SECTION ABOVE-GROUND FIRE PROTECTION WATER STORAGE TANK

Transcription

1 SECTION ABOVE-GROUND FIRE PROTECTION WATER STORAGE TANK PART 1 - GENERAL 1.1 DESCRIPTION A. This specification covers the furnishing of all labor, material, equipment, tools, services and erection of three 5,000 gallon (nominal), Factory Powder Coated Bolted Steel fire water storage tanks, as manufactured by Superior Tank Co., Inc., Rancho Cucamonga, CA, United Industries Group, Newport Beach, CA, Central Valley Tank, Fresno CA or an approved equal, and as shown on the plans and specified herein. B. The bolted steel tank shall conform to the requirements of AWWA D and NFPA 22 - Standards for Water Tanks for Private Fire Protection, Current Edition. 1.2 DESIGN CRITERIA A. Design loads: The reservoir structure shall be designed in accordance with the following: 1. Minimum capacity 5,000 gallons (nominal) 2. Inside diameter 10-foot +/- 3. Tank height 8.5-foot +/- 4. Seismic Design Parameters: a. Seismic Use Group II b. I E 1.25 c. Site Class (Soil) D d. S S 2.036g e. S g f. F a 1.00 g. F v Specific Gravity of contents Wind load 100 mph, Exposure Category B 7. Deck load 15 psf 8. Allowable Soil Bearing 1,000 psf, (assumed) 9. Design standard AWWA D and NFPA SUBMITTALS Civil

2 Section Page 2 A. As specified in Section B. Shop Drawings: Submit shop drawings of the bolted steel reservoir and all accessories for review and approval by the State prior to beginning any related shop fabrication or erection. Include sufficient data to show that the reservoir and accessories conform to the requirements to these Specifications. C. Submittals shall include: 1. Complete structural calculations, including forces that must be resisted by the foundation, maximum tension, compression and shear at each anchor bolt or embedded plate, maximum and allowable stresses for bolted steel shell, floor, and roof. The tank shall be designed using rational methods in accordance with accepted engineering practice. Calculations shall be stamped and signed by a civil or structural engineer currently registered in the State of California. 2. Detailed fabrication and erection drawings and details for the tank and all accessories. Include drawings for all shell, roof and floor penetrations and bolt holes for mounting accessories. 3. Submit tank manufacturer s erection manual. 4. Certified mill tests on steel plate and structural members demonstrating that the physical and chemical requirements of this Specification have been met. 5. Submit manufacturer s certificate of compliance with NSF Standard Submit product data and material safety data for sealant and repair materials to be used. 7. Submit foundation design. 8. Submit Seismic Anchor Design. 1.4 QUALIFICATIONS OF TANK MAUNFACTURER AND INSTALLER A. The manufacturer and installer shall have five years experience and be a specialist in the design, fabrication, and erection of factory powder coated bolted steel tanks and appurtenances. Tank erection shall be supervised by tank manufacturer trained personnel. B. Provide a list of at least five (5) tanks presently in fire protection water storage service designed to AWWA D or -97 and NFPA 22 standards, of equal or greater size, operating satisfactory for a minimum of five (5) years, including telephone number of Contracting Officer.

3 Section Page PRODUCT HANDLING A. Packaging: All plates, members and miscellaneous parts shall be packaged for shipment in such a fashion as to prevent abrasion, scratching or marring of the finished coating. Upon arrival at the job site, the shipment will be inspected by the State s Representative and any damaged parts will be rejected. B. Storage: Adequately support materials to prevent warpage and other damage. Do not store directly on the ground and protect from the weather. 1.6 CLOSEOUT, SUBMITTALS A. As specified in Section B. Submit material list and manufacturer s operation and maintenance data for field inspection and repair of coatings and all accessories. 1.7 WARRANTY A. The tank manufacturer shall warrant the tank against any defects in workmanship and materials for a period of one (1) year from the date of project acceptance. In the event any such defect should appear, it should be reported in writing to the manufacturer during the warranty period. PART 2 - GENERAL 2.1 TANK A. The Manufacturer shall furnish, erect and test the tank, as required by AWWA D and NFPA 22. The Manufacturer shall be completely responsible for the construction and satisfactory performance of the tank during the guarantee period. The tank shall conform to AWWA D and NFPA 22, to the latest edition California Building Code, and to the requirements of the plans and these Specifications. The supplier shall submit for approval complete and detailed plans for the tank and appurtenances. B. The Factory Powder Coated, bolted steel tank shall have a cone roof, sloped to drain toward the shell. Provide the reservoir complete with all pipe connections, access openings, nozzles, taps, drains, ladders, vent, and other accessories as shown on the plans or required herein. C. Tank shell sheets shall have mild strength per ASTM A607, Grade 30 and high strength per ASTM A607, Grade 50. Manufacture double bolt line such that holes are vertically staggered and no two holes are in line horizontally. All shell

