Ardill Payne & Partners (APP) was engaged by Woollam Constructions to undertake structural design and documentation for the pool upgrades at Ballina and Alstonville. Works for Ballina involved demolition of existing amenities building and pool, construction of new amenities building, café, pump/filter, storage rooms, new heats 25m Learn to Swim pool, 8 lane FINA compliant 50m pool, covered roof for 25m Learn to Swim pool, pool concourses and landscaped areas. Works for Alstonville involved construction of club house, pump/filter, storage rooms, new heats 25m Learn to Swim pool, 8 lane FINA compliant 50m pool, covered roof for 25m Learn to Swim pool and pool concourses and landscaped areas.
The key challenges were that the new pools incorporate a wet edge design to maintain the water level just below the surrounding concourse level, this aspect of the pool designs weighed heavily on structures and concourse designs. The challenges were to control total and differential settlement to be within very tight tolerances, the concourse areas surrounding need to shed storm runoff away from the pool whilst maintaining compliant gradients, and to ensure minimal interaction between the building and the pools to prevent unintended damage to either structure.
The solutions involved detailed review of geotechnical information, investigation of various piling options to refine differential settlements, so that cost effective foundation solutions could be determined and performance criteria met. The new building and covered roofs were isolated from the pool structures where possible and designed to reduce loadings to the pool shells. Concourse slab design and construction was completed in a manner to allow for differential movements and shrinkage of the two elements.