Civil Engineering March 2021 | Vol 29 No 2

The welded compound anchor plate op- tions were designed for quantified service category F71 in accordance with BS EN 1993-1-9 for fatigue loading with the utili- sation factor taken as > 0.5. Fabrication was specified as EXC4 category in accordance with BS EN 1090-2, requiring fully certi- fied production records of every weld and associated fabrication treatment process. During the procurement process local and international suppliers were ap- proached for the original cast steel solution and the revised compound welded steel plate option. The compound welded steel plate option was the preferred solution, since it offered the best pricing, shortest lead time, and conformed to quality requirements. The successful tenderer for this work was Allweld Marine & Industrial, who manufactured the new anchor plates in a record time to successfully mitigate delays to the contract. PROJECT FINALISATION Construction of the New Ashton Arch Bridge is currently well underway, with the arch superstructure (in its temporary position) completed in August 2020, and completion of the overall project sched- uled towards the second half of 2021. The new bridge is currently located in a temporary position adjacent to the existing bridge. Here it serves as a temporary bypass while the demolition of the original bridge and the construction of the new permanent abutments takes place. Following this, the new tied-arch bridge will be jacked transversely into its final position over the space of a weekend during the second half of 2021, after which approaches as well as the remainder of the project will be completed. On completion, a total of 18% of the contract value will have been allocated to the creation of economic opportuni- ties and entrepreneurial capacity in the surrounding areas. This includes a local labour utilisation of 65 000 person days and 300 work opportunities which were created for exempted micro enterprises and qualifying small enterprises. CONCLUSION The successful completion of the New Ashton Arch, to modern design standards, can be attributed to the dedication and excellent teamwork of all the participants. The design of the new arch bridge required careful attention to ensure that the final structure behaves as envisaged by the designer. The construction process also entailed technically complex chal- lenges which were resolved timeously, so that delays to construction were mini- mised. Local manufacturers, with support from overseas specialists, were used to manufacture specialised components such as arch stay anchor plates and bearings. The result is a unique application of this bridge engineering technique for a concrete tied arch bridge in South Africa.  REFERENCES Ronné, P, Newmark, A, du Toit, N & van Wijk, H, 2018. New Ashton Arch – functional assessment of direct and indirect construction costs and evaluation of service life with respect to flooding risk. Proceedings of the fifth International Conference on Concrete Repair, Rehabilitation and Retrofitting, Cape Town, South Africa. Edited by Mark G.Alexander, Hans Beushausen, Frank Dehn, and Pilate Moyo, DOI: https:// doi.org/10.1051/matecconf/201819906003 . van Wijk, H, 2019. Validation of the deck behaviour due to post-tension loading of Ashton Arch Bridge. Cape Town: University of Cape Town. Figure 14 New Ashton Arch Civil Engineering March 2021 17 Figure 13 Manufacture and installation of final anchor plates