Rheological study of long-term deflection in onyx waste concrete

Long-term deflection is the deflection occurred as a function of time and is influenced by several factors such as humidity, temperature, treatment conditions, stress-strength ratio, age of concrete, and so on. This study aimed to analyze the long-term deflection of reinforced concrete beams with onyx waste aggregates and normal aggregates using Gibson R.E & Lo.KY rheological model analysis. The test used reinforced concrete beams with dimensions of 15 x 25 x 200 cm, with a loading duration of two weeks. Based on the results of the experimental tests and the analysis of rheological models, it was found that the deflection value of reinforced concrete beams with onyx stone waste aggregate was greater than that of reinforced concrete beams with normal aggregates. It was indicated by the deflection value obtained from the experimental test for two weeks of loading on the onyx beam of 0.315 cm, and the value of the rheological model prediction was 0.315 cm. The deflection value obtained from the experimental test for two weeks of loading on a normal beam was 0.220 cm, and the value of the rheological model prediction was 0.220 cm. This showed that the results of the rheological model analysis can be used to predict the long-term deflection of reinforced concrete beams.