Indoor Vertical Farms (IVF) can contribute to urban circular food systems by reducing food waste and increasing resource use efficiency. They are also known for high energy consumption but could potentially be improved by integration with buildings. Here, we aim to quantify the environmental performance of a prospective building-integrated urban farm. We performed a Life Cycle Assessment for a unit installed in a university campus in Portugal, producing broccoli microgreens for salads. This technology integrates IVF, product processing and Internet of Things with unused space. Its environmental performance was analyzed using two supply scenarios and a renewable energy variation was applied to each scenario. Results show that the IVF system produces 7.5 kg of microgreens daily with a global warming potential of 18.6 kg CO2e/kg in the case of supply direct on campus, or 22.2 kg CO2e/kg in the case of supply off campus to retailers within a 10-km radius. Consistently in both scenarios, electricity contributed the highest emission, with 10.03 kg CO2e/kg, followed by seeds, with 4.04 kg CO2e/kg. The additional use of photovoltaic electricity yields a reduction of emissions by 32%; an improvement of approximately 16% was found for most environmental categories. A shortened supply chain, coupled with renewable electricity production, can contribute significantly to the environmental performance of building-integrated IVF.

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This paper presents an experimental study about the use of innovative bio-based pultruded carbon-fiber-reinforced polymer (CFRP) laminates for structural strengthening. The bio-based laminates were produced in the framework of an applied research project (BioLam) using a resin system with 50% (wt.%) bio-based content, obtained from renewable resources. In the first part of the study, their tensile and interlaminar shear properties were characterized and compared with those of conventional oil-based CFRP laminates. In the second part of the study, the bond behavior to concrete of both types of CFRP laminates applied according to the externally bonded reinforcement (EBR) technique was assessed by means of single-lap shear tests performed on CFRP-strengthened concrete blocks; the experimental results obtained from these tests were then used in a numerical procedure to calibrate local bond vs. slip laws for both types of laminates. The final part of this study comprised four-point bending tests on full-scale EBR-CFRP-strengthened reinforced concrete (RC) beams to assess the structural efficacy of the bio-based laminates; these were benchmarked with tests performed on similar RC beams strengthened with conventional CFRP laminates. The results obtained in this study show that the (i) material properties, (ii) the bond behavior to concrete, and (iii) the structural efficacy of the developed bio-based CFRP laminates are comparable to those of their conventional counterparts, confirming their potential to be used in the strengthening of RC structures.

<p>Strengthening reinforced concrete (RC) members with Carbon Fiber Reinforced Polymer (CFRP) solutions is currently a widespread technique. The success in increasing the strength and/or in controlling the deformation of structural members using CFRPs has been recognized worldwide, and most relevant aspects have been thoroughly studied and published. For large-span beams and slabs, the method is much more effective if pre- stressed CFRP laminates are adopted. Therefore, onsite measurements of the applied strain state, as well as of its evolution with time due to pre-stress losses, are mandatory to ensure a correct operation and to monitor the time-dependent behavior. Presently, the former is assessed only indirectly, through load control when pre-stress is applied, and the latter simply is not conducted since there is no budget to comply with.</p><p>In this paper a first step of a vision-based method to measure the strain level in CFRP laminates during the strengthening operations, as well as during periodic inspections later on, is presented. The method uses computer vision and was applied and validated in computational simulations. The results achieved allowed to establish the limits of validation of the algorithms developed and implemented. The contactless method proposed will represent a major added value for the already widespread technique of reinforcement of RC members with pre-stressed CFRP laminates.</p>