Red bridge investigation. Anu Ileperuma, Hastings DC and Natalia Uran, WSP

Red Bridge is located on Waimarama Road, Hastings, spanning across the Tukituki River, on a strategically significant, proposed High Productivity Motor Vehicle (HPMV) route in the district. Following inspection findings, where cracks were observed in parts of the bridge, and after an update of the VDAM General Mass regulations to 45/46 tonnes in December 2017, the bridge was restricted to 90% Class 1 with a 10km/hr speed restriction.  Along with Red Bridge, a further 25 bridges were also restricted within the district.
This presentation outlines a case study of how modern optimisation techniques have allowed Red Bridge, to support increased loading without the need for costly strengthening or replacement.  Optimisation has involved a wide range of conventional and state-of-the-art techniques, including materials testing, advanced modelling calibrated with field testing, and real time monitoring.  By refining both the capacity of the structure and the load demand, a significant increase in the bridges theoretical capacity was achieved, saving the asset owner over $2.6M in strengthening costs.

Anu is a Hastings District Council Bridge Engineer with a Bachelor in Civil Engineering (Hons).  Her portfolio covers the capital works and maintenance of bridge assets within the Hastings district and she has been with the Council for over five years.

Natalia is a Senior Bridge Asset Engineer with a Bachelor (Hons) in Civil Engineering and a Masters in Structural Engineering (Distinction).  Natalia has over 12 years’ work experience in the UK and New Zealand.  Natalia’s work experience has primarily been concentrated in bridge inspection, strengthening designs, live load bridge assessments and asset management for a wide range of clients including NZ Transport Agency and Local Authorities.  Natalia currently leads the Bridge and Civil Structures team for the WSP Napier office.