final_SOW_GravityLoadingandBracingSystem.docx

Statement of Work/Specifications Gravity Loading and Bracing System

Background The National Fire Research Laboratory (NFRL) at the National Institute of Standards and Technology (NIST) provides the capability to test full-scale building structures under hydraulically applied loads and realistic fire conditions. The facility is a unique National resource for large-scale structural-fire tests to validate computational models used to predict building performance in fire. The facility allows researchers to study the response of the full structure to fire, rather than the response of individual building elements or subassemblies as is the case in current practice. Research conducted in this facility will help to provide the technical basis for improvements to codes, standards, and design of building structures for fire.

Objective The purpose of this acquisition is for the fabrication of structural steel Gravity Loading and Bracing System to be delivered to the NFRL located in Building 205 at NIST in Gaithersburg, MD. The system will provide the capability to safely apply vertical forces to the tested structure while subject to a fire. The gravity loading system will allow the safe load transfer from the hydraulic actuators in the lab basement to the top of the tested structure; the bracing system will provide the safe anchorage of the loading structure to the strong floor of the NFRL. The components of the system include cross-beams, loading triangular spreaders, swivels, loading tubes, bracing modules, columns, and other specialized accessories. These components are described in more detail in Section 3.2. NIST will provide design drawings for the system components. Fabrication tolerances on the specified dimensions are critical to ensure compatibility with the existing components, and to ensure that the system can be assembled together as required. Acceptance of the components will be based on demonstration that tolerances are adequate for the system to perform as intended.

Specific Requirements Summary The Contractor shall provide the equipment, materials, and labor necessary to fabricate the system’s components and deliver them to the NFRL in Building 205 at NIST in Gaithersburg, MD. All structural steel components shall be fabricated in accordance with the following standards:

1. American Institute of Steel Construction (AISC) Specification for Structural Steel Buildings (ANSI/AISC 360-16)

2. American Society for Testing and Materials (ASTM) Standard Specification for General Requirements for Rolled Structural Steel Bars, Plates, Shapes, Sheet Piling (ASTM A6-17a)

3. American Welding Society (AWS) Structural Welding Code – Steel (AWS D1.1/D1.1M:2015)

4. Research Council on Structural Connections (RCSC) Specification for Structural Joints Using High-Strength Bolts (2014)

5. Research Council on Structural Connections (RCSC) Code of Standard Practice for Steel Buildings and Bridges (AISC 303-10) Different components of the system are sketched in Figure 1 and Figure 2. Detailed drawings, including dimensions and materials, are provided in Appendix A. Quantities, special remarks, and drawing numbers, for all components are detailed in Section 3.2.

Figure 1: Sketch showing some main components of the gravity loading system

Figure 2: Sketch showing some main components of the bracing system Table Table lists submittals that are required by this statement of work, as specified in Section 3.4. Performance requirements for the components are described in Section 3.3, quality assurance requirements are specified in Section 3.5, and materials are specified in Section 3.6.

Table 1 – Required submittals

1Required as part of the initial quotation submission

As indicated in Table Table , the Contractor shall provide two of the required informational submittals (documentation of qualifications and documentation of past performance) as part of the initial quotation submission. These submittals will be considered as part of the selection criteria for the award of the contract, and they shall demonstrate that the quality assurance requirements specified in Section 3.5 are met by the contractor. Requirements for fabrication are specified in Section 3.7. As specified in Section 3.7.1, this project requires exacting fabrication tolerances to ensure compatibility with existing systems and components, and can be assembled together as required into relatively complex test setup configurations.

The Contractor shall provide shop (erection) drawings of the system designed by NIST. Modifications to the initial design proposed by NIST are allowed, if the design revised by the Contractor meets the performance requirements. However, the overall dimensions are critical for the system to perform as intended and should not be modified without written approval from NIST. Revised design must be justified by contractor and approved by NIST.

The Contractor shall follow the process related to delivery, storage, and handling as specified in Section 4.

NIST will inspect each component for damage upon delivery and evaluate the fabrication tolerance as specified in Table 2 and in Section 5.

Table 2 – Inspection and evaluation requirements for acceptance of SRFs

Components and Detailed requirements The following Sections 3.2.1 through Section 3.2.11 provide a description of the different components, along with the quantities needed, and a reference to the drawing number. The drawings are attached in Appendix A, and provide details on the sections, dimensions, and other technical information for each component.

Item 1: Cross Beam Quantity = 6 Drawing A7 The cross beams will allow the transfer of the load that is applied at its mid-span to the loading triangular spreaders (Item 2). It will attach to the triangular spreaders via swivels (Item 3). The hole patterns on Item 1 (where the swivels attach) must match the hole pattern on the corresponding swivels (Items 3 and 4). The hole patters on Drawing A7 are for reference to where the swivels are supposed to attach.

