Design and Construction of Permanent Sheet and Pipe Pile Basement Walls with the Press-in Piling Method-Paper

Paper

Pdf Summary

The paper describes the design and construction of permanent steel sheet-pile and pipe-pile basement walls using the press-in piling method at the St. David’s 2 mixed-use redevelopment in Cardiff, UK. The two-level underground parking structure measured approximately 290 by 100 metres. Its steel walls served first as excavation support and then as permanent structural elements carrying both horizontal and vertical loads.<br /><br />Steel pile walls were selected over secant pile walls to reduce construction time and cost, while avoiding the additional traffic, noise, and dust associated with concrete delivery. Press-in equipment installed the piles hydraulically, with minimal noise and practically no vibration—important in the busy city-centre setting. Auger attachments enabled installation through very hard mudstone and siltstone, where measured SPT values reached 500. The method also allowed precise pile placement and real-time monitoring of installation forces.<br /><br />Before production piling, test piles and static load tests were used to establish required net toe-resistance thresholds: 230 kN for sheet piles and 650 kN for pipe piles. During construction, press-in force monitoring verified the capacity of every pile. Average measured net toe resistance at refusal exceeded the required values, reaching 283 kN for sheet piles and 1,041 kN for pipe piles.<br /><br />To control groundwater seepage, the project combined welded interlocks, water-stop plates, hydrophilic materials, and secure slab connections. The completed walls were incorporated into the basement and finished as exposed interior surfaces.<br /><br />The case study demonstrates that press-installed steel pile walls can provide an economical, space-efficient alternative to conventional basement-wall systems, while combining temporary shoring and permanent structural functions. Real-time capacity checks and reduced noise, vibration, and construction disruption were key advantages.

Keywords

press-in piling

steel sheet-pile walls

pipe-pile basement walls

mixed-use redevelopment

Cardiff UK

basement excavation support

permanent structural walls

static load testing

groundwater seepage control

low-noise installation