Case Study - Shoreham Chimney



Zenith has successfully completed a major refurbishment project on the 100m high steel chimney for VPI at their Shoreham Gas-Fired Power Station in West Sussex, United Kingdom. Our in-house team of engineers oversaw the inspection and full structural assessment of the chimney to determine its structural integrity following over 20 years of operation. A detailed laser scan survey was conducted to identify areas of deformity which were then analysed using finite element analysis to assess the impact on overall structural integrity. The assessment detailed the requirement for structural strengthening at a number of locations. Initially, Zenith was contracted to refurbish the upper 60m of the chimney which included removing and reapplying the coating system and replacing the permanent access ladders and platforms. We designed and installed a twin-deck full circumferential suspended access platform to facilitate access throughout the full height of the upper works. The platform design allowed for rapid movement, limiting the duration of the project, saving both outage time and reducing costs. The platform also allowed for VPI engineers to gain access to the work areas. Zenith removed, redesigned and replaced all of the existing ladders, rest platforms and circumferential platforms, reducing ladder lengths and increasing handrail heights to ensure compliance with current industry regulations. The replacement of the permanent access was undertaken via the use of the suspended platform and suspended access cradles. The twin-deck access platform was completely encapsulated to enable grit blasting and painting of the external chimney shell. The platform contained all grit and debris from the blasting and painting works, ensuring environmental compliance throughout the project whilst working at height. The enclosed work area ensured a high quality of paint finish was achieved and to provide a long term coating which is located in an aggressive costal environment. In addition to the coating and access works, all flange bolts were replaced.

The design assessment indicated that repair and modification of the tuned mass damper was required. A new damping system was designed and specified to Zenith engineering requirements. The damper components were then replaced working around client shutdown windows.


Steel chimney refurbishment





Telephone +44 (0)131 440 3000



Following the successful completion of the upper works, Zenith was re-appointed to undertake refurbishment of the lower 40m of the chimney. The works consisted of installing the required strengthening works, removing the existing cladding and coating systems followed by the reapplication of a new high temperature coating, 100mm thick insulation and aluzinc cladding. Access for the works was provided via traditional scaffolding internally and externally. All internal works were carried out under Zenith’s confined space procedures. The strengthening works, including the installation of new steelwork and overplating, were undertaken in accordance with BS EN 1090 Execution class 3.

Zenith has an unrivalled reputation in designing, fabricating and installing safe, innovative bespoke access systems on tall and awkward structures throughout industry. Our dedicated team of structural engineers lead the field and have developed a global reputation for excellence. Also, having the ability to perform a comprehensive range of repair strategies and techniques in-house, Zenith is able to provide a service encompassing the initial concept design completely through to eventual project execution.

Page 1 Page 2

Made with FlippingBook Annual report maker