for blast and progressive collapse resistance. The ConXL™ SMF connection is approved by the Office of Statewide Health Planning and Development ("OSHPD") for use in California hospital facilities and has been prequalified by the American Institute of Steel Construction ("AISC") and published in AISC 358-10 Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications for use by structural engineers worldwide. ConXtech licenses its fabrication technologies, methods and processes to a growing network of certified fabricators and erectors. For more information about ConXtech, visit


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