Section 5-1: Structural Design Considerations
5-1-00 Design Requirements
10 Design Guidance
20 Design Information
30 Design Document Requirements
5-1-00 Design Requirements
A. Planning Module:
The laboratory planning module shall be considered the primary building module in multi-use facilities due to the importance of the laboratory-planning module to functional and safety issues.
Early planning and coordination of the entire design team is critical. Close coordination between structural and mechanical disciplines is critical to minimize interference of piping and ventilating systems with structural framing. Columns shall not fall within the laboratory-planning module to prevent interference with facility space planning and laboratory layouts, and inefficient use of valuable space.
B. Future Expansion:
Specific plans for future vertical or horizontal expansion shall be considered during the pro-gramming and planning stages, and accommodated during the design stage. Provision shall be made for the addition of future floors and additions as determined by the NIH on a project-by-project basis. Future expansion plans, including assumed type of construction and live loads shall be shown on the drawings. With a view to potential expansion of mechanical areas to adjoining roof areas, use the mechanical area design live load, for that roof area.
C. Equipment Pathway:
The potential routing or pathway for the addition or relocation of heavy equipment shall be identified during the planning phase, so that floor loading can be accommodated during the design phase. The pathway of heavy equipment shall be designated on the construction documents and designed to accommodate floor loading. Where there are occupied areas below grade extending beyond the exterior building walls above grade, the roof area of the below grade spaces shall be designed to support fire fighting equipment.
D. Structural Bay Size:
Both vertical and horizontal dimensions of the structural bay shall be carefully evaluated with respect to the laboratory planning module, mechanical distribution, and future expansion plans.
The horizontal dimension of the structural bay shall be a multiple of the laboratory-planning module dimension to provide for maximum flexibility and regular fenestration; and to allow uniform points of connection for laboratory services with respect to the laboratory-planning module.
E. Geotechnical Report:
The geotechnical report prepared by a registered geotechnical engineer, shall include test borings in soil, and rock coring, if rock is encountered and provide information as to the types of soil encountered, allowable bearing pressures, differential and absolute settlements, lateral soil pressures, suggested types of foundations, water table, drainage requirements, preliminary recommendations for sheeting and shoring, and special foundation problems. The geotechnical report shall be included in the construction documents. The geotechnical engineer shall be retained to prepare a comprehensive geotechnical investigation (report) prior to structural foundation design, verify materials encountered during construction, and monitor earthwork operations.
F. Level of Concrete Finished Floors:
Unless otherwise specified, a concrete floor shall be level, ±3 mm in height in 3 050 mm in any direction, measured at any point of the floor. Floor flatness (FF) and floor levelness (FL) numbers shall be specified when the installations of finish materials, functional conditions, or equipment dictates tight control to assure top slab surface is constructed, essentially, “dead-level.
G. Post-tensioned Concrete:
Inadvertent cutting of post-tensioned concrete is a safety hazard, and if cut, steel strands may eject from the ends of the tubes into which they were placed or otherwise create danger to personnel. No holes shall be cored or other demolition shall occur prior to locating tension strands by conducting ground-penetrating radar and/or pacometer testing, and recorded under the supervision of a registered structural engineer. Information is to be provided to the A/E for designing a procedure under which the demolition work is to be done and demolition is required to be performed under A/E’s supervision.
H. Column Lines:
Indicate column lines, and coordinate that Architects and other disciplines, indicate the same on all plan views.
I. Graphic Scales:
Provide graphic scales on all plan view and section view drawings to assist readers with reduced size drawings.
5-1-10 Design Guidance
A. Structural System:
The structural system for NIH facilities includes subsystems’ specific performance requirements as follows:
The foundation system shall be of sufficient size, rigidity, and strength to resist all imposed loads without deflection or settlement that would result in damage to any building systems or affect the facility’s operations.
A.2 Grade Level Framing:
Slab and grade beam bottoms, may be supported by site soils if subsurface conditions are acceptable based on a geotechnical investigation.
A.3 Foundation Walls:
Basement and foundation walls shall consist of cast-in-place concrete with control joints at 6.1m maximum spacing, with construction joints at 12.2m maximum spacing to minimize cracking.
A.4 Columns, Beams, Girders, Concrete Pan Joist, Steel Joist, Concrete Slabs and Steel Decking:
Typical, acceptable structural framing may consist of concrete framing, steel framing, concrete for lower levels and steel framing at higher levels depending on the research to be conducted. Buildings that will house vibration-sensitive research require evaluation of the framing system prior to selection, by a vibration consultant acceptable to the NIH, for compatibility with the research equipment vibration limitation tolerances.
A.5 Lateral Load Resisting System:
The lateral load resisting system shall be selected to provide the stiffness required with a minimal impact on facility operations while providing for the highest redundancy. Moment resisting frames, braced frames, or shear walls are preferred.
