Bent Cap Formwork

Construction Sequence of the Cap Beam

Construction site layout: Hoisting site replacement treatment → steel cap beam material entry → steel cap beam support system construction → steel cap beam and steel column installation → cap beam bottom plate laying → bottom plate elevation control and pre-arch setting → splicing connection between bottom plate and column → side Plate installation (connected to the column with splicing plate) and welding → stiffening plate installation and welding → top plate installation and welding → non-destructive testing → anti-rust paint painting

Cover Beam Welding Sequence

Assemble and weld the column on site → lay the bottom side steel plate → use splicing plates to connect the steel cover beam bottom plate to the two side column plates respectively → weld the two steel plates of the bottom side plate → weld the bottom plate stiffened plate → block symmetrical lifting and welding Side panels and vertical stiffened panels, and at the same time use splicing panels to connect the side panels of the steel cover beam with the side panels of the column → Weld all side panels and vertical stiffened panels → Weld the transverse stiffened panels of the top panel to the top panel → Hoisting machine Weld the connection seam of the top plate and the side plate and simultaneously connect the top plate stiffened plate firmly → remove the temporary buttress

There are three types of roof girder structures in bridge engineering. Therefore, steel formwork is used in the construction of girder cover. The cover beam supports the use of cuplock scaffolding. Concrete pouring uses pumped concrete.

The construction process of cap beam: foundation treatment of supporting system → erection of supporting system → laying of cap beam bottom form → pile top concrete chiseling and cleaning → binding cap beam reinforcement → supporting cap beam side form and reinforcement → cap beam template pre-inspection and reinforcement Hidden inspection → pouring of cap beam concrete → demolding → curing

Support System Design

1. The foundation treatment is paved with 25-30 cm of 12% lime soil and compacted by a heavy-duty vibratory roller to ensure the bearing capacity of the foundation. The current ground should be lower than the foundation, and ensure unblocked drainage to prevent the foundation from being soaked. Before scaffolding is erected, a 5 cm thick scaffolding board is laid on the top surface of the flat lime soil according to the spacing of the vertical poles, and then the scaffolding members are assembled.

2. The main keel uses 10×15 cm square wood, which is arranged along the transverse bridge direction. The main keel is aligned with the centerline of the vertical pole, and the joint with the top support is wedge tightly. The secondary keel uses 10×10 cm square wood. The spacing is 25 cm, and the structural load part is encrypted to 10 cm. Uniform dimensions before the second keel shop.

3. The cross-bridge distance between the two piers and the scaffolding is determined to be 60cm. The distance between longitudinal bridges is 60cm, and the step distance of horizontal crossbars is 60cm; the outer part of the pier column cover beam scaffolding determines the distance between uprights is 90 cm, the distance between longitudinal bridges is 60cm and the step distance of horizontal crossbars is 60cm. The scaffolding is erected with a single row of two-way scissor braces, and every three rows of vertical poles are provided with a row of longitudinal scissor braces. The horizontal cross-bar scissor braces are evenly arranged in the height direction. The bottom of the steel pipe is 5cm, the thick wooden board, the adjustable base 30cm, and the top Hold 60cm. The poles mainly use 3m, 1.8m, 0.9m long steel pipes. Set a horizontal bar 20cm away from the base. The façade is equipped with double-row two-way scissor braces every 5 rows of vertical poles, which are continuously installed in the height and length of the entire facade. The scissor braces are connected with the vertical poles with fasteners. The lap length of the scissor braces is 100cm and uses 3 rotating buckles. The parts are fixed, and the distance between two adjacent joints is not less than 50cm.