notice a disparity between the compressive strength of the fabric formed concrete (denoted by the F of FAC) and the two cylinders formed in cardboard (NC2 and NC1). As seen on the graph, on day 28, the average compressive strength of the fabric formed concrete was around 39MPa, whereas the average for the normal concrete examples ranged between 27MPa and 31MPa (Figure 1).The cylinder tests showed an average increase in compressive strength equal to around 15%, which is a decidedly notable improvement.This is because the permeable membrane of the fabric let excess water seep out of the concrete, unlike in traditional moulding methods, and therefore reduces the concrete’s cement to water ratio. Due to the reduction in this ratio, a “higher compressive strength in fabric formed concrete is achieved” (West, 2015). I think that this alludes to an incredibly significant benefit - if the concrete we use is stronger, the buildings are more structurally secure and less likely to experience stability problems.As this research was conducted mainly by Mark West, who pioneered the fabric formwork technique and teaches it as a subject in a research centre he leads (CAST), the research has high credibility as he is the leading expert in the topic.
opposed to regular methods of forming concrete, such as: a higher capacity for load- bearing and more strength, and the capability of more efficient concrete usage.These characteristics are most clearly highlighted when in the context of physical examples, where the benefits can be quantified. One instance of this is the experiments run by Mark West, Farhoud Delijani and Dagmar Svecova, where they compared the average compressive strength of concrete cylinders, half of which were made in fabric casts and half of which were set in cardboard moulds. Once the cylinders had fully set, they tested them with loads, which they increased until the cylinders broke or cracked. The load recorded is the maximum load in kilo-Newtons (kN) that the cylinders could withstand.The aim of the experiment was to prove that fabric formwork created stronger concrete with a higher breaking point which, if proved true, would be one of the most significant benefits of formwork, in my opinion. On all 232 comparative samples tested, there was a notable increase in the maximum load that the fabric cast concrete cylinders could withstand before breaking, as opposed to the ones moulded with cardboard.These values were then used to calculate the average compressive strength of each type using the equation: F = P/A Where F is the compressive strength in MPa, P is the maximum load withstood by the material before failure in kN, and A is the cross-sectional area of the structure in m^2. A was kept the same as a control variable, F was the dependent variable that was calculated, and P was the independent variable that was increased until it reached a maximum for each cylinder. This was tested on days: 0, 3, 7, 14, 21, 28 and 56 (as marked by the points on each line in Figure 1).After reading off the graph, I took from the values that, after around day 3, they started to
Figure 1:A graph displaying the test results found by Mark West et al. after their experiments with concrete cylinders.
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