A.6 Secondary Structural Support:
Secondary structural support for equipment shall consist mainly of structural steel framing hung from the structure above, supported by posts from the floor below, or bracketed off adjacent walls, as reviewed and approved by the vibration consultant. The design of secondary structural supports shall consider the movement, vibration, maintenance, and seismic forces related to each element supported.
A.7 Bracing of Non-Structural Items:
Architectural, mechanical, and electrical components shall be designed and anchored to resist seismic forces in accordance with latest edition of the IBC.
B. Animal Research Facilities Structural Planning:
B.1 Structural Bay Size:
Both vertical and horizontal dimensions of the structural bay shall be carefully evaluated with respect to the functional requirements of animal facility spaces, the primary building module, mechanical distribution, and future expansion plans.
The horizontal dimension of the structural bay shall be a multiple of the planning module or primary building module dimension for maximum flexibility, and to allow uniform points of connection for animal research facility services.
The A/E shall attempt to locate animal research facilities on grade-supported slabs, so as to reduce vibration concerns, easily accommodate pits required for cage and rack processing, and eliminate the risk of water leakage to lower levels.
Because vibration transmission adversely affects research, impact driven shoring systems shall not be used, unless the contract specifically states this system may be used. Also see DRM Section 6-5 Noise and Vibration.
B.4 Floor Slab Depressions:
Floor depressions and/or topping slabs shall be evaluated for use in special-finish areas, wet areas, or areas exposed to materials that may deteriorate the structural floor slab. Floor depressions shall be reviewed for equipment requirements to allow for ease of movement of equipment. Floor slabs shall slope to accommodate drainage, and pits shall be provided in cage wash areas. Suitable protection of the concrete and reinforcing shall be considered in high-temperature cage wash areas, and areas employing salt water in conjunction with their research.
Security level of design for all biomedical laboratories and animal research facilities shall result from project specific risk assessment. The A/E shall use the existing baseline Threat Assessment, provided by DPSM, for the preparation of an updated Threat Assessment.
C.1 Progressive Collapse:
Progressive collapse resistance shall be considered in the structural design of the facility and provided in accordance with GSA design requirements.
Prevention of Progressive Collapse: The project manual shall require the A/E to indicate and specify, if and where expansion anchors will be used in tension on the project. The A/E shall indicate the “maximum load” that type of anchor will be required to carry in tension. The Construction Contractor shall initially test at least one of ten of those anchors, randomly selected by the NIH. A device, of the Contractor’s design, shall suspend a load from each of the designated anchors. The load shall be 3 times the “maximum load” and left for 24 hours. The contractor shall record the results and provide a copy of the report to the NIH. If a test anchor fails to maintain the installed status, more anchors shall be tested to the satisfaction of the project engineer that the anchors are safe.
D. Use of Recycled Materials in Concrete:
The NIH encourages the use of recycled materials in concrete if cost effective and unless a product is not available competitively within a reasonable timeframe or does not meet appropriate performance standards. Concrete containing coal fly ash or ground granulated blast furnace slag can be considered for NIH projects, EXCEPT in animal facilities.
5-1-20 Design Information
A. General References:
During the planning and design phase, the most cost-effective, functional and aesthetic structural design should be developed. NIH campus buildings should meet all current building codes and ordinances. These include, but are not limited to, the latest editions of the following:
• International Building Code, International Code Council, 5203 Leesburg Pike, Suite 708, Falls Church, VA 22041-3401
• Building Code Requirements for Reinforced Concrete, ACI 318, American Concrete Institute, Detroit, MI
• Manual of Steel Construction ASD, American Institute of Steel Construction, Chicago, IL
• Building Code Requirements for Masonry Structures, ACI 530; and Specifications for Masonry Structures, ACI 530.1, American Concrete Institute, Detroit, MI
• Minimum Design Loads for Buildings and Other Structures, ASCE 7, American Society of Civil Engineers, New York, NY
• National Design Specification for Wood Construction; and National Design Specification Supplement, National Forest Products Association, Washington, DC
American Concrete Institute publications provide the de-facto project standards regarding reinforced concrete.
5-1-30 Design Document Requirements
A. Structural Plans (Design Development and Contract Documents)
Floor framing plans, sections, roof framing plan, roof penetration details, column and beam schedules, miscellaneous details, and cover sheet requirements.
B. Specifications (Outline and Detail Performance Specifications)
Outline specifications shall be developed at the design development stage and detail performance specifications shall be developed at the contract document stage.
C. Cost Estimates (Systems and Quantity Takeoff Estimates)
Systems cost estimates shall be developed at design development stage and quantity take-off estimates shall be developed at the contract document stage.