W. Va. Code R. § 36-23-37

Current through Register Vol. XLI, No. 24, June 14, 2024

Section 36-23-37 - Concrete, Concrete forms, and Shoring

37.1. General provisions.

(a) General. -- All equipment and materials used in concrete construction and masonry work shall meet the applicable re­quirements for design, construction, inspec­tion, testing, maintenance and operations, as prescribed in ANSI A10.9-1970, safety re­quirements for concrete construction and masonry work.

(b) Reinforcing steel.

(1) Employees working more than six (6) feet above any adjacent working surfaces, placing and tying reinforcing steel in walls, piers, columns, etc., shall be provided with a safetybelt, or equivalent device.

(2) Employees shall not be per­mitted to work above vertically protruding reinforcing steel unless it has been protected to eliminate the hazard of impalement.

(3) Guying: Reinforcing steel for walls, piers, columns, and similar vertical structures shall be guyed and supported to prevent collapse.

(4) Wiremesh rolls: Wire mesh rolls shall be secured at each end to prevent dangerous recoiling action.

(c) Bulk concrete handling. Bulk storage bins, containers, or silos shall have conical or tapered bottoms with mechanical or pneumatic means of starting the flow of mate­rial.

(d) Concrete placement.

(1) Concrete mixers. Concrete mixers equipped with one (1) yard or larger loading skips shall be equipped with a me­chanical device to clear the skip of material.

(2) Guardrails. Mixers of one (1) year capacity or greater shall be equipped with protective guardrails installed on each side of the skip.

(3) Bull floats. Handles on bull floats, used where they may contact energized electrical conductors, shall be constructed of nonconductive material, or insulated with nonconductive sheath whose electrical and mechancial characteristics provide the equiva­lent protection of a handle constructed of nonconductive material.

(4) Powered concrete trowels. Powered and rotating-type concrete troweling machines that are manually guided shall be equipped with a control switch that will auto­matically shut off the power whenever the operator removes his hands from the equip­ment handles.

(5) Concrete buggies. Handles of buggies shall not extend beyond the wheels on either side of the buggy. Installation of knuckle guards on buggy handles is recom­mended.

(6) Pumpcrete systems. Pump­crete or similar systems using discharge pipes shall be provided with pipe supports designed for one hundred (100) percent overload. compressed air hose in such systems shall be provided with positive fail safe joint connec­tors to prevent separation of sections when pressurized.

(7) Concrete buckets.

(i) Concrete buckets equipped with hydraulic or pneumatically operated gates shall have positive safety latches or similar safety devices installed to prevent aggregate and loose material from accumulat­ing on the top and sides of the bucket.

(ii) Riding of concrete buckets for any purpose shall be prohibited, and vibrator crews and all other persons shall be kept out from under concrete buckets suspended from cranes or cableways.

(8) When discharging on a slope, the wheels of a ready-mix trucks shall be blocked and the brakes set to prevent move­ment.

(9) Nozzlement applying a ce­ment, sand, and water mixture through a pneumatic hose shall be required to wear protective head and face equipment.

(e) Vertical shoring.

(1) General requirements.

(i) When temporary storage of reinforcing roads, material, or equipment on top of formwork becomes necessary, these areas shall be strengthened to meet the intend­ed loads.

(ii) the sills or shoring shall be sound, rigid, and capable of carrying the maximum intended load.

(iii) All shoring equipment shall be inspected prior to erection to deter­mine that it is as specified in the shoring layout. Any equipment found to be damaged shall not be used for shoring.

(iv) Erected shoring equip­ment shall be inspected immediately prior to, during, and immediately after the placement of concrete. Any shoring equipment that is found to be damaged or weakened shall be immediately reinforced or reshored.

(v) Reshoring shall be pro­vided when necessary to safely support slabs and beams after stripping, or where such members are subjected to super-imposed loads due to construction work done.

(2) Tubular welded frame shor­ing.

(i) Metal tubular frames used for shoring shall not be loaded beyond the safe working load recommended by the manu­facturer.

(ii) All locking devices on frames and braces shall be in good working order; coupling pins shall align the frame or panel legs; pivoted cross bracers shall have their center pivot in place; and all components shall be in a condition similar to that of origi­nal manufacturer.

(iii) When checking the erected shoring frames with the shoring layout, the spacing between towers and cross brace spacing shall not exceed that shown on the layout, and all locking devices shall be in the closed position.

