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The global emphasis on reducing greenhouse gas emissions means that engineers and architects are increasingly required to account for embodied carbon in their designs. However, there is a lack of knowledge and tools in the structural engineering community to enable calculation of embodied carbon for reinforced concrete structures. This paper aims to address this concern by providing a review of the most up-to-date approaches for calculating embodied carbon as well as the important factors that engineers should consider during the design phase to reduce embodied carbon. Environmental product declarations for concrete in four Canadian provinces will also be compared to illustrate the variability in the embodied carbon and the factors that influence this variability. Finally, the paper will present a case-study on the design of a reinforced concrete beam to demonstrate how to calculate embodied carbon and to illustrate how changes in design can influence the total embodied carbon. [ABSTRACT FROM AUTHOR]

Distributed fiber optic sensors (DFOS) allow for the measurement of distributed strains on concrete surfaces and along steel reinforcement in reinforced concrete (RC) members, and these measurements can quantify reinforcement and concrete behavior. In this investigation, concrete surface and reinforcement strains from DFOS were used to quantify and compare the structural behavior of lightly and moderately reinforced one‐way slabs strips to better characterize localized strain behavior of lightly reinforced RC members with small diameter bars (10 M). By quantifying the entire compression region and reinforcement strain behavior, various structural parameters, such as curvature, strain profiles over the height at various locations, and neutral axis depth were calculated. From the distributed properties, it was determined that significant differences in behavior existed between moderately and lightly reinforced specimens with small diameter bars, with the lightly reinforced specimen displaying non‐uniform behavior along its length. Differences observed in the lightly reinforced member with small diameter bars include local curvature differences both at a crack and between cracks, local evidence of plane sections not remaining plane, possible different internal cracking mechanisms, amongst other local strain behavior differences, which could have implications for future modeling and design of lightly reinforced RC members with small diameter bars. [ABSTRACT FROM AUTHOR]

Summary: A combined heavy timber–steel structural system has recently been developed for the adaptation of advanced structural braces into tall timber structures. This study investigates the system‐level performance of a seven‐story combined timber–steel friction‐braced frame using hybrid simulation and incremental dynamic analysis (IDA). The IDA results from the hybrid simulations are compared with a numerical model to assess its ability to capture the nonlinear seismic performance of the timber–steel friction‐braced frame. Experimental and numerical IDA results are used to derive fragility curves for interstory and residual drift and assess its collapse probability under different earthquake hazard levels. The hybrid test results show that the timber–steel friction‐braced frame demonstrates excellent seismic performance under a range of ground motion intensities. The experimental results from the hybrid simulations and the experimental fragility curves correlate well with the numerical modeling results. [ABSTRACT FROM AUTHOR]

Wireless minimally invasive bioelectronic implants enable a wide range of applications in healthcare, medicine, and scientific research. Magnetoelectric (ME) wireless power transfer (WPT) has emerged as a promising approach for powering miniature bio-implants because of its remarkable efficiency, safety limit, and misalignment tolerance. However, achieving low-power and high-quality uplink communication using ME remains a challenge. This paper presents a pulse-width modulated (PWM) ME backscatter uplink communication enabled by a switched-capacitor energy extraction (SCEE) technique. The SCEE rapidly extracts and dissipates the kinetic energy within the ME transducer during its ringdown period, enabling time-domain PWM in ME backscatter. Various circuit techniques are presented to realize SCEE with low power consumption. This paper also describes the high-order modeling of ME transducers to facilitate the design and analysis, which shows good matching with measurement. Our prototyping system includes a millimeter-scale ME implant with a fully integrated system-on-chip (SoC) and a portable transceiver for power transfer and bidirectional communication. SCEE is proven to induce >50% amplitude reduction within 2 ME cycles, leading to a PWM ME backscatter uplink with 17.73 kbps data rate and 0.9 pJ/bit efficiency. It also achieves 8.5 × 10 -5 bit-error-rate (BER) at a 5 cm distance, using a lightweight multi-layer-perception (MLP) decoding algorithm. Finally, the system demonstrates continuous wireless neural local-field potential (LFP) recording in an in vitro setup.