Item 2: Loading Triangular Spreader Setup Quantity = 12 Drawings A3-A6 The triangular spreaders are built up from multiple HSS steel sections as shown in Drawing A2 through Drawing A6, and have half sphere bearings at the vertices. They will allow equal distribution of the load that is applied at their center of gravity (from the cross beam (Item 1)) onto the tested specimen. The hole patterns on Item 2 (where the swivels attach) must match the hole pattern on the corresponding swivels (Items 3). The hole patters on Drawings A2 through A4 are just for reference to where the swivels are supposed to attach.

Item 3: Swivel A with Top Bearing Plate Quantity = 8 Drawing A11 The swivels with top bearing plates will act as the bearing support and point of load transfer between the cross beams (Item 1) and the triangular spreaders (Item 2). The swivels allow large in-plane rotation (hinge support action), and also allow limited out-of-plane rotation to accommodate the deformation of the tested structure during the test. They must allow an in-plane rotation movement (angle “a” on drawing) of at least +/- 60o, and an out-of-plane rotational movement (angle “b” on drawing) of at least +/- 15o, as per attached drawings. They should be rated to carry a load of at least 32 Kips (in tension or compression), if off-the-shelf swivels are chosen. Custom-designed swivels that meet the requirements described above will be accepted. However, detailed design calculations must be provided and approved by NIST.

Item 4: Swivel B with Rod End Receiver Quantity = 4 Drawing A11 The swivels with rod end receivers will be the loading point on the cross beams (Item 1) transferring the load from the loading tube (Item 5). The swivels allow large in-plane rotation (hinge support action), and also allow limited out-of-plane rotation to accommodate the deformation of the tested structure during the test. They must allow an in-plane rotation movement (angle “a” on drawing) of at least +/- 60o, and an out-of-plane rotational movement (angle “b” on drawing) of at least +/- 15o, as per attached drawings. They shall be rated to carry a load of at least 32 Kips.

Item 5: Loading Tubes Quantity = 36 Drawing A8 The loading tubes will transfer the load from the hydraulic actuators in the lab’s basement to the cross beams (Item 1). It will attach via couplers (Item 6) to the swivels (Item 4).

Item 6: Couplers Quantity = 6 Drawing A9 The couplers will allow the attachment of the upper end of the loading tubes (Item 5) to the loading swivels (Item 4) via threaded rods (Item 7). They will have a drain to allow the flow of chilled water in the loading tubes during testing at elevated temperatures.

Item 7: Threaded Rods Quantity = 6 Drawing A9 The threaded rods will attach the couplers (Item 6) to the swivels (Item 4).

Item 8: Bearing plates Quantity = 126 Drawing A10 The bearing plates will be the contact point between the spherical bearings on the triangular spreaders (Item 2) and the test specimen.

Item 9: Washer Plates and Nuts Quantity = 6 Drawing A9 The washer plates and nuts will attach the lower end of the loading tubes (Item 5) to the existing actuator head couplers in the lab’s basement. 6 washer plates, and 6 nuts are needed.

Item 10: Bracing Modules Quantity = 4 Drawings B1, B2 The bracing modules will anchor the loaded structures to the lab’s strong floor via the anchoring columns (Item 11) during the test.

Item 11: Anchoring Columns Quantity = 2 Drawing C1 The anchoring columns will attach the bracing modules (Item 10) to the lab’s strong floor.

Performance Requirements Tolerances Tolerances for the different components are listed in Error! Reference source not found. in Section 3.7.1.

Surfaces All structural steel members shall be cleaned and surfaced by removing all loose mill scale, loose rust, loose paint, and other loose detrimental foreign matter by power wire brushing, power sanding, power grinding, power tool chipping, and power tool descaling. Surfaces are then to be coated with a minimum of one coat of shop primer.

Required Submittals Action Submittals Shop (Erection) Drawings: The contractor shall provide shop (erection) drawings of all components. The shop (erection) drawings shall:

1. Include development of accurate, detailed dimensional information to provide fit-up of all components.

2. Indicate plan views, elevations, dimensions, shapes, and cross sections of each component.

3. Indicate welded connections by American Welding Society (AWS) standard symbols. The weld design specification shall include the specification of the weld type/process and consumable, size and length of the weld, edge preparation, weld contouring and tolerances, and required inspection.

Shop (erection) drawings shall be produced using an electronic format such as AutoCAD or equivalent, and shall be submitted to NIST for review and approval. Drawings will be returned to the fabricator within 14 days. If required, the fabricator shall make all corrections noted by NIST and furnish revised shop (erection) drawings.

Informational Submittals A Documentation of Qualifications: The fabricator (contractor) must be certified through the American Institute of Steel Construction (AISC) as a Certified Building Fabricator (BU, formerly STD). Fabricators also meeting AISC’s bridge certifications (Certified Bridge Fabricator – Simple (SBR), Certified Bridge Fabricator – Intermediate (IBR), and/or Certified Bridge Fabricator – Advanced (ABR)) are preferred. The contractor must provide documentation of all AISC certifications. They shall provide documentation to verify the required qualifications specified in Section 3.5 (“Quality Assurance”)., and provide this documentation of qualifications as part of the initial quotation submission.

B. Welding Certificates: Copies of certificates for welding procedure specifications (WPS) and shop and/or personnel certification(s).

