Laboratoire de Génie Civil et Géo Environnement
facilityVilleneuve-d'Ascq, Hauts-de-France, France
Research output, citation impact, and the most-cited recent papers from Laboratoire de Génie Civil et Géo Environnement (France). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from Laboratoire de Génie Civil et Géo Environnement
Atrazine is one of the most widely-used chlorine herbicides in agriculture. In recent years, studies have shown a potential hazard of atrazine use in environmental health and human health. Due to its toxicity, widespread use, relatively high stability in water and soil, determining safe and efficient methods of its removal is crucial. The main aim of this review was to showcase the recent progress of atrazine degradation methods, along with their main advantages, disadvantages, potential efficiency, and degradation pathways. The overall goal was to create an information gateway for researchers, and stakeholders interested in choosing the best method for atrazine degradation. Thus, the current technologies for atrazine degradation are systematically reviewed and can be used for future improvements or the selection of the most appropriate strategy for a specific place.
Cement paste hydration is a complex physical-chemical process. The aim of this paper is to use three approaches to determine the degree of hydration: portlandite quantification, scanning electron microscopy and bound water quantification. In order to investigate the physical-chemical and mechanical properties, as well as the hydrates generated. Portland cement was synthesized and characterized in the laboratory. At all hydration durations, the portlandite quantification method and SEM-BSE image analysis show similar results. The method of SEM images analysis requires time to gather and process images, but is unaffected by the type of hydrates produced. The bound water quantification method gives a lower degree of hydration than two other methods at all hydration times. To test the reliability of these procedures, the compressive strength was calculated based on the degree of hydration. The results indicate that the portlandite quantification method and SEM-BSE image analysis are more accurate than the bound water quantification approach in terms of reproducing the experimental results.
The aim of this research is to determine the mechanical and durability properties of sugarcane bagasse ash (SCBA) as a partial replacement to Ordinary Portland Cement (OPC) in concrete. The SCBA was partially replaced at the percentage of 5 %, 10 %, 15 % and 20 % by weight of cement for a mean target strength of 27 MPa. A slump range of 130–150 mm was maintained constant throughout the experiment procedures. A total of 120 cubes and 30 rectangular beams were tested and the results were compared with control concrete. To evaluate the behaviour of SCBA on concrete, different tests were conducted on the concrete specimens namely, compressive strength, flexural strength, water absorption, water penetration, carbonation and ultrasonic pulse velocity. The results demonstrated that at 120 days of curing, compressive strength increased by 2.6 % and 1.7 % for 5 % and 10 % replacement level. The water absorption increased by 255 %, 390 %, 438 % and 488 % for 5 %, 10 %, 15 % and 20 % replacement level. The other tests showed decreased flexural strength and ultrasonic pulse velocity and increased water penetration and carbonation depth. The study inferred that 10 % replacement of OPC by SCBA exhibited positive performances and can be considered a suitable cementitious material in the construction industry.
Urbanization activity and climate change increase the runoff volumes, and consequently the surcharge of the urban drainage systems (UDS). In addition, age and structural failures of these utilities limit their capacities, and thus generate hydraulic operation shortages, leading to flooding events. The large increase in floods within urban areas requires rapid actions from the UDS operators. The proactivity in taking the appropriate actions is a key element in applying efficient management and flood mitigation. Therefore, this work focuses on developing a flooding forecast system (FFS), able to alert in advance the UDS managers for possible flooding. For a forecasted storm event, a quick estimation of the water depth variation within critical manholes allows a reliable evaluation of the flood risk. The Nonlinear Auto Regressive with eXogenous inputs (NARX) neural network was chosen to develop the FFS as due to its calculation nature it is capable of relating water depth variation in manholes to rainfall intensities. The campus of the University of Lille is used as an experimental site to test and evaluate the FFS proposed in this paper.
First, this article introduces a comparison between experimental results and the results issued from a numerical model of a composite Trombe solar wall incorporating a concrete storage wall with the help of the Dymola/Modelica software. The validation of the model is realized from the comparison between simulated and measured heat flux, external and internal surface temperatures and fluid temperatures in a ventilated air layer. Then, the numerical model is used to simulate a composite solar wall where the concrete storage wall is replaced by a mortar mixed with microencapsulated phase change material (PCM). This allows to study and compare the thermal behavior and the energy performances of the two composite solar walls.
