CONTACT US TECHNICAL SUMMARIES: CONXL AISC PRE-QUALIFIED CONNECTION SMF CONNECTION

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1 CONXL AISC PRE-QUALIFIED CONNECTION ConXtech s ConXL connection has been through a rigorous qualification review process conducted by the AISC Connection Pre-qualification Review Panel (CPRP). ConXL was approved through this process and has been incorporated as Chapter 10 in the 2010 AISC 358 code book, Pre-qualified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications. ConXtech completed six successful tests of its moment connection for the CPRP under the unprecedented bi-axial test protocol which subjected the ConXL connection to the typical Seismic Provisions cyclic loading 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 as the ConXtech connections are the only standard bi-axial steel moment connections in the market today. SMF CONNECTION AISC s CPRP reviews connection test data and pre-qualifies connections in accordance with the AISC Seismic Provisions. The connections that gain approval of the AISC CPRP reviews are considered a prequalified connection standard. A moment connection pre-qualified 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 simplifies the project approval process for this class of buildings.

2 BI-AXIAL TEST FRAME ConXtech s unique Bi-Axial Test Frame was developed to satisfy the conformance demonstration requirements for a bi-axial SMF connection that may be required for pre-qualification in any jurisdiction. The ConX moment connection is the only standard bi-axial connection that exists in the steel framing market today and due to its unique characteristics, a new testing protocol was developed and approved by the California Office of Statewide Health Planning and Development (OSHPD). These new conformance requirements are unprecedented with testing conditions no other steel moment connection has ever been subjected to. ConXtech s Bi-Axial Test Frame is unique in its capability of cyclically testing (in the primary direction) a single column and two moment beams, up to a W36x262, while simultaneously imposing an orthogonal load across secondary moment beams equivalent to the primary beams probable maximum moment (Mpr). The self-equilibrating frame has the capacity of imposing, along the primary axis, a 1,000 kip load at the top of column while resisting 700 kip reactions at beam ends; and along the secondary axis, impose 700 kip loads at beam ends while resisting a 1,000 kip reaction at top of column.

3 CONXL OSHPD APPROVAL PROCESS The ConXL connection is qualified as a Special Moment Frame connection for use in hospital environments with the California Office of Statewide Health Planning and Development (OSHPD). OSHPD observed the successful completion of three full scale bi-axial tests, which met OSHPD s test protocol designed specifically for ConXtech s connection. ConXtech also completed 3 additional tests following this protocol for AISC CPRP qualification. This qualification is unique as no other steel moment frame has undergone cyclic testing while simultaneously being subjected to a constant orthogonal load equal to 100% of the probable maximum moment (Mpr) of the primary beams. This unprecedented bi-axial testing proved the unique capabilities of the ConXtech moment connection, the only standardized true bi-axial moment connection in the steel framing market today.

4 CONXTECH TEST FRAMES Bi-Axial Test frame Single Axis Test frame ConXtech has two in-house test frames capable of qualifying cyclic tests of beam-to-column connections per the Seismic Provisions. ConXtech s bi-axial test frame is capable of qualifying cyclic testing about the primary axis, while simultaneously imposing an orthogonal load across the secondary axis. ConXtech s single axis test frame can test moment beams up to a W30x99, while its bi-axial test frame can test up to a W36x262. These test frames provide ConXtech with unparalleled access to efficient and cost effective testing for project specific requirements.

5 RESISTANCE TO PROGRESSIVE COLLAPSE The terrorist attacks of 1995 (Murrah Federal Building) and 2001 (World Trade Center) focused attention on structural design requirements to prevent the catastrophic damage caused by these events. However, creating practical design requirements for such severe loading proved to be an extremely difficult task. Because prescriptive and performance requirements for blast and progressive collapse mitigation do not appear in the design codes, they are not codified into law. The owner, architect and structural engineer are the key stakeholders who carry the responsibility in deciding if the need for blast and progressive collapse resistance is necessary. Generally prescriptive design procedures for blast and progressive collapse resistance result in inefficient costly construction and limitations on the architectural design of such buildings thus are rarely implemented on a project that doesn t have GSA, DoD or State Department requirements. In 2004, Ronald Hamburger of Simpson Gumpertz & Heger wrote an article (1) discussing the high costs and architectural limitations of current prescriptive design methods. He felt there was a much more cost effective performance based design method, but the industry needed a program of research and development similar to that conducted after the 1994 earthquake to determine the types of connection technologies that can be effective in resisting progressive collapse so that less conservative but more reliable approaches to blast-resistant design can be adopted by the community. ConXtech s ConXR framing connection debuted in 2004 and the ConXL connection in With the ConX System, the key stakeholders now have the option of specifying a structural framing system that will carry gravity, wind and seismic loading and also provide resistance to blast and progressive collapse, all in one efficient structural framing system. The innovative and highly robust ConX framing system provides a cost effective and easily configurable biaxial moment frame connection that also provides blast and progressive collapse resistance. In 2009 Ronald Hamburger wrote a paper (2) on the ConX connection in which he stated: The ConXR and ConXL systems are ideal for building applications that must be designed to resist progressive collapse resulting from vehicle impact, incendiary or explosive device attack. (1) Design of Steel Structures for Blast-Related Progressive Collapse Resistance Modern Steel Construction, March Ronald O. Hamburger, Simpson Gumpertz & Heger -Andrew Whitaker, University at Buffalo, NY (2) The ConX Connection: A Bolted Special Moment Frame Connection for Seismic and Structural Integrity Applications March Ronald O. Hamburger, Simpson Gumpertz & Heger