Quality Assurance

B. Design Standards: Comply with the AISC Code of Standard Practice for Steel Buildings and Bridges (COSP), which sets forth criteria for the trade practices involved in steel buildings, bridges and other structures.

C. Quality-Control Standard: For quality control recommendations for the types of SRF components required by this performance statement, comply with 2016 AISC Code of Standard Practice for Steel Buildings and Bridges (COSP). Must comply with dimensional tolerances specified in Section 3.7.1, which are more exacting than those specified in the 2016 AISC Code of Standard Practice for Steel Buildings and Bridges (COSP).

D. Welding: Qualify procedures and personnel according to the American Welding Society’s Structural Welding Code – Steel (AWS D1.1/D1.1M:2015).

Materials Rolled Structural Shapes, Steel Plates, Steel Tubes

Weld A. Welding Electrodes: Comply with the requirements of the American Welding Society’s Structural Welding Code – Steel (AWS D1.1/D1.1M:2015) for steel type and/or alloy being welded.

Fabrication Fabrication Tolerances As noted in Section 3.1, this project requires exacting fabrication tolerances. Fabricate components, so each finished member shall comply with the tolerances specified in the relevant ASTM specification for component dimensions, center-locations and diameters of holes, dimensions of cutouts, and locations/positions of components in welded assemblies, flatness, planeness, rightness.

Delivery, Storage, and Handling The Contractor shall coordinate with the NIST POC for delivery of the system to the NFRL at NIST, Gaithersburg. Delivery terms shall be FOB DESTINATION. The NFRL is directly accessible through a rollup door. NIST staff will unload the components from the delivery truck(s) inside the NFRL using the overhead crane and/or forklift(s). The Contractor shall comply with the following requirements for Handling, Storage, and Delivery of the system.

Evaluation and Acceptance NIST staff will inspect each delivered component for acceptance. Components that do not comply with the standards listed in Section 3.1, or that do not meet the tolerances specified in Section 3.7.1, are unacceptable. Additional requirements for inspection, evaluation, and acceptance are specified in the following.

Evaluation of Fabrication Tolerances To evaluate whether the fabrication tolerances are adequate for the system to perform as intended, two different sets of procedures will be employed wherever applicable, as outlined in Section 5.1.1.

Measurement of Dimensions, Flatness, and Levelness Selected critical measurements of the components will be taken as specified in the following. Deviations in these measurements that exceed the fabrication tolerances specified in are unacceptable. Certain unacceptable deviations may be corrected by grinding (see Item B1 in Section 5), but only provided that the extent of grinding is approved by NIST and will not impair the structural adequacy, serviceability and durability of the component.

Schedule The Contractor shall deliver all products and services in accordance with the schedule specified in Table Table . All dates are specified in calendar days.

Table 3 – Project schedule

First Submittal to NIST:

1. Comprehensive shop (erection) drawings (Section 3.4.1, Item A) 30 days after date of award

Second Submittal to NIST:

1. Comprehensive shop (erection) drawings (Section 3.4.1, Item A) 14 days after date of award

Delivery of the Gravity Loading and Bracing System to NIST:

1. All assemblies and components

2. Product quality-control data (Section 3.4.1, Item F)

3. Welding certificates (Section 3.4.2, Item C)

4. Material certificates (Section 3.4.2, Item D) 180 days after date of award

NOTE: Shaded rows indicate required approvals by NIST.

General Information Safety: Contractor employees shall be responsible for knowing and complying with NIST installation safety prevention regulations. Such regulations include, but are not limited to, general safety, fire prevention, and waste disposal.

Security: NIST is a restricted campus. An identification badge is required for access, for entry into buildings, and is shown to the armed Security Police when entering the NIST Gaithersburg campus.

Identification Badges: Contractor employees shall comply with NIST identification and access requirements. The Contractor employee is responsible for absences due to expired identification and access documents. Each Contractor employee shall wear a visible identification badge issued by the NIST Security Office. The issued identification badge must show the Contractor employee’s full name, title, and if required by NIST, the words “Contractor”. The Contractor employee shall return the NIST identification badge and vehicle pass to the TPOC, or Contracting Officer (CO) upon termination of their services under this contract.

Contractor Registration: The contractor shall provide the name and citizenship information of the on-site technician(s) to the NIST TPOC prior to arrival at the NIST Gaithersburg campus. The TPOC will submit the name(s) and citizenship information to the NIST Office of Security in order for a given Contractor employee to enter the NIST Gaithersburg campus to perform on-site preventive maintenance or repairs of the instruments.

Vehicle Registration: All Contractor employees must register their vehicles with the NIST Security Office to gain access to the NIST Gaithersburg campus. A valid driver’s license, Government-furnished civilian ID, proof of vehicle insurance and current registration must be presented to the NIST Security Office, at which time a NIST vehicle pass will be issued. The NIST vehicle pass shall be displayed on the vehicle’s rear-view mirror in accordance with NIST Security Office’s instructions. The Contractor employee shall follow NIST procedures for removal and turn-in of the vehicle pass upon termination of their services under this contract.

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