Chlorite, a 2:1:1 phyllosilicate, has all the required attributes to form the basis of a geothermometer: this mineral is ubiquitous in metamorphic, diagenetic, and hydrothermal systems with a broad field of stability and a chemical composition partly dependent on temperature (T) and pressure (P) conditions. These properties led to the development of a multitude of chlorite thermometers, ranging from those based on empirical calibrations (linking T to AlIV content) to thermodynamic or semi-empirical models (linking T to chlorite + quartz + water equilibrium constant). This present study provides an overview of these geothermometers proposed in the literature for low-temperature chlorite (T < 350 °C), specifying the advantages and limitations of each method. Recent analytical developments that allow for circumventing or responding to certain criticisms regarding the low-temperature application of thermometers are also presented. The emphasis is on micrometric and nanometric analysis, highlighting chemical intracrystalline zoning—which can be considered as evidence of a succession of local equilibria justifying a thermometric approach—and mapping ferric iron content. New perspectives in terms of analysis (e.g., Mn redox in Mn-chlorite) and geothermometer (molecular solid-solution model, oxychlorite end-member) are also addressed.
Elderly populations in Asian countries are expected to increase rapidly in the next few decades. Older adults, particularly in high-density cities, spend a considerable amount of time in urban green spaces (UGSs). The World Health Organization noted that UGSs are key to improving the age-friendliness of neighborhoods. Thus, it is necessary to design UGSs for the promotion of healthy ageing to enhance preventive healthcare and relieve medical burdens. This study conducted interviews using a questionnaire with a sample size of 326 participants in the cities of Hong Kong (China) and Tainan (Taiwan region). The inter-relationships among the design of UGSs (e.g., spatial distribution and accessibility, characteristics of plants and UGSs), older adults' perceptions on safety and aesthetics quality of UGSs, and their self-reported health conditions (assessed by the self-reported SF-12v2 Health Survey) were investigated with bivariate Spearman rank correlation tests. The results indicate that the duration of visits to UGSs was positively associated with mental health and social functioning, two subscales evaluating health-related quality of life in SF 12v2. The statistical model (moderation analysis) showed that such a correlation was especially significant in women and those with low social support and social capital. A positive relationship was found between the physical health subscale and perceived safety in UGSs. This relationship was stronger among older adults living alone (moderation analysis). Furthermore, the color of plants and maintenance condition of UGSs were significant aspects affecting the subjective assessment of aesthetic quality. This study provides useful information regarding how to plan and design urban green spaces with certain characteristics that could improve the accessibility and aesthetic quality, which are preferred by older adults.
The amount of bottom ashes generated from the municipal solid waste incineration is increasing considerably. Therefore their recycling is necessary in order to limit the landfilling that presents environmental issues. The aim of this paper is to recycle Municipal Solid Waste Incineration Bottom Ash from the north of France; as a secondary raw material for Portland cement clinker production. In this order Municipal Solid Waste Incineration Bottom Ash is characterized and then used to substitute raw materials for clinker production at laboratory scale. Substitutions rates up to 12.4 % have been tested. The produced clinkers have been characterized by X-Ray Diffraction and the crystalline phases were quantified by Rietveld analysis. The microstructure has been studied by scanning electronic microscopy. After adding gypsum, the compressive strengths of the corresponding cements were measured at 1, 7 and 28 days. The mineralogical composition of the 28 days hydrated cement pastes were studied by X-Ray Diffraction. The results show that up to 12.4 % of Portland cement raw materials can be replaced by the Municipal Solid Waste Incineration Bottom Ash without changing the mineralogical composition. In addition the compressive strengths of the cement pastes produced with Municipal Solid Waste Incineration Bottom Ash are equivalent to the one without bottom ash.
Sharing renewable energies, reducing energy consumption and optimizing energy management in an attempt to limit environmental problems (air pollution, global warming, acid rain, etc.) has today become a genuine concern of scientific engineering research. Furthermore, with the drastic growth of requirements in building and industrial worldwide sectors, the need for proper techniques that allow enhancement in the thermal performance of systems is increasingly being addressed. It is worth noting that using sensible and latent heat storage materials (SHSMs and phase change materials (PCMs)) for thermal energy storage mechanisms can meet requirements such as thermal comfort in buildings when selected correctly. However, as the operating temperature changes, a series of complex technical issues arise, such as heat transfer issues, leaks, corrosion, subcooling, supercooling, etc. This paper reviews the most recent research advances in the area of sensible and latent heat storage through the porous media as potential technology while providing useful information for researchers and engineers in the energy storage domain. To this end, the state and challenges of PCMs incorporation methods are drawn up, and an updated database of various research is provided while discussing the conclusions concerning the sensible and latent heat storage in porous media, their scopes of application and impact on energy consumption. In the light of this non-exhaustive review, it turns out that the adoption of porous matrices improves the thermal performance of systems, mitigates energy consumption and drops CO2 emissions while ensuring thermal comfort within buildings. In addition, at the representative elementary volume (REV) and pore scales, the lattice Boltzmann method (LBM) is examined as an alternative method to the commonly used, traditional numerical methods. These two approaches are compared based on results available in the literature. Through these means, their ability to handle latent and sensible heat storage process in a porous medium is demonstrated. To sum up, to be more complete, perspectives of sensible and latent energy storage technologies are covered.
