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1H and 13C nuclear magnetic resonance spectra were recorded on a Bruker Avance III 400 or Magritek Spinsolve 60 spectrometer at 293 K. Chemical shifts are reported as δ in parts per million (ppm) and referenced to the chemical shift of the residual solvent resonances (CDCl3: 1H: δ = 7.26 ppm, 13C: δ = 77.16 ppm). Polymer molecular weight and dispersity were determined using a Malvern Viscotek GPCmax size exclusion chromatograph instrument fitted with a Viscotek TDA 305 detector unit equipped with refractive index and light scattering detectors. Samples were dissolved in tetrahydrofuran at a concentration of approximately 1 mg mL-1 and eluted through a guard column and two Agilent PLGel 5 µm mixed C columns (300 x 7.5 mm) at a flow rate of 1 ml.min-1; the elution pathlength was heated to 30 °C for the duration. Molecular weights were calibrated against known poly(methyl acrylate) standards. Differential scanning calorimetry was conducted using a TA Instruments Discovery 2500. Samples were analysed in non-hermetic aluminium pans and compared against an empty reference pan of the same type. Loaded sample masses were between 3 and 10 mg. Samples were subjected to two complete heat/cool cycles from -50 °C to 150 °C (-85 °C to 150 °C for lower Tg samples) and both heating and cooling rates were set at 10 °C min-1. UV/Vis transmittance and absorption spectra were measured with a PerkinElmer Lambda 750 spectrophotometer. Transmittance spectra of films were measured using wavelength scan with a resolution of 1 nm at a scan speed of 267 nm/min and a slit width of 2 nm. Samples were directly mounted to the sample holder. Solution spectroscopy was carried out on solutions in THF in quartz SUPRASIL® cuvettes (10 mm pathlength). Absorption spectra of luminophore solutions were taken using a wavelength scan with a resolution of 0.5 nm at a scan speed of 141.20 nm/min and a slit width of 2 nm. A reference sample of THF in an identical cuvette was used to apply a 100% transmission correction. Steady-state PL spectroscopy was performed on a Fluorolog-3 spectrophotometer (Horiba Jobin Yvon). Solid-state emission spectra were recorded using the front-face configuration. Solution emission spectra were recorded using the right-angle configuration, over 10 averaged scans. The excitation and emission slits were adjusted so that the maximum PL intensity was within the range of linear response of the detector and were kept the same between samples if direct comparison between the emission intensity was required. Emission and excitation spectra were corrected for the wavelength response of the system and the intensity of the lamp profile over the excitation range, respectively, using correction factors supplied by the manufacturer. Photoluminescence quantum yields (ΦPL) were measured using a Quanta-phi integrating sphere (Horiba Jobin Yvon) mounted on the Fluorolog-3 spectrophotometer. The UC emission and phosphorescence spectra, threshold intensity (I_th), UC quantum yield (UC) and lifetime measurements were performed using an FLS1000 time-correlated single photon counting (TCSPC) spectrometer (Edinburgh Instruments Ltd.). The samples were excited with a 532 nm laser (MGL-III-532, 200mW). To determine I_th, the laser power was adjusted using a Thorlabs PM100A Power Meter Console combined with a S120VC Si photodiode power sensor (range: 200-1100 nm) before the measurement, across the 5 to 8000 mW cm-2. The ΦUC was measured with an integrating sphere (SNS125 5-inch sphere, three windows, International Light Technologies). The sample was placed at the center of the sphere using a sample holder. A baffle is placed in front of the observation window, which blocks any scattering and reflection of the laser from the sample surface. The angle of the sample holder is adjustable. The normal direction of the sample holder is 22.5˚ to the excitation beam line, which leads the reflection of the laser to the inner surface of the sphere. The laser power was measured with a photodiode before each ΦUC measurement. Both the emission of the sample (380-500 nm) and scattering of the laser beam (530-534 nm) were measured. A neutral density filter (O.D.=3.0) was placed before the excitation beam for the scattering intensity measurements. Six data sets were collected to calculate the ΦUC of each sample: 1. sample in the path of the beam – “in fluorescence”; 2. sample in scattering; 3. sample facing away from beam – “out of fluorescence”, 4. sample out of scattering; 5. empty sphere fluorescence; 6. empty sphere scattering. Fluorescence decay measurements were performed using the multi-channel scaling (MCS) method on a the FLS1000 TCSPC spectrometer. The emission decay was recorded using a photomultiplier tube (PMT-980) equipped with TCC2 counting electronics. For the upconversion lifetime measurements, a wavelength of 440 nm was selected, and a short-pass filter (cut-off at 500 nm, Thorlabs) was placed in front of the detector. For the phosphorescence lifetimes, a wavelength of 660 nm was selected, and a long-pass filter (cut-off 550 nm, Thorlabs) was used. The instrument response function (IRF) was measured using Ludox® colloidal silica solution (a SiO2 particle suspension solution) and using a neutral density filter (O.D.=3) to attenuate the laser intensity. The pulse repetition rate was adjusted to ensure the full decay was detected within the time window. Data-fitting was carried out by tail fitting to each emission decay trace using a multiexponential decay function within the FAST software package (Edinburgh Instruments Ltd.). The goodness of fit was evaluated using the reduced chi-square statistics (χ2) and the randomness of the residuals. Please also see the readme file for more details on data collection and file organisation.

