Construction process of bridge seismic tie rods

The bridge's seismic bracing system incorporates various seismic measures, including anti-fall chains, longitudinal tie rods, dampers, rubber gaskets, seismic blocks, and bearings. Dampers are installed between the pier (abutment) cap and the main beam at the bridge expansion joints, and dampers are also installed on the piers and abutments at the expansion joints. Anti-fall chains are replaced by longitudinal blocks and longitudinal tie rods.

Construction Process of Seismic Tie Rods for Bridges

When constructing seismic tie rod retaining walls, masonry work and roadbed filling and compaction should be carried out simultaneously. When the concrete is laid to a height of 50cm above the corrugated metal pipe, it should be compacted first, then the trench should be excavated, the pipe buried, and then backfilled. After the corrugated pipe is buried, the following procedures should be carried out in sequence: anchor bolt installation, grouting, adding steel pads, tightening nuts, and sealing the anchor.

Tie-rod retaining walls are a new type of retaining structure formed using reinforced soil and anchor bolts. They consist of masonry, tie rods, and anchoring devices. The tie rods are horizontally anchored to both sides of the retaining wall and subjected to prestress. Their working mechanism is twofold: firstly, the tension of the tie rods balances the pressure of the backfill or the forces exerted on the retaining wall during construction by accidental loads such as earthquakes or car impacts, maintaining the wall's balance; secondly, when one side of the retaining wall tends to overturn or slide, the other side is passively protected by the tie rods; and thirdly, the prestress of the tie rods applies lateral pressure to the backfill, subjecting it to triaxial stress, significantly increasing its strength and contributing to overall stability and uniform settlement. Compared to gravity retaining walls, tie-rod retaining walls offer advantages such as lightweight structure, small masonry volume, good economic benefits, and excellent overall seismic performance, making them suitable for road shoulders and embankment sections with limited land area and high seismic fortification intensity.