Buried Steel Bridge: High Speed Railway Ecological Overpass

Article provided by the National Corrugated Steel Pipe Association

This amazing project is the first ever corrugated steel plate ecological overpass constructed on a high speed railway in the world!

After an initiative backed by ViaCon Turkey, this corrugated steel bridge structure, dubbed “Ecological Bridge Structure” by Turkish State Directorate of Railways, was built and implemented in Mihalıçcık/Eskişehir. This amazing steel structure was introduced for the sole purpose of helping the nearby wildlife.

After the completion of the reinforced concrete foundation, the CSP structure was completed within an astonishing 22 days.

Before construction of the bridge started, it was estimated that it would take close to a year upon completion before the local wildlife would start to use bridge. Amazingly, the wild animal population was photographed using the bridge only 1 month after it was built!

A deep corrugated steel plate structure was chosen due to the location in which the crossing was to be built and the dimensions that would be easily achieved using steel. The structure, which has a span of 18.41 meters and a height of 9.56 meters, was designed to provide a crossing over a 2-track railway crossing with a length of 74.15 meters.

After the completion of the reinforced concrete foundation, the CSP structure was completed within an astonishing 22 days. With the completion of the backfill layers after the assembly of the steel structure, the corrugated steel Ecological bridge structure was finalized and put into use.

All parts of the corrugated steel structure were produced in Sakarya/Turkey. A total of 229 tons of steel were used in the assembled of the structure.

Technical Specs: HL93 Live Load
Cover Depth: 2 m
Backfilling: Aggregate compacted to 95% standard proctor density(γ = 19,5 kN/m3)
Durability: 75 years
Corrosion Protect: Zinc coating of thickness conforming EN ISO 1461 standard

View Original Article

What are buried steel bridges?

Buried steel bridges provide an economical choices for bridge replacement or bridge rehabilitation.

They essentially are a corrugated steel pipe or structural plate pipe systems that is “buried” with backfill to carry loads through soil-structure interaction. This means the bridge structure itself and the backfill soils surrounding the structure interact with each other to support the loads. In effect, the backfill material is part of the bridge.

Because of this interaction, the bridge structure is typically lighter, and there can be significant savings in structure costs.

There are also many cases where buried bridges can carry heavier loads than traditional bridges because of the benefits of spreading vehicle loads through the fill. Buried bridges do not require abutments; and unless foundation soil conditions are poor, do not typically
require deep foundations.

An additional benefit with buried bridges is that they can be tailored to site conditions and geometric requirements. The design includes inputs for site soils and backfill, meaning that locally available materials can often be used in construction and the structure can be tailored to fit the needs of the site and the owner’s requirements.

Learn more about buried steel bridges→

Related Resources: Buried Bridges

Buried Steel Bridge Riverside Iowa Lane Enterprises

Buried Bridge

Buried Steel Bridge Preserves Streambed While Supporting Heavy Loads

A new galvanized buried steel bridge in Riverside, Iowa, supplied by SSSBA member Lane Enterprises, replaced a weight-restricted structure and restored direct access for local farmers. Its open-bottom steel design preserves the natural streambed, enhances durability, and provides a cost-effective solution for rural infrastructure.