515 72ND ST SE 2023 2026-01-06 - Laserfiche WebLink

3. Platforms shall be constructed of either interlocking 1.125"x 6"treads welded to side rails,or.5"-.125" standard expanded metal (EM)welded to a tubular support frame which connects the side rails. 4. Platforms shall be designed for variable height adjustment. 2.4 SUPPORT LEG ASSEMBLIES a. ENGINEERING 1. All support assemblies shall be designed to support the ramp and platform sections specified in sections 2.2 and 2.3. 2. Support assemblies shall be designed to hold the support tubes and legs vertical in all locations. 3. Support tubes and legs shall have a minimum wall thickness of.094". b. MATERIALS 1. Support assemblies shall be constructed of aluminum alloys 6005-T5 or 6061-T6 with polymer feet. 2. All fasteners shall be grade 5 strength or higher with zinc plated or zinc chromate finish. c. DESIGN 1. Support tubes and legs shall be adjustable for variations in height. 2. All aluminum brackets shall be supplied for attachment of the ramps and/or platforms to the proper support tube or leg. 3. All legs shall have a 7.375"x 7.375" (minimum)square polymer foot. 2.5 HANDRAILS a. MATERIALS 1. Handrails shall be all aluminum construction from alloys 6005-T5 OR 6061-T6. b. DESIGN AND FABRICATION 1. Handrails shall be provided along both sides of ramp segments.The inside handrail on turn platforms and dogleg ramps shall always be continuous.Gripping surfaces shall be continuous,without interruption by newel posts,other construction elements, or obstructions. 2. Handrails shall be 1.5" diameter. 3. The top of the handrail gripping surface shall be mounted between 30"and 36"above the ramp surface, and the top of the intermediate rail,when present,shall be mounted between 18"and 22"above the ramp surface. 4. All handrail tubes shall be deburred and all sharp edges removed from gripping surfaces. 5. All handrails shall be supplied with mill finish (optional powder coat finish available). 6. All platform handrails shall include a 1 .5"x 2"curb located 1 .5"to 2 .5"above the platform deck except the Vertical Picket Handrail. 2.6 VERTICAL AND HORIZONTAL PICKETS(OPTIONAL) a. MATERIALS 1. Pickets shall be all aluminum construction from alloys 6005-T5 OR 6061-T6. b. DESIGN AND FABRICATION 1. Pickets shall be provided along both sides of ramp segments and all sides of platforms except where ramps attach. 2. Pickets shall be spaced so no gap exceeds 4". 3. Pickets shall be provided with handrails which meet the same requirements as Section 2.5. 4. Pickets shall be either 1"square(vertical) or 1.5" diameter(horizontal). 5. Pickets shall be supplied with brushed,architectural finish or mill finish (optional powder coat finish available). PART 3 - EXECUTION 3.1 EXAMINATION a. Verify site conditions are conducive to proper assembly of product. 3.2 ASSEMBLY a. Install prefabricated aluminum ramps according to manufacturer's instructions and the approved drawings without damage to components,shape,or finish.Repair or replace any damaged components. b. Align and maintain uniform slope and horizontal joints as installation progresses. c. Fasten components in place as indicated in shop drawings or plans. d. Install railings and pickets according to manufacturer's instructions and as shown on approved drawings. 3.3 MAINTENANCE a. System must be maintained in accordance with manufacturer's instructions. 3.4 IMPORTANT NOTE a. Specifications are subject to change without notice.