Membrane-type acoustic metamaterials have received much attention for low-frequency sound manipulation, especially in the form of decorated membrane resonators. In this paper, such resonators are obtained using fused deposition modeling. Beyond the practical aspects provided by this manufacturing method, the low density of the flexible filament used increases their effectiveness. Indeed, the mass usually added to the membrane center can easily be divided into several disjoint elements. Using rotary inertia of the added structures, new peaks of efficiency in both absorption and normal transmission loss appear when compared to usual decorated membrane resonators.
Occupant health can be strongly influenced by indoor air quality due to time spent indoors (90%). Such quality can be impacted by indoor atmospheric pollutants present. Therefore, demand-controlled ventilation can be a key to improving indoor air quality. The main aim herein is to scrutinize measurement results of several air pollutants possibly existing inside university building including CO 2 , volatile organic compounds, formaldehyde, benzene, CO, PM 2.5 during three measurement campaigns (March 2017, May 2017 and October–November 2017) via a smart sensor specially developed. Likewise, some factors to assess comfort such as relative humidity and ambient air temperature were examined. CO 2 were found to be higher during periods of occupancy with concentrations exceeding 2000 ppm during the first campaign. As a result, the occupants felt uncomfortable. Analysis of the survey results regarding the indoor air temperature showed that 80% of occupants found the temperature during school periods to be uncomfortable. In addition, the ICONE air containment index was extremely high, indicating that the deemed class was confined during occupancy. The outcomes will be useful for the development of future indoor air quality guidelines, ventilation design and occupant satisfaction in buildings.
The global diversity of fungi has been estimated between 2 to 11 million species, of which only about 155 000 have been named. Most fungi are invisible to the unaided eye, but they represent a major component of biodiversity on our planet, and play essential ecological roles, supporting life as we know it. Although approximately 20 000 fungal genera are presently recognised, the ecology of most remains undetermined. Despite all this diversity, the mycological community actively researches some fungal genera more commonly than others. This poses an interesting question: why have some fungal genera impacted mycology and related fields more than others? To address this issue, we conducted a bibliometric analysis to identify the top 100 most cited fungal genera. A thorough database search of the Web of Science, Google Scholar, and PubMed was performed to establish which genera are most cited. The most cited 10 genera are Saccharomyces , Candida , Aspergillus , Fusarium , Penicillium , Trichoderma , Botrytis , Pichia , Cryptococcus and Alternaria . Case studies are presented for the 100 most cited genera with general background, notes on their ecology and economic significance and important research advances. This paper provides a historic overview of scientific research of these genera and the prospect for further research.
The density functional theory-based calculations were performed on stripe models of the single kaolinite layer. The calculations helped to explain why halloysite mineral, a member of the kaolinite group existing in a tubular form, has rolled tubes only in one way. In that form, aluminol octahedral sheet, terminated by surface hydroxyl groups, represents the inner surface of the nanotubes. The bending models with the inner surface formed by the SiO tetrahedral sheet showed significant structural instability with monotonically increasing strain energy as a function of the curvature. In contrast, for the bending models with the octahedral sheet as the inner surface, stabilization energetic minima were found at curvatures of about 10 nm. The calculations were also performed on the individual sheets (tetrahedral and octahedral) of the kaolinite layer to show their contribution to the bending strain. We found that the decrease of the bending energy and the layer stabilization with respect to the planar configuration for curvatures with radii RC > ∼5 nm can be attributed mainly to three factors—(i) better match between octahedral and tetrahedral sheets, (ii) local structural changes of the SiO and AlOH polyhedral units, and (iii) increasing effectivity of hydrogen bonding of the outer surface OH groups.
