Title Participants Abstract "Fracture mode analysis of cementitious mortars by simultaneous application of 4D-XCT and acoustic emission technique" "Charlotte Van Steen, Jeroen Soete, Mina Sarem, Martine Wevers, Stijn François, Els Verstrynge" "Cementitious brittle construction materials are susceptible to fracturing due to their heterogeneous material composition and relatively weak bond between the aggregates and paste. Hence, enhanced methods of fracture analysis in these materials are an important subject of research. The acoustic emission technique (AET) is frequently used in the study of brittle construction materials, yet the random nature of cracking and the het erogeneity of materials strongly affect the AE results, and necessitates verification of AE data with comple mentary monitoring techniques. Therefore, in this work, a test setup is developed where fracture during Brazilian splitting tests is simultaneously monitored by AE sensors and X-ray computed tomography (XCT). The novel test setup is designed to incorporate AE monitoring into in-situ step-wise load tests of cementitious mortar samples inside an XCT scanner. Digital volume correlation (DVC) of the XCT scans allows in-depth analysis of the fracture mechanism and validation of the AE results. Using DVC the damaged zones with high shear and tensile strain values were identified in addition, the X-ray images were used to investigate the influence of heterogeneities in the overall failure modes. For the AE-based damage localization, three arrival time estimation methods are assessed, with the Akaike Information Criterion (AIC) showing a 50–75% improvement in locating AE sources within the cracked zone. In addition, two AE-based fracture mode analysis methods are compared with the DVC strain field plots. Using both average frequency and rise angle analysis (AF/RA) and peak frequency (PF) analysis, 80–100% AE events in the shear strain zone were able to be classified as shear mode. PF showed better performance in the early load stages while AF/RA showed consistent results throughout. In general, the shear and tensile crack mode classification of the AE events agreed well with the shear and tensile strain field plots." "UV-Curing Assisted Direct Ink Writing of Dense, Crack-Free, and High-Performance Zirconia-Based Composites With Aligned Alumina Platelets" "Shuigen Huang, Jeroen Soete, Bart Van Meerbeek, Jef Vleugels, Fei Zhang" "Additive manufacturing (AM) of high-performance structural ceramic components with comparative strength and toughness as conventionally manufactured ceramics remains challenging. Here, a UV-curing approach is integrated in direct ink writing (DIW), taking advantage from DIW to enable an easy use of high solid-loading pastes and multi-layered materials with compositional changes; while, avoiding drying problems. UV-curable opaque zirconia-based slurries with a solid loading of 51 vol% are developed to fabricate dense and crack-free alumina-toughened zirconia (ATZ) containing 3 wt% alumina platelets. Importantly, a non-reactive diluent is added to relieve polymerization-induced internal stresses, avoid subsequent warping and cracking, and facilitate the de-binding. For the first time, UV-curing assisted DIW-printed ceramic after sintering reveals even better mechanical properties than that processed by a conventional pressing. This is attributed to the aligned alumina platelets, enhancing crack deflection and improving the fracture toughness from 6.8 ± 0.3 MPa m0.5 (compacted) to 7.4 ± 0.3 MPa m0.5 (DIW). The four-point bending strength of the DIW ATZ (1009 ± 93 MPa) is also higher than that of the conventionally manufactured equivalent (861 ± 68 MPa). Besides homogeneous ceramic, laminate structures are demonstrated. This work provides a valuable hybrid approach to additively manufacture tough and strong ceramic components." "Widespread development of bedding-parallel calcite veins in medium-high maturity organic-rich lacustrine shales (Upper Cretaceous Qingshankou Formation, Northern Songliao Basin, NE China): Implications for hydrocarbon generation and horizontal compression" "Rudy Swennen" "Importance of arsenic bioaccessibility in health risk assessment based on iron “Minette” rocks and related soils" "Hannes Claes, Valérie Cappuyns, Rudy Swennen" "Total element concentrations by themselves are not always good predictors of toxicity and are therefore not suitable for eco- and/or human toxicological risk determination. In addition, despite the growing call for harmonization, countries show significant variation in risk assessment tools, screening/background values, protocols and legal management of soils. By incorporating mobility and bioaccessibility/availability into soil risk assessments, location-specific physico-chemical and geological conditions can be considered in routinely applied general risk assessment methodologies. Minette soils and rocks are a great case in point since they often are associated with high geogenic As concentrations and consequently potential risks. Minette iron ores form the world largest Fe ore deposits since the “great oxidation”. For the first time, oral bioaccessibility during direct ingestion was assessed on Minettes from Luxembourg by applying the in vitro Solubility/Bioavailability Research Consortium (SBRC) method. Out of > 180 samples, 25 representative samples were selected providing a unique dataset which showed an average gastric bioaccessibility of ∼10% (7.8 ± 4.0 mg/kg) of the total As-concentration, with a maximum of 45% (17.9 mg/kg). Of importance is that bioaccessibility of As in Minette rocks and soils are controlled by, and can be estimated from, lithology, mineralogy and total Ca content. Soils and ooid grainstones with an iron oxide or clayey matrix, are characterized by average gastric bioaccessible As concentrations < 6 mg/kg. Gastric As bioaccessibility is highest in Fe-bearing calcite-cemented bioclastic grainstones (∼12 mg/kg). Importantly, for all samples the maximal bioaccessible As concentrations remain below the threshold from which significant adverse non-carcinogenic and/or carcinogenic health effects are expected. These new results are in strong contrast with what total As concentrations might suggest. Considering bioaccessibilities, consequently, can help to avoid disproportionate, costly and environmentally impacting risk management strategies. Furthermore, this study illustrates the importance of cross-disciplinary collaboration between geo- and health scientists." "3D printing of an iron-rich slag based hybrid mortar. A durable, sustainable and cost-competitive product?" "Jeroen Soete, Michiel Giels, Yiannis Pontikes" "Ultrasonication optimisation and microstructural characterisation for 3D nanoparticle dispersion in thermoplastic and thermosetting polymers" "Ruben Windey, Jeroen Soete, Yentl Swolfs, Martine Wevers" "Tailoring the theory of critical distances to better assess the combined effect of complex geometries and process-inherent defects during the fatigue assessment of SLM Ti-6Al-4V" "Jeroen Soete" "In-situ X-ray computed tomography of mode I delamination in carbon-epoxy composites: The effect of the interface ply orientation" "Thanasis Chatziathanasiou, Jeroen Soete, Larissa Gorbatikh, Mahoor Mehdikhani" "Linking sedimentary properties to mechanical characteristics of carbonate reservoir rock: An example from central Persian Gulf" "Hannes Claes, Rudy Swennen" "Review of the origin of breccias and their resource potential in the central Africa Copperbelt" "Rudy Swennen, Philippe Muchez"