FRP components arrive on site as finished parts — grating panels, pultruded beams, handrail sections, bolting kits. There is no welding, no concrete curing, no hot work. The field work consists of handling, cutting to fit where necessary, and mechanical assembly with fasteners. What follows is the distilled field practice from hundreds of industrial installations: the methods that reliably produce a dimensionally accurate, structurally sound FRP structure.
Handling and Storage
FRP grating panels and pultruded profiles are light enough to be handled by hand — a 1 m × 3 m molded grating panel weighs approximately 35 kg to 55 kg, and a 6 m pultruded I-beam weighs around 30 kg to 50 kg depending on the section. The light weight is an advantage, but it also invites mishandling: dragging grating panels across a concrete slab can abrade the surface grit and, on thin panels, can initiate delamination at the edge. Panels should be lifted, not dragged. For long pultruded sections, two-person lifts are adequate, but the lift points should be at the quarter-span positions to avoid excessive bending during handling.
Storage on site should be on level timbers or pallets, supported at intervals no greater than 1.5 m for grating panels and 2.0 m for structural sections. Stacking more than 10 panels high can crush the grit-top surface of the lowest panel. Pultruded sections stored outdoors should be covered with opaque sheeting to prevent the greenish surface discoloration that prolonged UV exposure can cause — though this is cosmetic and does not affect structural properties.
Cutting and Drilling
The glass fiber in FRP is abrasive. Standard steel saw blades will dull within a few cuts. The recommended tools are carbide-grit blades (for rough cuts where edge quality is secondary) and diamond-grit blades (for cuts that require a clean, splinter-free edge, such as grating panels that will be visible at the perimeter or handrail ends). For straight cuts on grating panels, a circular saw with a diamond blade is the most efficient tool. For notching and irregular shapes, a jigsaw with a carbide-grit blade works well, though the blades are consumable — expect to use one blade per 10 to 15 linear meters of cut in 38 mm thick grating.
Drilling holes in FRP for fastener installation should use high-speed steel or carbide-tipped twist drills, run at 1,500 to 3,000 RPM. A backing block of scrap timber under the workpiece will prevent breakout on the exit side of the hole. For holes larger than 12 mm diameter, a hole saw with carbide grit is preferred. All cut edges and drilled holes should be sealed with a light application of the manufacturer's touch-up resin if the component will be in continuous wet or chemical service — this seals the exposed glass fibers and prevents wicking.
Fixing: Clips and Bolting
FRP grating panels are secured to their support structure using mechanical clips — metal or FRP — that clamp the grating panel to the support beam. The clip spacing follows the manufacturer's recommendation and is typically one clip per support beam per panel width, with additional clips at panel ends and corners. For a 1 m wide panel on beams spaced at 1 m, this means a minimum of two clips per panel per beam. In areas subject to uplift (wind on open decks, vibrating equipment), clip spacing is reduced to 500 mm centers. The clip bolts, whether 316 stainless steel or FRP, are tightened to a torque that secures the panel without crushing it — for M10 bolts, a torque of 20 N·m to 25 N·m is typical. Over-tightening can crack the grating around the bolt hole; the visual indicator is the gel coat surface beginning to show radial cracks around the clip.
For structural connections — beam-to-beam, beam-to-column, bracing — bolted connections with FRP or 316 stainless steel bolts are standard. A typical bolted connection in an FRP frame uses an M16 bolt in a 18 mm clearance hole, with FRP flat washers under the bolt head and nut to distribute the bearing stress. The edge distance from the bolt hole center to the edge of the FRP member should be at least 2.5 times the bolt diameter in the direction of load, and 2.0 times the bolt diameter perpendicular to the load. These values are higher than for steel because FRP has lower bearing strength. All bolted connections in an FRP structure should be checked for slip-critical behavior if the connection will experience load reversal.
For the grating clips, bolting kits, and handrail fittings used in typical installations, see our Accessories & Hardware page.