
MANDATORY SEISMIC RETROFITTING REGULATIONS
Recently Los Angeles adopted new regulations for a mandatory seismic retrofit of all pre-1978 wood frame soft-story buildings and all non-ductile concrete buildings. The goal of the mandatory retrofit programs is to reduce the structural deficiencies and improve the performance of these buildings during earthquakes. Without proper strengthening, these vulnerable buildings may be subjected to structural failure during and/or after an earthquake. We estimate there to be approximately 50,000 structures within Los Angeles that will be affected by these new regulations.
Together, with our partnerships and resources we can help to reduce the structural deficiencies by the most economical and feasible method. Don't delay!! Finding a qualified design build contractor and/or engineer will grow increasingly more difficult the closer we get to the mandatory deadlines. Surrounding LA cities are also beginning to adopt similar retrofit regulations to ensure seismic safety standards are met.


Soft-Story Retrofit
From the past earthquakes, multi-story buildings with weak and/or open front wall lines creating "soft-story" (i.e. buildings with tuck-under-parking) performed poorly and collapsed. The goal of the mandatory retrofit program is to reduce the structural deficiencies by the most economical and feasible method without proper strengthening, these vulnerable buildings maybe subjected to structural failure during and/or after an earthquake. Buildings that are within the scope of these new ordinances and require retrofitting are:
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Consists of 2 or more stories with wood frame construction.
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Built under building code standards enacted before January 1, 1978.
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Contains ground floor parking or other similar open floor space.
Non-Ductile Concrete Retrofit
From the past earthquakes, many concrete buildings constructed prior to the 1976 Los Angeles City Building Code previsions, or similar era codes in other countries, performed poorly and collapsed, causing loss of human life, personal injury, and massive property damage. The poor performance of these older concrete buildings is due to deficiencies in the lateral force-resisting system that render the building incapable of sustaining gravity loads when the building is subjected to an earthquake.
Buildings that are within the scope of these new ordinances and require retrofitting are:
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Concrete buildings with a roof and/or floor supported by a concrete wall or concrete column, constructed before January 13, 1977.
What Are The Solutions?
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AddingSteel Special Moment Frames, concrete footing & drag line.
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Cantilevered Column Solutions
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Updated Concrete or Plywood Shear Walls
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Adding Continuity Ties
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Replacing Existing Support Columns


What Are The Solutions?
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Steel Special Moment Frames
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Polymer or Carbon Fiber Wraps
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Steel Beam Installations
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Adding Concrete Shear Walls

