Fill Site Research Articles

Soft soil foundation treatment of hydraulic fill site based on vibration boosting drainage consolidation method

Reclamation from the sea is a method of expanding urban area, but it also faces the problem of difficult treatment of soft soil foundation by hydraulic reclamation. Therefore, a soft soil consolidation method that combines vibration pressure boosting drainage and piled-load static pressure stacking is now proposed. To verify the effectiveness of this method, a consolidation test based on soft soil samples was designed and conducted in the study. The test results showed that when the sampling height was 240mm, the overall moisture content of the consolidated soil sample was the highest, 44.3%, and the consolidation effect was the worst. When the sampling height was 140mm, the overall moisture content obtained from the test was the lowest, 43.1%, and the consolidation effect was the best. The displacement of corner 2 and center point at the intersection of the preceding and following periods was greater, with values of 37.1 mm and 39.2 mm, respectively. At this point, the displacement of corner 1 was significantly smaller, at 30.9 mm. In the later loading stage, the slope of the vertical displacement curve significantly increased. When the experimental time reached 7000 min, the mixed method designed in this study had a drainage rate of 0.53 ml/min, which was significantly higher than other traditional methods. The experiment outcomes indicated that the method designed in this study had certain application potential for improving the consolidation effect of soft soil foundation in hydraulic fill sites.

A new one-dimensional consolidation creep model for clays

Creep deformation is a prevalent form of deformation infill projects, and accurately characterizing the creep of fill soils is essential for ensuring the safe and reliable operation of these projects. To develop a novel variable-order fractional creep model that describes the consolidation creep behavior of fill soils, this research enhances the fractional order algorithm to achieve more precise fractional orders and determine the variable order function. Consequently, a novel variable-order fractional element featuring viscoelastic memory effects is introduced and formulated as a model. Unlike the traditional Maxwell model, the new model is simpler, has fewer parameters, and includes a memory effect that reveals the characteristics of mechanical properties over time during the creep process. In addition, this study validates the proposed model's applicability and modeling benefits through one-dimensional consolidation creep tests on red clay at the fill site. The findings indicated that the change in fractional order in the new model should be an exponential function. The trend of decreasing fractional order with time is consistent with the soil consolidation creep-hardening behavior, suggesting that the variable fractional order function represents the changing nature of the soil. In this study, exploring fractional order laws reveals the physical significance of the fractional order element and enables the composed model to make effective predictions of relevant working conditions.

Monitoring Water and Soil Salinity across Mentor Marsh to Investigate Their Temporal and Spatial Variability

In this study, the surface water salinity of Mentor Marsh, located in Northern Ohio, USA, was monitored for 3 years by establishing 10 monitoring stations, whereas sporadic surface water salinity data were recorded at more than 30 locations in the marsh for 5 years. In addition, eight additional monitoring stations were established for recording the soil salinity at various temporal scales, whereas spatially distributed soil salinity was measured across the marsh in more than 500 locations to develop the salinity mapping in the soil using the Kriging-Gaussian method. Our analysis suggested that the water salinity in the winter was generally higher than in the summer. While the majority of the sites reported higher soil salinity characterized by high variability during the winter season, some sites reported a higher soil salinity in summer with less variability. The analysis revealed that the salt used on the road for the deicing purpose during the snowfall period was the primary reason for the increase in the salinity concentration in water in the western basin of Mentor Marsh, whereas the salt fill sites and brine well were primarily responsible for the higher salinity concentration in the eastern basin. Also, the drainage from the Morton Salt Company was a contributing factor to the sudden spike in some of the stations of the eastern basin. Both the surface water and soil salinity were relatively higher in the eastern basin than in the western basin. Apparently, salinity from the brine well field and salt fill sites seem to be more considerable than the road salt.

