1.8 Collapse Probability Assessment
Hospital owners may request a collapse probability assessment to reclassify buildings with an SPC-1 rating to SPC-2 in accordance with Section 126.96.36.199.2, or be used to determine eligibility for an extension in accordance with Section 1.5.2 Item 8.
MODEL BUILDING TYPE
|W1||Wood, Light Frame (≤ 5,000 sq ft)|
|W2||Wood, greater than 5,000 sq ft|
|S1||Steel Moment Frame|
|S2||Steel Braced Frame|
|S3||Steel Light Frame|
|S4||Steel Frame with Cast-In Place Concrete Shear Walls|
|S5||Steel Frame with Unreinforced Masonry Infill Walls|
|C1||Concrete Moment Frame|
|C2||Concrete Shear Walls|
|C3||Concrete Frame with Unreinforced Masonry Infill Walls|
|PC1||Precast Concrete Tilt-Up Walls|
|PC2||Precast Concrete Frames with Concrete Shear Walls|
|RM1||Reinforced-Masonry Bearing Walls with Flexible Diaphragms|
|RM2||Reinforced-Masonry Bearing Walls with Rigid Diaphragms|
|URM||Unreinforced-Masonry Bearing Walls|
The collapse probability assessment by the Office shall be determined using the following:
- Multi-Hazard Loss Estimation Methodology, Earthquake Module (HAZUS-MH) developed by the Federal Emergency Management Agency (FEMA)/National Institute of Building Sciences (NIBS).
- Building specific input parameters required by the Advanced Engineering Building Module (AEBM) of the HAZUS methodology shall be obtained from Appendix H to Chapter 6.
- Deterministic ground motion due to the maximum magnitude earthquake event on the controlling fault system.
- Probabilistic ground motion having 10 percent probability of being exceeded in 50 years.
The collapse probability assessment for SPC-1 buildings shall be based on the following building information, parameters and documents:
- Materials Tests: Office approved materials test results based on test plan preapproved by the Office (Section 2.1.2).
- Load path (Section 3.1)
- Mass irregularity (Section 3.3.4).
- Vertical discontinuity (Section 3.3.5).
- Adjacent buildings (Section 3.4).
- Short captive column (Section 3.6).
- Material deterioration (Section 3.7).
- Weak columns (Sections 4.2.8 and 4.3.6).
- Wall anchorage (Section 8.2).
- Redundancy (Section 3.2).
- Weak story irregularity (Section 3.3.1).
- Soft story irregularity (Section 3.3.2).
- Torsional irregularity (Section 3.3.6).
- Deflection incompatibility (Section 3.5).
- Cripple walls (Section 5.6.4).
- Openings (in diaphragm) at shear walls (Section 7.1.4).
- Topping slab missing (Sections 7.3 and 7.4) or the building type (structural system) is of lift slab construction.
- URM wall height to thickness ratio (Section 5.4.3).
- URM Parapets (Section 10.1.6).
- Building systems shall be classified as to their Model Building Type in accordance with Table 1.8. For buildings with multiple building types, all types shall be listed. The building type resulting in the maximum collapse probability will be utilized by the Office to determine eligibility for reclassification.
- Building height and number of stories above and below the seismic base shall be specified.
- A site plan showing diagrammatically the location of the building footprint, the surface trace or traces of potential surface fault rapture.
- The expected surface displacement during a rupture event.