Sub-industry
Public Buildings
Problems
Subsidence
Location
NSW
Year
2016
Solutions
Void Filling
Technology
Permeation Grouting
The problem
The Box Hill Motel, located in the eastern Melbourne suburb of Burwood, offers guests very comfortable three-and-a-half-star accommodation, including access to a large swimming pool.
In December 2016, the motel operator identified a problem with pool equipment and a leak in the skimmer box was identified. As repairs were being carried out, it was discovered that the suspended slab of the pool surround had cracked and dropped, resulting in an extreme hazard.
If the void had been left untreated, the cracked and uneven paving could have worsened. This may have resulted in significant and expensive damage to the pool area, as well as creating a safety and liability issue for the Box Hill Motel’s owners, Rata Pty Ltd.
Due to the void’s location, there was no access to its far end. Therefore, it required use of a thin, flowable material to fill it to ensure there were no residual air pockets once the material was in place.
Mainmark used a self-levelling cement grout to fill and seal the void in a single day. The placement was continuous, enabling Mainmark to fill the void quickly. The pool only needed to be closed for one day – a desirable result in the middle of a hot summer.
The solution
To safely fill the void under the poolside paving in a single day with minimal disruption to motel guests. The solution needed to be placed with access to the void from just a single location and strong enough to ensure the site would remain safe for guests to enjoy for many years to come.
The Result
Mainmark pumped 8m3 of self-levelling cement grout into the void from the single access point to re-support the pool slab. Pipes were fed into the back of the void to ensure it was completely filled.
The solution proved highly effective and had little impact on motel operations. The works were completed in the promised timeframe of one day and guests were able to safely use the pool area immediately following the works.
Helen Rainsford, director, Rata Pty Ltd, said: “The project could have seriously impacted the business operations at the motel. Mainmark’s solution resulted in minimal intrusion and works were completed as per planned timelines. Mainmark’s consideration of guests as to when to commence and complete the works was greatly appreciated, and the team was professional and polite. They left the site in pristine condition with not a single drop of product to be found.”
Resources
Project Resources & Downloads
Hazardous Void Beneath A Motel Swimming Pool Filled Using Cement Grout
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