Shield tunneling
Port and
harbor technology
Urban rejuvenation
/green technology

Civil Engineering Business: Reinforce and Repair by Compound Closingwall (RECC) Construction Method

The shuttering method using walls that can be reused for reinforcement and repair of underwater bridge piers.


Outline of the
construction method

The reinforce and repair by the compound closing wall construction method (RECC construction method) is a makeshift construction method in which the underwater part of the bridge is temporarily shuttered by a shuttering wall consisting of the lower box and the upper water stop plate in order to dry the inside of wall for safe and high quality reinforcement and repair of bridge piers. RECC construction method: (Reinforce and Repair by Compound Closing Wall) With this construction method, small units of multiple boxes are connected to one another and seated onto the bridge pier footing, and the water stop plate is installed above them, therefore, preliminary shuttering work is feasible even in narrow space and extremely low water area, where it is difficult to perform work using the conventional box shuttering construction methods. Also, materials can be easily used, meaning it is an economically efficient method. Patent: No. 5053339


Characteristics of the
construction method

High water stop performance

With the cushioning seal material and grout material filled for the lower box, secure water stoppage can be performed in a short period. For the upper stop plate, high water stoppage performance can be ensured by a liner and water stop packing. Since the composite wall retains the dry state with high water stop performance, safe and high-quality reinforcement and repair work can be performed.

Work at low limited heights and in a low water area is also feasible

The lower box is a floating structure with low draft and freeboard, it is not affected by the space under the beam or the water depth. The lower box and upper water stop plate do not require a large-sized crane for installation and removal.

Applicable to any kinds of bridge piers

The composite wall consists of multiple precast materials, and by changing the combination, it can be applied to any type of bridge pier. The composite wall can be used for any bridge piers regardless of their shape by changing its shape.

Capable of shortening the process

Since the shuttering material of composite wall is manufactured in a factory, it is possible to shorten the shuttering process on-site. Since the composite wall consists of precast materials, installation, and removal are easy, and it can shorten the shuttering process on site.

High economic efficiency

Since the composite wall consists of precast materials, it can be easily used again and is economical.