Thermal energy storage (TES) using phase change materials (PCMs) is an innovative approach to meet the growth of energy demand. Microencapsulation techniques lead to overcoming some drawbacks of PCMs and enhancing their performances. This paper presents a comprehensive review of studies dealing with PCMs properties and their encapsulation techniques. Thus, it is essential to critically examine the existing techniques and their compatibility with different types of PCMs, coating materials, and the area of application. The main objective of this review is to describe each microencapsulation process and to determine different factors that influence the performance of resulting microcapsules. Microencapsulation efficiency, as well as the limitation of each technique, are investigated, and optimum operating conditions of each process are highlighted. Furthermore, up-to-date studies of multifunctional PCMs microcapsules development with enhanced performances and new application directions are also presented. This review aims to be a useful guide for future researches dealing with low thermal energy storage applications of PCMs microcapsules.
Plastic wastes and their fragments (microplastics, MPs < 5 mm) represent a global, persistent, and ubiquitous threat to ecosystems. Their sources, transfers, and fates are still poorly understood, especially in rivers. To fill this gap, sediments were collected from two dredging disposal sites along the Aa River (France). Four pits were dug, and triplicate samples were obtained at four depths (down to 140 cm). The sediments were sieved to 5 mm to collect macroplastics (MaPs). MPs were separated from the sediment based on density using a NaI solution (1.6 g/mL). Suspected plastics were analyzed with Fourier transform infrared spectroscopy. The studied sediments were found to be widely contaminated with concentrations ranging from 0.97 to 77 MaPs/kg and from 0.78 to 2800 MPs/kg, which were 1-4 orders of magnitude lower than those in most polluted European riverbeds. The MaPs were principally polyethylene, polypropylene, polystyrene, and polyvinyl chloride films, whereas the MPs were mainly polyamide and polyester fibers. The plastic concentrations and features of the two sites, which were filled at two different times, differed. Several factors occurring before and after dredging operations may explain these discrepancies. Nevertheless, no relationships with the sediment features were noted, and thus, one major driving force could not be identified. At the site scale, more than 1 ton of plastic could be stored. In conclusion, this study highlights the importance of dredged sediments for past plastic pollution studies and global plastic budget estimations.
This article presents a micromechanics-based model that constitutively relates internal network physics of hydrogel-based nanocomposites with their visco-super-elastic mechanics. The model is based on the Eshelby inclusion theory combined to the concept of cubic material volume to take into account the effective role of inorganic nanoparticles on the finite-strain response of hydrogels. Dynamic bonds between hydrogel chains and nanoparticles allow to describe the impressive time-dependent properties of hydrogel-based nanocomposites such as rate-dependent extreme stretchability, strong hysteresis upon stretching-retraction and room temperature self-healing facility. The model is compared to a few available experimental data of a variety of hydrogel-nanofiller material systems in terms of stress-strain response till failure, hysteresis, continuous relaxation and self-healing. The effects on the hydrogel behavior of loading conditions (strain rate and strain level) and internal network structures (due to variations in reinforcing elements and cross-linker amounts) are examined. The micromechanical model simulations are found in excellent agreement with experimental observations showing the relevance of the proposed approach. The mechanisms of nanofillers reinforcement and failure are discussed with respect to the model. The room temperature self-healing characteristics of hydrogel systems are discussed in connection to loading history and nanostructure. To further illustrate the model capabilities, the behavior of hydrogel systems is finally treated under different biaxial loading conditions.
The advance rate (AR) is a significant parameter in shield tunneling construction, which has a major impact on construction efficiency. From a practical perspective, it's helpful to establish a predictive model of the AR, which takes into account the instantaneous parameters as well as the past operations. However, for shield tunneling in mixed ground conditions, most researches focused on the average values of AR per ring and neglect the influence of past operations. This article presents a long short-term memory (LSTM) recurrent neural network model, which was developed for the slurry shield tunneling in a mixed ground of round gravel and mudstone in Nanning metro. A temporal aggregated random forest is employed to rank the importance of the explanatory features. The model performances in different ground conditions are investigated. The results show that the LSTM model can be effectively implemented for the AR prediction. A high correlation is observed between predicted and measured AR with a correlation coefficient ($R^{2}$ ) of 0.93. The LSTM based AR predictive model is compared with the random forest (RF) model, the deep feedforward network (DFN) model, and the support vector regression (SVR) model. The comparison shows that the LSTM model has the best performances compared to other models. With one-fourth features, we can achieve a 95% prediction accuracy measured by the $R^{2}$ in the proposed model.