Concrete is the world’s most used construction material. There are significant challenges with the decarbonisation of concrete, particularly cement, due to the release of carbon dioxide emissions during clinker production. Therefore, strategies to reduce embodied carbon in concrete buildings should aim to focus on material efficiency efforts first. Existing relationships between concrete and embodied carbon, such as increased concrete strength, increasing global warming potential (GWP), increased span length increasing GWP, and taller buildings generally having higher carbon have been investigated. However, some relationships are yet to be explored. These include the relationship of form and associated structural layouts to embodied carbon. One of the challenges of conducting embodied carbon assessments is the selection of material embodied carbon coefficients (ECCs). This is particularly true during early-stage design when the specific material selection is still unknown. A common early-stage technique for identifying embodied carbon reduction strategies is identifying carbon hotspots. However, these hotspots can be heavily influenced by the large variation in environmental product declarations (EPD) across manufacturers and differing product specifications. Without quantifying this uncertainty due to material ECC uncertainty, selecting the most likely lowest-impact design option is challenging. The most common approach for uncertainty propagation is to use Monte Carlo (MC) simulations. This propagation provides results as a distribution instead of a single, deterministic result. It is simple to compare single-value results to demonstrate the difference between design options and select the lowest-impact alternative. However, using uncertainty statistical methods to compare structural frame designs against each other and also against industry benchmarks is yet to be investigated. Therefore, comparative statistical methods are evaluated for their suitability in early-stage decision-making and, specifically, structural frame design comparisons. This thesis introduces a newly-proposed methodology that propagates uncertainties in material quantities and ECCs during early-design comparisons. The methodology incorporates a novel ranking step to identify key contributing materials, streamlining assessments by reducing time and focusing on material hotspots. A new uncertainty characterisation of construction materials is introduced, utilising statistical parameters from an industry material ECC database. The thesis later integrates quantity uncertainty by design stage with material ECC uncertainty for early-stage structural EC assessments, capturing incompleteness and variation due to quantity take-off methods and early-stage estimations. Additionally, the thesis introduces a new parametric tool for early-stage concrete frame designs. This tool incorporates form definition (for seven-shaped buildings), followed by a layout derivation for all possible solutions within a span range. Next, a C# script within the tool conducts structural RC design for multiple slab types, and finally, product-stage embodied carbon calculations with uncertainty are presented. An investigation into the influence of architectural form on structural frame layouts and resulting embodied carbon was conducted, considering seven equally-sized shaped forms for two plot sizes. In combining the uncertainty procedure and parametric form design tool, comparative statistical methods for evaluating uncertain results are tested for the first time in a building EC context. Lastly, the thesis concludes by proposing a novel application for comparing structural EC results against the SCORS rating system. By including uncertainty in early-stage building EC assessments, this thesis enables engineers to conduct more reliable and fair comparative EC studies. Relying on average material ECCs (with uncertainty) through early design stages also benefits practitioners by prioritising EC savings through demand reduction and material efficiency without relying on low-carbon products.