4 Section Page 4 penetrations and bolt holes for mounting of accessories shall be factory fabricated after surface preparation and prior to cleaning. Contractor shall furnish one spare sheet of each size and type. If these sheets are not incorporated, they and any other rejected materials shall remain the property of the Contractor and must be removed from the site and the Park prior to final acceptance of the work. Sheet edges of sidewall and floor plates shall be mechanically rounded. 2.2 ROLLED STEEL STRUCTURAL SHAPES A. Material shall conform to AWWA D103-09, Section 2.5 and ASTM A36 or ASTM A992 and NFPA BOLT FASTENERS A. Bolts used in tank lap joints shall be ½ inch 13 UNC-2A tolled thread, and meet the minimum requirements of ANSI/AWWA D103-09, Section 2.2. and NFPA 22. B. Bolt Material: C. Surface Preparation: 1. SAE Grade 2: Tensile strength 74 ksi minimum; proof load 55 ksi minimum; allowable shear stress 18, 164 psi. 2. SAE Grade 5/ASTM A325 (1 ¼" bolt length): Tensile strength 120,000 psi min; proof load 85,000 psi min; allowable shear stress with threads excluded from the shear plane 29,454 psi min. 3. SAE Grade 8/ASTM A490 (> 1 ¼" bolt length): Tensile strength 150,000 psi min; proof load 120,000 psi min; allowable shear stress with threads excluded from the shear plane 36, 818 psi min. 4. ASTM A490-REV A-92: Tensile strength 150 ksi minimum; proof load 120 ksi minimum; allowable shear stress 36,818 psi. 5. Bolt Finish: Zinc Plate: inch minimum under bolt head; inch minimum on shank; inch on last five threads; irridite #3 bronze color coat. 6. Bolts shall include a minimum of four splines on the underside of the bolt head at the shank to resist rotation during torquing. Bolt lengths shall be sized as to achieve a neat and uniform appearance. Excessive threads extending beyond the nut after torquing will not be permitted.

5 Section Page 5 D. Bolt Head Encapsulation: High impact co-polymer encapsulation of entire bolt head up to shank; natural resin only, color ingredients to be added such that color shall appear same color as tank. E. Exterior exposed nut, washer and bolt thread cover, same color as tank. F. All lap joint bolts shall be properly selected such that threaded portions of the bolt will not be exposed to the "shear plane" between tank sheets. 2.4 SEALANTS A. Lap Joint Sealant: Shall be a one component polyurethane compound. The sealant shall cure to a rubber-like consistency having excellent adhesion to the glass coating, low shrinkage and a minimum life of 20 years when subject to exterior exposures. Sealant curing rate at 73 degrees F/50% relative humidity: tack free six to eight hours; final cure: days. The sealant shall be a one component, moisture cured, polyurethane compound. Neoprene gaskets and tape sealer shall not be used. B. Floor: Polyethylene copolymer caps and sealant shall be used to cover the bolts, nuts and washers exposed on the inside of the floor. 2.5 ROOF A. Tank roof shall be radially sectioned roof fabricated from powder-coated, bolted steel panels, as produced by tank manufacturer, and shall be assembled in a similar manner as the sidewall panels utilizing the same sealant and bolting techniques, so as to assure a weather/air tight assembly. The roof shall be clear-span and self-supporting. Both live and dead loads shall be carried by tank walls. The roof shall be of a rolled knuckle design with no rolled angle connection between sidewall and roof panels. B. Materials: All alloys shall be high quality marine grade aluminum. 1. Triangulated dome frame struts: AA6005A-T6 aluminum. 2. Structural frame node plates: 0.375" nominal thickness, AA6061-T6 aluminum. 3. Triangular dome panels: 0.050" nominal thickness, AA3003-H16 aluminum sheet. 4. Triangular skylight panels (if specified); nominal thickness of ¼" thick clear acrylic or polycarbonate. 5. Perimeter tension/compression ring: AA6005A-T6 aluminum.

6 Section Page 6 6. Fasteners: AA2024-T4 aluminum or austenitic series 300 stainless steel as required by the manufacturer's design. 7. Sealant: Silicone conforming to Federal Specification TT-S Gaskets: Silicone conforming to Federal Specification ZZ-R-765, Class 2, Grade 50 or equal or neoprene conforming to ASTM C Dormers, doors, and hatches: AA6061-T6, AA6005A-T6, AA5086-H34 or AA5052-H36 aluminum, 0.090" nominal thickness. C. Roof Access Hatch: Minimum opening size, 24 inch clear. Hatch shall be hinged and have a hasp for locking. Hasp shall be stainless steel. Frame shall have bolted connection to tank roof structure with water tight seal. 2.6 ROOF VENT A. A 12 inch minimum screened vent shall be provided on the roof. The vent shall be fabricated to provide removable screened openings between the vertical support members of the vent. The screened openings of the vent shall be sized by the manufacturer to all venting of a 300 gpm pumping rate. An effective area of 75% of screen opening shall be assumed. The screen shall consist of one layer of Type 316 stainless steel: 16 x 16 x wire mesh insect screen. B. The tank roof shall have a curbed, upward opening 24-inches square, minimum hatch located near the ladder. The curb shall extend at least 4 inches above the tank. The hatch cover shall be hinged and shall have locking provisions. The hatch cover lip shall extend for a distance of 2-inches down on the outside of the curb. 2.7 TANK ACCESSORIES A shell manhole: Provide a 24, minimum, hinged shell manhole located as shown on the drawings. The center of the manhole shall be located 30 inches above the bottom of the tank. B. 1 4 outlet nozzle. C. 1 4 inlet nozzle. D. 1 4 drain nozzle E. 1 4 overflow with downcomer steel internal and external overflow pipe and supports. Overflow pipe assembly shall be powder epoxy lined and coated.