(iv) Devices for attaching the external lateral stability bracing shall be securely fastened to the legs of the shoring frames.

(v) All baseplates, shore heads, extension devices, or adjustment screws shall be in firm contact with the footing sill and the form.

37.2. Forms and shoring.

(a) General provisions.

(1) Formwork and shoring shall be designed, erected, supported, braced, and maintained so that it will safely support all vertical and lateral loads that may be imposed upon it during placement of concrete

(2) Drawings or plans showing the jack layout, formwork, shoring, working decks, and scaffolding, shall be available at the jobsite.

(3) Stripped forms and shoring shall be removed and stockpiled promptly after stripping, in all areas in which persons are required to work or pass. Protruding nails, wire ties, and other form accessories not nec­essary to subsequent work shall be pulled, cut, or other means taken to eliminate the hazard.

(4) Imposition of any construc­tion loads on the partially completed structure shall not be permitted unless such loading has been considered in the design and approved by the engineer­-architect.

(b) Vertical slip forms.

(1) The steel rods or pipe on which the jacks climb or by which the forms are lifted shall be specifically designed for the purpose. Such rods shall be adequately braced where not encased in concrete.

(2) Jacks and vertical supports shall be positioned in such a manner that the vertical loads are distributed equally and do not exceed the capacity of the jacks.

(3) The jacks or other lifting devices shall be provided with mechanical dogs or other automatic holding devices to provide protection in case of failure of the power supply or the lifting mechanism.

(4) Lifting shall proceed steadily and uniformly and shall not exceed the prede­termined safe rate of lift.

(5) Lateral and diagonal bracing of the forms shall be provided to prevent excessive distortion of the structure during the jacking operation.

(6) During jacking operations, the form structure shall be maintained in line and plumb.

(7) All vertical lift forms shall be provided with scaffolding or work platforms completely encircling the area of placement.

(c) Tube and coupler shoring.

(1) Couplers (clamps) shall not be used if they are deformed, broken, or have defective or missing threads on bolts, or other defects.

(2) The material used for the couplers (clamps) shall be of a structural type such as drop-forged steel, malleable iron, or structural grade aluminum. Gray cast iron shall not be used.

(3) When checking the erected shoring towers with the shoring layout, the spacing between posts shall not exceed that shown on the layout, and all interlocking of tubular members and tightness of couples shall be checked.

(4) All baseplates, shore heads, extension devices, or adjustment screws shall be in firm contact with the footing sill and the formmaterial and shall be snug against the posts.

(d) Single post shores.

(1) For stability, single post shores shall be horizontal­ly braced in both the longitudinal and transverse directions, and diagonal bracing shall also be installed. Such bracing shall be installed as the shores are being erected.

(2) All baseplates or shore heads of single post shores shall be in firm contact with the footing sill and the form materials.

(3) Whenever single post shores are used in more than one (1) tier, the layout shall be designed and inspected by structural engineer.

(4) When formwork is at an angle, or sloping, or when the surfaces shored is sloping, the shoring shall be designed for such loading.

(5) Adjustment of single post shores to raise formwork shall not be made after concrete is in place.

(6) Fabricated single post shores shall not be used if heavily rusted, bent, dent­ed, rewelded, or having broken weldments or other defects. If they contain timber, they shall not be used if the timber is split, cut, has sections removed, is rotted, or otherwise struc­turally damaged.

(7) All timber and adjusting devices to be used for adjustable timber single post shores shall be inspected before erection.

(8) Timber shall not be used if it is split, cut, has sections removed, is rotted, or is otherwise structurally damaged.

(9) Adjusting devices shall not be used if heavily rusted, bent, dented, rewelded, or having broken weldments or other defects.

(10) All nails used to secure bracing or adjustable timber single post shores shall be driven home and the point of the nail bent over if possible.

37.3. Definitions applicable to this sub­section.

(a) "Bull Float" A tool used to spread out and smooth the concrete.

(b) "Formwork" or Falsework" The total system of support for freshly placed concrete, including the mold sheathing which contacts the concrete as well as all supporting members, hardware, and necessary bracing.

(c) "Guy" A line that steadies a high piece or structure by pulling against an off-­center load.

(d) "Shore" A supporting member that resists a compressive force imposed by a load.

(e) "Vertical Slip Forms" forms which are jacked vertically and continuously during placing of the concrete.

W. Va. Code R. § 36-23-37