PERI provided formwork for the escalator slab (from sub grade to bus station), the bus station columns and canopy slabs, and the substation roof.
In total, over 50 column forms were custom made in the PERI Bolton assembly facility; nearly all of the forms were single use due to the various pour heights and the column shapes and dimensions. 15 of the columns were ‘art columns’; these provide support for the bus canopy roof, and are the focal point of the project. Due to the density of the reinforcement and a central steel beam, all of the columns were poured using self-compacting concrete which was pumped from the base of the form using the PERI BPA Pump Connector. The art columns were poured in one pour from grade to underside of canopy roof and had very strict finish requirements; no ties were allowed in the pour, no pour joints were permitted, and the plywood had to be in a uniform pattern.
A fresh concrete design pressure of up to 160 kN/m² was used due to the self-compacting concrete. PERI’s Engineering department opted to use RCS Rails as horizontal walers to accommodate the high loads that resulted from such a high concrete pressure.
Due to the complexity and accuracy required, making the forms on site would have been very challenging. PERI’s assembly team played an important role in the success of the project; they ensured that the fabrication and assembly was of an extremely high standard. PERI also worked closely with the customer to ensure that each column form was assembled and delivered to site on time.
"We were extremely pleased with the professionalism of the PERI team, and the quality of workmanship applied to these columns. With these columns not only being exposed, but being considered Art Columns, we needed to ensure the utmost quality. Through the co-ordination of both parties, we were able to achieve our desired finishes using the pre-fabricated forms.”
RCS Rails, PERI BPA Pump Connector