strength
In the world of concrete science and application, innumerable variables have an influence on whether a concrete installation is successful or not. These include but are not limited to the skill of the applicator, the suitability of the mix design, the temperature at the time of application, the equipment used, the water-to-cement ratio and the size of the aggregate. For all the seeming complexity, however, the nature of the material itself invests the process with a few immovable facts. One of these directly undermines the swimming pool industry’s “standard” that calls for a compression strength of 2,500 pounds per square inch for pneumatically placed concrete (that is, gunite or shotcrete). It’s not because the standard is inadequate per se; rather, it’s because
Every so often, our company is confronted by the belief among certain design professionals that, as it is used by the pool industry, shotcrete is simply not viable for use as structural concrete in high-profile watershaping projects. The assumption, I’ve learned, is that the pool industry is filled with contractors and specification writers who know little about the material and therefore tend to produce substandard results. I could argue the merits of the case, but let it suffice to say that the upshot of this widespread belief is that institutions and commercial clients hesitate to use shotcrete and instead prefer cast-in-place concrete, which they perceive as having greater quality and reliability in watershape applications. We at Drakeley Swimming Pool Co. (Bethlehem, Conn.) recently encountered exactly that prejudice: A private high school that was in the process of designing and building a state-of-the-art aquatic center and an
In the parlance of those who know best, it's time to discuss "mud" - the concrete material out of which most watershape shells are made. Mud enters the scene after the steel, plumbing, electrical conduits and forms have been placed and, in some jurisdictions, all work to that point has passed careful inspection. The concrete itself can take any of four forms: concrete block or poured-in-place concrete (neither of which is used very often), or gunite or shotcrete (far more commonly used). In my three decades of building watershapes, I've worked with all of these materials. If a very specific set of circumstances calls for the use of
In the parlance of those who know best, it's time to discuss "mud" - the concrete material out of which most watershape shells are made. Mud enters the scene after the steel, plumbing, electrical conduits and forms have been placed and, in some jurisdictions, all work to that point has passed careful inspection. The concrete itself can take any of four forms: concrete block or poured-in-place concrete (neither of which is used very often), or gunite or shotcrete (far more commonly used). In my three decades of building watershapes, I've worked with all of these materials. If a very specific set of circumstances calls for the use of
One certainly emerges from all the discussions that have taken place about swimming pool plaster over the past several years: The product has had plenty of room for improvement. Among the complaints has been that traditional white-plaster pool finishes simply haven't kept pace with the rising expectations of owners, who increasingly want their pools, spas and waterfeatures to be entirely forgiving when their lifestyles limit the time they can spend on maintenance and upkeep. In that environment, in fact, traditional
