Seismic Retrofit for Existing Buildings

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1 Seismic Retrofit for Existing Buildings

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3 1 Fasten building to foundation A) Epoxy USP offers CIA GEL7000-C epoxy that enables anchors for shear and tension loads to be installed at existing concrete foundations. B) Anchors Anchors such as, the THR series retrofit bolt and Wedgebolt offered by USP Structural Connectors provide the connection from the structure to the foundation to transfer horizontal (shear) and vertical (tension) forces from earthquake and wind loads USP-BP (Standard Bearing Plate) Lateral loads 2A 2B HFX-Series Panel Hardy Frame HFX-Series Panel in a Retro-Fit Application provides Strength, Stiffness and Ductility at an economical price. 3 USP-SRC (Sill Retrofit Connector) Angles - Joist to plate USP-MPA1 (Multi-Purpose Framing Angle) Hardy Frame Special Moment Frame The Hardy Frame Special Moment Frame provides maximum load resistance in narrow wall sections. The first standardized, pre-fabricated Moment Frame in the industry that requires no field welding and no field assembly. USP-MP34 (Framing Angle) USP-MP4F (Multi Purpose Plate Connector) Framing Angles provide structural connections at inside corners where floor or roof systems intersect with load bearing walls. Plate Connectors provide structural connections at flat surfaces for transferring forces between framing members.

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5 Epoxy CIA GEL7000-C epoxy has an ICC-ES evaluation report (ESR- 3609) for design in seismic categories A-F for use in cracked and un-cracked concrete. The engineer of records design will take into account concrete edge distances, end distances and the amount of combined tension and shear needed to resist the forces transferring from the Hardy Frame Shear Panel to the existing foundation. Epoxy Thru-Bolt The design, including capacity of existing concrete and size of Bearing Plates below is determined by the engineer of record. The adjacent illustration shows installation with a Hardy Frame Bearing Plate (HFXBP) at the underside of concrete. Thru-Bolt New Footing Below Hardy Frame unreinforced or reinforced anchorage solutions may be used below existing concrete or to replace existing concrete. New Footing Below Existing Panel Installation 1 1. Tilt Panel, lift over bolts and swing into the existing space 2. Install 2x filler at 1-1/2 cap 3. Connect with 1/4x4 USP WS-Series Screw 2 3

6 Installation inside an existing wall line 1. Dig footing for pads or grade beam per the Engineer of Records specification. 2. Tilt Moment Frame and lower the base plate of both columns into the trench prior to pouring concrete. 3. Rotate top of Frame until it is vertical, raise Frame up until the top of beam wood nailer is in contact with the existing framing above then temporarily shore the Frame in place. 4. Assemble the Template Kit as shown in Hardy Frame Details and the illustrations provided on the Template Kit packaging 5. Install all hold down anchors in the base plates 6. With specified reinforcement in place (not shown) pour concrete into footing up to the bottom of the column base plates. 7. At top of beam wood nailer install USP MP4F connectors to the existing collector above per the plan specifications by the Engineer of Record.

7 Installation outside an existing wall line 1. Dig footing for pads or grade beam per the Engineer of Records specification. 2. Assemble the Template Kit as shown in Hardy Frame Details and the illustrations provided on the Template Kit packaging 3. Locate assembled Template Kits at each of the column locations and orient the Template edges with the slotted holes in the same direction as the Moment Frame wall line 4. Measure the interior slot to slot distance to be the same as the Win (inside steel to steel) dimension for the Frame being installed. 5. Set the top of all anchors to be 4-1/4 inches (minimum) above top of concrete 6. With specified reinforcement in place (not shown) pour concrete into footing 7. Install one nut with one washer above on all anchors with the washers at approximately 1-1/2 inches above top of concrete 8. Install one washer in contact with the top of base plate and nut above 9. Level the Frame and make height adjustments by raising or lowering the nuts below the base plate. Check to be sure the pre-attached angle above the MF beam is in contact with the outside (or inside) face of wall per the plan specification by the Engineer of Record. 10. Install screws horizontally through the angle into the existing wood structure

8 Geological conditions and historical records of earthquakes help us to identify and classify high seismic zones. Earthquakes such as the 1971 San Fernando, 1987 Whittier, 1989 Loma Prieta, 1994 Northridge, and 2001 Nisqually Washington have caused extensive damage to thousands of wood-framed single family and multifamily homes. The resulting damage has helped to advance new products and methods that improve the structural integrity of existing buildings. This pamphlet provides an introduction for building owners in construction techniques and products available to provide connections that have been shown to improve a structures ability to resist earthquakes. MiTek Builder Products include Hardy Frame prefabricated Shear Walls and USP Structural Connectors that are designed to resist earthquake loads. These products are intended for installation in new construction or existing structures as a retrofit to improve the buildings ability to resist earthquake forces in order to provide safety and reduce damage. For buildings identified to need seismic strengthening, it is recommended that owners consult with a licensed professional engineer who is experienced and qualified in seismic design, and with a licensed contractor capable of performing the installations required. For help selecting a qualified engineer contact the Structural Engineers Association of California (SEAOC) at For walls with large openings such as garage doors, french doors and picture windows Hardy Frame Panels, Brace Frames and Special Moment Frames are specifically designed to add strength, stiffness and ductility. For structural connections throughout the building, including anchorage to the foundation, USP Structural Connectors offer a variety of steel products and applications to provide earthquake resistance where it is needed most. For all seismic retrofit applications please look to MiTek Builder Products for a complete line of economical structural components that are available from local building material suppliers. Call us today with questions or to request further information regarding seismic retrofit projects. Hardy Frames 1732 Palma Dr., Suite 200, Ventura, California (800) USP Structural Connectors Southcross Drive Suite 200, Burnsville, Minnesota (800)