Published by department of transportation

48-2.03D Removal

Falsework removal includes lowering the falsework, blowing sand from sand jacks, turning screws on screw jacks, and removing wedges.

Except for concrete above the deck, do not release falsework supporting any span of a:

1. Simple span bridge before 10 days after the last concrete has been placed

2. Continuous or rigid frame bridge before 10 days after the last concrete has been placed:

2.1. In that span

2.2. In adjacent portions of each adjoining span for a length equal to one-half of the span where falsework is to be released

3. Simple span, continuous, or rigid frame bridge until the supported concrete has attained a compressive strength of 2,600 psi or 80 percent of the specified strength, whichever is greater

Do not remove falsework supporting any span of a continuous or rigid frame bridge until all required prestressing is complete (1) in that span and (2) in adjacent portions of each adjoining span for a length equal to at least one half of the span where falsework is to be released.

Release falsework supporting spans of CIP girders, slab bridges, or culverts before constructing or installing railings or barriers on the spans unless authorized.

Remove falsework for arch bridges uniformly and gradually. Start at the crown and work toward the springing. Remove falsework for adjacent arch spans concurrently.

Do not release falsework that supports overhangs, deck slabs between girders, or girder stems that slope 45 degrees or more from vertical before 7 days after deck concrete has been placed.

You may release falsework supporting the sides of girder stems that slope less than 45 degrees from vertical before placing deck concrete if you install lateral supports. Lateral supports must be:

1. Designed to resist rotational forces on the girder stem, including forces due to concrete deck placement

2. Installed immediately after each form panel is removed

3. Installed before releasing supports for the adjacent form panel
Do not release falsework for bent caps supporting steel or PC concrete girders before 7 days after placing bent cap concrete. Do not erect girders onto bent caps until bent cap concrete has attained a compressive strength of 2,600 psi or 80 percent of the specified strength, whichever is greater.

Remove falsework for structural members subject to bending as specified for simple span bridges.

Do not release falsework for box culverts and other structures with decks lower than the roadway pavement and span lengths of 14 feet or less until the last placed concrete has attained a compressive strength of 1,600 psi. Curing of the concrete must not be interrupted. Falsework removal for other box culverts must comply with the specifications for the release of bridge falsework.

Do not release falsework for arch culverts sooner than 40 hours after concrete has been placed.

Remove falsework piling to at least 2 feet below the original ground or streambed. Remove falsework piling driven within ditch or channel excavation limits to at least 2 feet below the bottom and side slopes of the excavated areas.

Dispose of falsework materials and work debris.

Falsework removal system employing methods of holding falsework by winches, hydraulic jacks with prestressing steel, HS rods, or cranes must also be supported by an independent support system when the falsework removal system is not actively lowering the falsework at vehicular, pedestrian, or railroad traffic openings.

Bridge deck openings used to facilitate falsework removal activities must be formed and located away from the wheel path. The formed openings must be wedge shaped with a 5-inch maximum diameter at the top and a 3-inch maximum diameter at the bottom.

Anchor 10-inch-square aluminum or galvanized steel wire, 1/4-inch-mesh hardware cloth with a 0.025- inch minimum wire diameter firmly to the inside of the soffit openings. Construct a 1/2-inch drip groove to the outside of soffit openings.

Clean and roughen openings made in the bridge deck. Fill the deck openings with rapid setting concrete complying with section 60-3.02B(2).

48-2.03E Falsework Lighting

48-2.03E(1) General

Falsework lighting includes lighting to illuminate the pavement, portals, and pedestrian walkways at or under openings in the falsework required for traffic.

Falsework lighting components must comply with section 86.

Lighting for pedestrian walkway illumination must be installed at all pedestrian openings through or under the falsework.

Design falsework lighting so that required maintenance can be performed with a minimum of inconvenience to traffic. Closing of traffic lanes for routine maintenance is not allowed on roadways with posted speed limits greater than 25 mph.

Illuminate the following only during hours of darkness as provided in division 1, section 280, of the California Vehicle Code: (1) Falsework portals and (2) pavement under falsework with portals less than 150 feet apart. Photoelectric switches must be used to control falsework lighting systems. Pavement under falsework with portals 150 feet or more apart and all pedestrian openings through falsework must be illuminated 24 hours per day.

Lighting fixtures must be aimed to avoid glare to oncoming motorists.

Type NMC cable with no. 12 minimum conductors with ground wire must be used. Fasten cable to the supporting structure at sufficient intervals to adequately support the cable and within 12 inches from every box or fitting. Conductors within 8 feet of ground must be enclosed in a 1/2-inch or larger Type 1 conduit.

Each illumination system must be on a minimum of 1 separate branch circuit at each bridge location. Each branch circuit must be fused, not to exceed 20 A.

For falsework lighting, arrange with the service utility to complete service connections. You pay for energy, line extension, service, and service hookup costs.

48-2.03E(2) Pavement Illumination

Illumination of pavement at vehicular openings through falsework must comply with the following requirements:

1. Fixture must include R/FL commercial-type flood lamp holder with protective covers.

2. Fixture must be fully adjustable with brackets and locking screws and allow mounting directly to a standard metal junction box.

3. Lamp must be medium-base 120 V(ac), 120 W, minimum, PAR-38 quartz-halogen flood lamp.

4. A continuous row of fixture types required must be installed at locations and spacing specified. Fixtures must be installed beneath falsework structure with the end fixtures not further than 10 feet inside portal faces. Fixtures must be installed and energized immediately after the members supporting them have been erected.

5. Fixtures along the sides of the opening must be placed not more than 4 feet behind or 2 feet in front of the roadway face of the temporary railing. Mounting heights of fixtures must be between 12 and 16 feet above the roadway surface and must present an unobstructed light pattern on the pavement.

48-2.03E(3) Portal Illumination

Illumination of falsework portals must comply with the following requirements:

1. On each side of each entrance portal, plywood sheet clearance guides must:

1.1. Be 4 feet wide by 8 feet high.

1.2. Be fastened vertically, facing traffic, with the bottom of the panel 3 to 4 feet above the roadway.

1.3. Have the center of the panel located approximately 3 feet horizontally behind the roadway face of the railing.

1.4. Have freshly painted panels for each installation with not less than 2 applications of flat white paint. Paint testing will not be required.

2. If ordered, repaint the designated areas to improve the general appearance of the painted surfaces. Repainting is change order work.

3. Falsework portals must be illuminated on the side facing traffic with 150 W, minimum, PAR floodlamps mounted on the structure directly over each vertical support adjacent to the traveled way, as needed to uniformly illuminate the exterior falsework beam, the clearance guides, and the overhead clearance sign. Each lamp must be supported approximately 16 feet above the pavement and approximately 6 feet in front of the portal face.

4. Portal lighting and clearance guides must be installed on the day the vertical members are erected.

48-2.03E(4) Pedestrian Walkway Illumination

Illumination of pedestrian openings through or under the falsework must comply with the following requirements:

1. Fixtures must be flush mounted in the overhead protection shield and equipped with a damage-resistant, clear, polycarbonate diffuser lens. Lamps must be standard incandescent 100 W, 120 V(ac).

2. Fixtures must be centered over the passageway at intervals of not more than 15 feet with the end fixtures not more than 7 feet inside the end of the pedestrian openings.

3. Pedestrian passageway light systems must be installed immediately after the overhead protection shield is erected.

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