7 Section Page 7 F. Ladder Provide a galvanized steel welded exterior ladder with backguard as shown on the plans. The ladder shall have a lockable closure at the bottom. G. Identification Plate: Manufacturer s nameplate shall list the tank serial number, tank diameter and height, and maximum design capacity. H. 1 liquid level indicator with gauge board. Superior Tank Model #2400, or equal, with Type 316 stainless steel internals and complete with float and target board assembly. 2.8 SPARE SHELL SHEETS A. Contractor shall furnish one spare shell sheet. Spare sheet shall be sized for the first chime or ring. If it is not incorporated in the construction, it and any rejected sheets shall remain the property of the Contractor and shall be removed from the park prior to final acceptance of the work. PART 3 - EXECUTION 3.1 TANK SITE EXCAVATION AND GRADING A. Per Section FOUNDATION A. Construct in accordance with manufacturer s recommendations. B. Prepare subgrade in accordance with the recommendations of Appendix A Geotechnical Investigation, and its addendums. 3.3 PROTECTIVE COATING A. General: All metal plates, supports, members and miscellaneous parts, except bolts, shall be Factory Powder Coated in accordance with AWWA D103, Section 10.6 and this Section. Field coating, other than touch-up, will not be permitted. B. Surface Preparation: 1. Prior to application of coating, all metal plate, supports, members and miscellaneous parts, other than fasteners shall be thoroughly cleaned by a hot-rinse wash process followed immediately by hot air drying.

8 Section Page 8 2. All steel surfaces shall be sandblasted to equivalent of a SP 6 commercial blast metal finish. The surface anchor pattern shall be no less than 1.5 mils. 3. All steel surfaces shall receive an iron phosphate coating applied with a power spray washer with not less than 25 psi pressure, followed by a warm water rinse and by an acidulated sealant. Then spray a final deionized water rinse to prevent rusting prior to the powder coating application. 4. All steel surfaces shall drip dry for seven (7) minutes prior to entering the dry off oven for eight (8) minutes at 425 degrees F. C. Coating: 1. All interior steel surfaces, support members and miscellaneous parts shall receive 5 mils minimum average dry film thickness using Dupont "Tank Tan (an NSF 61 approved, Thermal Set Epoxy Powder Coating). 2. All exterior steel surfaces, support members and miscellaneous parts shall receive 3 mils minimum average dry film thickness using Dupont Superior Sand (a Thermal Set TGlC-Polyester Powder Coating). 3. All exterior surfaces shall be colored Butler-Cote Sandalwood or similar. 3.4 CONSTRUCTION A. Field erection of Factory Powder Coated bolted steel tanks shall be in strict compliance with manufacturer's recommendations and performed by manufacturer s employees or certified erection crew to alleviate any potential disputes in coating quality or erection thereof. Particular care shall be exercised in handling and bolting of the tank plates, supports, and members to avoid abrasion or scratching the coating. Prior to placing water in the tank, a holiday inspection of the entire tank, corners included, will be provided and performed by the manufacturer in the presence of the State s Representative. Touch-up coating shall be done per the manufacturer's recommendations where needed and as directed. 3.5 CLEANING A. General: Cleaning shall not take place until sealant has fully cured. All inside surfaces below the high water level will be inspected by the State s Representative prior to chlorination and leakage testing; touch-up shall be done as directed.

9 Section Page 9 B. Cleaning: Remove all tools, rags and any other material not part of the structure or its accessories from the reservoir interior. Thoroughly clean interior surfaces or the shell floor and accessories of the reservoir using a highpressure water jet, sweeping, scrubbing or other equally effective means. Discharge or otherwise remove all water, dirt and foreign material, accumulated in the cleaning operation from the tank. Dispose as directed by State s Representative 3.6 LEAKAGE TESTING A. Retention of the chlorine solution for a 24-hour period during disinfection will also constitute the tank leakage test. Repair any leaks disclosed in the test, and repeat the required test for leakage. After the holding period, purge all highly chlorinated water from the drain piping. Subject to satisfactory bacteriological sampling and testing, acceptable aesthetic quality, and adjustment of free chlorine residual to a concentration of not more than two parts per million (2 mg/l), the tank may be put into service. 3.7 ANNIVERSARY INSPECTION A. On or before the one year anniversary date of final acceptance of the tanks, the Contractor shall arrange for the manufacturer s factory trained representative to make a visual inspection of the reservoir interior coatings and accessories, and the immediate area surrounding the reservoirs and shall notify the State s Representative at least ten working days prior to the scheduled date of the inspection. The State s Representative will be present during the inspection. A written summary of this inspection shall be filed with the State s Representative. END OF SECTION