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The study provides novel insights on the compressive and tensile strength of high strength engineered cementitious composite (HSECC) at elevated temperatures under in‐situ testing condition. An optimized mix design was employed and cylinder and dogbone specimens were tested to study the compressive and tensile strength of HSECC at elevated temperature. The tested results under in‐situ test condition were compared with the residual state by exposing the specimens to temperature up to 600°C. It was found that specimens under in‐situ condition showed a drastic decrease in compressive strength (26.8%–34.5%) at 200°C and the performance was much inferior to that observed for residual state which showed only 12.2% decrease. This trend was consistent for both tensile and compression test results. After this, the in‐situ specimens underwent slight increase in the compressive strength with only around 25% decrease at 400°C and 14%–16% decrease at 600°C. However, the residual state specimens underwent continuous decrease in strength. Therefore, this study confirmed that for high strength cementitious composites exposed to elevated temperatures, the residual test results should not be considered as the lower limit and in‐situ testing results are essential for accurately predicting the behavior of cementitious composites. Thus, this research underscores the importance of conducting both in‐situ and residual state tests in the design of HSECC structural members. [ABSTRACT FROM AUTHOR]

Nowadays, academics and industrial practitioners widely consider additive manufacturing systems to enhance overall production and operational effectiveness and efficiency, owing to the concepts of Industry 4.0 and 5.0. This paper proposes a structural equation model to evaluate the impact of customisation experience and perceived value within a data-driven additive manufacturing system. To deepen the understanding of customer-perceived value and its connection to additive manufacturing, this study defines four new sources of perceived value: reliability, performance, aesthetics, and features. All of these new values are based on utilitarian value, and four of them exhibit statistical significance in relation to utilitarian value. In order to apply these new values to additive manufacturing, it is necessary to conduct mechanical testing and studies to identify the ideal parameter set for 3D printing that aligns with customer-perceived value regarding these new values. [ABSTRACT FROM AUTHOR]

This study examines the existing knowledge that pre-service elementary teachers (PSETs) have regarding heat energy, heat transfer and insulation. The PSETs' knowledge of heat energy was initially assessed by using an activity: determining which container would be best to keep hot water warm for the longest period of time. Results showed that PSETs could not explain the concept of insulation and heat transfer. Moreover, they held the misconception that a container deemed best to keep water warm would not be the best container to keep ice cream cold. To reconcile the misconceptions of PSETs, the researcher used the ED3U Conceptual Change Model (McComas, 1995) integrated with Posner, Strike, Hewson and Gertzog's (1982) conditions for accommodations for the designed instruction and discussions. Results show PSETs can understand the concepts better when analogy and daily life experiences are used.

Many studies have suggested that engineered cementitious composite (ECC) could be a highly efficient and cost‐effective material for enhancing the flexural strength of reinforced concrete (RC) beams. Recently two effective retrofitting configurations using steel and polyvinyl‐alcohol hybrid fiber reinforced engineered cementitious composite (SPH‐ECC) were proposed (Qasim et al., Eng Struct, 2023, 284, p. 115992) and their high effectiveness for enhancing the flexural strength of RC beam was verified experimentally. However, to examine the performance of these strengthening configurations thoroughly by conducting experiments to cover practical ranges of design parameters is deemed to be too expensive and time consuming. In this study, a numerical parametric study of SPH‐ECC strengthened RC beams was conducted by employing a validated finite element (FE) modeling procedure developed by the authors. The effects of four key design parameters including the compressive strength of concrete and SPH‐ECC, the thickness of SPH‐ECC strengthening layer and the area of reinforcement bars embedded in SPH‐ECC layers on the flexural performance of the strengthened beams were studied. Parametric study results showed that the area of reinforcement bars in the SPH‐ECC layers could significantly affect the flexural strength of the strengthened beams. Furthermore, in order to allow engineers to predict the flexural strength of the strengthened beams quickly, two simple but accurate analytical models were also developed for the two strengthening configurations considered. Their reliability and accuracy were then verified and confirmed by comparing with the parametric study results. [ABSTRACT FROM AUTHOR]