Open-Cut Tunnel & Underpass
Solution
Open-Cut Tunnel
When the lane width of a corrugated steel plate tunnel is widened (when the total effective width exceeds 20 m), a double-layer structure is applied considering the rigidity limits of the corrugated steel plate structure and construction conditions. When construction is conducted during public use, some lanes must inevitably be controlled for vehicle traffic, and since a foundation must be installed on the central divider, there is a disadvantage that the width of the tunnel must be expanded to four lanes when connected to the existing lane.
A solution to this is to apply EXSCor® corrugated steel plates, enabling construction with two-span and single-span structures while maintaining the existing lanes.
EXSCor® Solution
The EXSCor® corrugated steel plate has the world's highest rigidity, with an 8-9% increase in material but more than three times the rigidity compared to the existing large-frame corrugated steel plate by increasing the width and depth of the corrugation. When the EXSCor corrugated steel plate is used, the rigidity can be secured only with the main plate (without reinforcing plate) for a span of 24 m, so there is no process such as assembling reinforcing corrugated steel plates (Rib Stiffener Plate) and pouring reinforcing concrete (En-Cased Concrete) for reinforcing rigidity, making construction easier and reducing construction costs.
If reinforcing plates are used in the super-frame, it can be applied up to a span of 40m, so it can cross the median strip of an 8-lane road with a single span without installing a foundation, making it possible to construct while maintaining the traffic flow of the existing road.
Advantages of applying corrugated steel plates(cut tunnels, passages, waterways)
As Korea, along with many other countries, has entered an aging society, the aging of construction workers has accelerated significantly. As of 2018 in Korea, six out of ten construction workers were aged 55 or older.
In civil engineering sites, among safety accidents occurring during reinforced concrete construction processes, there have been cases in which formwork collapsed during concrete pouring because it failed to withstand the casting pressure.
The design of shoring systems considering concrete casting pressure requires that the bearing capacity of the actual construction site meet the specified design requirements. However, in practice, it is often difficult to fully satisfy these conditions.
Recently, contractors have been required to redesign shoring systems prior to construction to ensure installation stability in accordance with site-specific conditions. Furthermore, in the event of a safety accident, contractors are held accountable for the incident.
Typical CSS Type
2001, Korea
Excellence in application to urban construction
It does not disrupt the flow of traffic, and during construction in urban areas, it resolves complaints about traffic congestion caused by material delivery and eliminates the need for detours. (Compared to other construction methods: 90% reduction in traffic volume compared to rebar, ready-mixed concrete, and precast vehicles)
DAEDOTech Co., Ltd @Copyright
Curved section & Skew applicability
When applying to curved sections, pre-fabricated "Pre-Fabricated Beam Elbows" are used and bolted on-site. This maintains the road alignment as much as possible, resulting in superior vehicle drivability and visibility compared to standard concrete structures. Skews at the entrance and exit are also pre-fabricated at the factory, ensuring rapid on-site bolt assembly. Furthermore, Daedo Tech has implemented BIM design techniques down to the smallest detail, eliminating errors during fabrication and on-site construction.
DAEDOTech@Copyright
Minimum corrugated steel plate combination
We developed a combination that can be applied to emergency construction and high-fill sections by configuring a cross-section that can be installed by combining 2 to 4 sheets of large-diameter (380 mm x 140 mm) corrugated steel plates. In addition, we calculated the maximum soil cover according to the backfill material (subbase material, subgrade soil) and the degree of compaction (85% to 90%). With 2 sheets of corrugated steel plates, a circular cross-section of 1.8 m to 3.0 m can be constructed, reducing the number of bolts by 36% compared to the existing standard corrugated steel plate combination, thereby securing assembly and construction periods, improved waterproofing performance, and economic efficiency.
CSS Assembly
For corrugated steel plates, if a foundation is present, the bearing capacity is confirmed as indicated on the design drawings (pile construction is required, if necessary). Footing concrete is poured, and foundation concrete is constructed over it. During foundation concrete construction, a base channel is installed, connecting the corrugated steel plate to the reinforcing bars. After the foundation concrete has cured, the corrugated steel plate and base channel are fastened with bolts and nuts.
Corrugated steel plates are assembled in the correct order by checking the BP0-00S indicated on the drawing and the markings on the inside and outside of the corrugated steel plates. If the end treatment is a concrete facing wall, the anchor bolts and the facing wall reinforcement are fastened to complete the concrete facing wall, and then backfill is performed using the compaction material and compaction rate specified in the specifications. Before backfilling, waterproof the bolts and the space between the corrugated steel plates with gaskets and waterproof caps as specified in the drawing. In the case of a bevel, the bevel area is finished with Ring-Concrete after the waterproofing and backfilling processes.
CSS_Headwall Type
CSS_Bevel Type
En-Cased Concrete Stiffener
Patents Registered
10-0512522, 10-0609125, 10-1829819, 10-0448015, 10-0622059, 10-0634019,10-0799979, 10-0837212, 10-0842029, 10-0875250, 10-0875251, 10-1599811, 10-1620515,
10-1629291, 10-1801053