The present article is discussing the performance of heat transfer enhancement (HTE) using a trapezoidal vortex generator in a Concentric Tube Heat Exchanger (CTHE) through Computational Fluid Dynamics (CFD) code ANSYS Fluent. Heat transfer and fluid flow analysis are conducted for various Reynolds numbers inside the tube and annular. The effects of Vortex Generators (VGs) are studied as well, and the turbulence flow is simulated using the k-ꞷ model. The analysis was made on four designs, where the VGs are placed in three different locations as follows: (case 0) no VGs, (case 1) VGs inside the tube, (case 2) VGs on the interface between annular and tube, and (case 3) VGs on the outer wall of the annular part. Accordingly, the overall heat transfer, heat transfer ratio, and heat transfer/power of each of the three cases with VGs are normalized to case 0 to study the effect of VGs on the flow and heat transfer enhancement. Results show that VGs are effective in all locations and cases, however, the highest improvement was spotted in case 1 at Reynolds number of 8000 for the cold fluid and Reynolds number of 2000 for the hot water, where the enhancement of heat transfer ratio was 97% for case 1, 92% for case 2 and 56% for case 3, whereas the thermal enhancement factor was 210% for case 1, 180% for case 2 and 142% for case 3.
Cryptosporidium is an apicomplexan parasitic protist, which infects a wide range of hosts, causing cryptosporidiosis disease. In farms, the incidence of this disease is high in animals such as cows, leading to extensive economic loss in the livestock industry. Infected cows may also act as a major reservoir of Cryptosporidium spp., in particular C. parvum, the most common cause of cryptosporidiosis in these animals. This poses a risk to the trading of livestock, to other farms via breeding centres, and to human health. This study is a part of a global project aimed at strategies to tackle cryptosporidiosis. To reach this target, it was essential to determine whether prevalence was dependent on the studied countries or if the issue was borderless. Indeed, C. parvum occurrence was assessed across dairy farms in certain regions of Belgium, France, and the Netherlands. At the same time, the animal-to-animal transmission of the circulating C. parvum subtypes was studied. To accomplish this, we analysed 1084 faecal samples, corresponding to 57 dairy farms from all three countries. To this end, 18S rRNA and gp60 genes fragments were amplified, followed by DNA sequencing, which was subsequently used for detection and subtyping C. parvum. Bioinformatic and phylogenetic methods were integrated to analyse and characterise the obtained DNA sequences. Our results show 25.7%, 24.9% and 20.8% prevalence of Cryptosporidium spp. in Belgium, France, and the Netherlands respectively. Overall, 93% of the farms were Cryptosporidium positive. The gp60 subtyping demonstrated a significant number of the C. parvum positives belonged to the IIa allelic family, which has been also identified in humans. Therefore, this study highlights how prevalent C. parvum is in dairy farms and further suggests cattle as a possible carrier of zoonotic C. parvum subtypes, which could pose a threat to human health.
Supravital species identification of morphologically similar syntopic earthworms inhabiting dung and compost heaps or those from commercial cultures is difficult. The aim of the studies was to find out non-invasive species-specific markers for proper segregation of earthworm species from a dense mixed colony of waste decomposers. Worms were segregated according to external characteristics into Eisenia andrei, Eisenia fetida, and Dendrobaena veneta, and left for reproduction and analysis of non-invasively retrieved coelomocyte-containing coelomic fluid and/or species-specific partial sequences of cytochrome c oxidase subunit I (COI) gene in DNA extracted from amputated tail tips of adults and their offspring. Flow cytometric analysis of coelomocyte samples revealed that amount of nuclear DNA increases in order D. veneta ≪ E. andrei < E. fetida, and intensity of eleocyte-derived fluorescence is lower in D. veneta than in Eisenia spp. Spectrofluorimetry of coelomocyte lysates revealed that the amount of eleocyte-stored riboflavin is significantly lower in coelomocyte lysates from D. veneta than from Eisenia spp., and the emission peak of X-fluorophore is much more distinct in D. veneta than in Eisenia spp. Coelomic fluid of E. andrei exhibits a very distinct spectra of MUG fluorophore which are absent in D. veneta and in the majority of E. fetida, while some E. fetida possess MUG-like fluorophore. Sequences of the COI gene in the DNA of the worms from the mixed colony and their offspring confirmed species identity. In conclusion, species-specific coelomocyte-derived markers may be a useful complement to morphological and DNA-based taxonomy during studies on syntopic earthworms.