A quantum register using collective excitations in a Bose-Einstein condensate

A qubit made up of an ensemble of atoms is attractive due to its resistance to atom losses. In this work, we consider an experimentally feasible protocol to coherently load a spin-dependent optical lattice from a spatially overlapping Bose-Einstein condensate. Identifying each lattice site as a qubit, with an empty or filled site as the qubit basis, we discuss how high-fidelity single-qubit operations, two-qubit gates between arbitrary pairs of qubits, and nondestructive measurements could be performed. In this setup, the effect of atom losses has been mitigated, the atoms never need to be removed from the ground state manifold, and separate storage and computational bases for the qubits are not required, all of which can be significant sources of decoherence in many other types of atomic qubits.

Hwiccewyrm trispiculum gen. et sp. nov., a new leptopleuronine procolophonid from the Late Triassic of southwest England.

The fissure fill localities of southwest England and South Wales are well-known for preserving rich assemblages of predominantly small-bodied Late Triassic to Early Jurassic tetrapods, but many aspects of these assemblages remain contentious. The age of the Late Triassic fissures is disputed, with some lines of argument suggesting a latest Triassic (Rhaetian) age, whereas other evidence suggests they may be as old as Carnian. The fissures have been hypothesized by some workers to have formed on an archipelago, with island effects invoked to explain aspects of the assemblages such as the abundance of small-bodied species. Procolophonids were a successful group of Triassic parareptiles, best known from Early to early Late Triassic assemblages, but have only recently been described from one of the fissure fill sites (Ruthin) based upon fragmentary remains. Here, we describe new procolophonid specimens from another fissure (Cromhall) that represent at least six individuals of different sizes, with much of the skeleton represented including well-preserved skull material. The Cromhall procolophonid shows strong similarities to Late Triassic procolophonids from Scotland, Brazil and North America, but both autapomorphies and a unique character combination demonstrate that it represents a new species, which we name as Hwiccewyrm trispiculum gen. et sp. nov. Phylogenetic analysis places Hwiccewyrm in a derived clade within Leptopleuroninae, together with Leptopleuron, Hypsognathus, and Soturnia. The largest specimens of Hwiccewyrm demonstrate a body size that is similar to Leptopleuron and Hypsognathus, supporting other recent work that has questioned the insular dwarfism hypothesis for the fissure fill assemblages.

MONITORING AND ALERTING OF HAZARDOUS GASES IN MUNICIPAL SOLID WASTE USING MACHINE LEARNING TECHNIQUE

Abstract-In recent times, the rate of urbanization is proliferating; thus, there is a need to find a sustainable way for an urban development plan. There is rapid growth in the concept of smart cities all around the globe. A smart city is always incomplete without a smart waste monitoring structure that can manage the waste collection of the entire city. This paper proposes a Forest Fire alerting system, which keeps track of the hazardous gases produced by dumped waste by integrating a network of gas sensors. Land fill sites collect tons of municipal solid waste (MSW) using an open dump mechanism, causing gases to emerge, which may cause disease and the greenhouse effect. Mainly, landfill environments are observed using a portable system that does not continuously monitor and measure emitted gas levels. It is also difficult to evaluate changes in landfill emissions over the long term unless they are monitored at regular intervals according to a detailed plan. This paper presents a new monitoring method to measure gas levels in landfill sites, which documents dynamic changes in gas composition concentrations over the long term. The system was placed in the middle area of the landfill and was charged using solar panels for convenience and greater efficiency during monitoring.

Flood fatalities in eastern Kentucky and the public health legacy of mountaintop removal coal mining

ABSTRACT Heavy rains at night caused severe flooding in eastern Kentucky on 28 July 2022, resulting in 39 deaths. Using publicly available information, we assembled a database of these fatalities, including demographic characteristics and location of death. We perturbed fatality locations and plotted them on a topographical map highlighting mountaintop removal mining with valley fill sites, where mountaintops were excavated to mine thin seams of coal. This map reveals many flood fatalities occurred along rivers or streams near such sites. Previous research suggests that surface mining has contributed to the majority of land cover change in this region, and this has increased storm water runoff. The legacy of coal mining in Central Appalachia could thus present immediate challenges to public health and safety beyond more frequently studied health outcomes associated with occupational and environmental exposures. A review of prior surface mining legislation to assess its effectiveness is warranted.

First afrosoricid out of Africa: an example of Pliocene ‘tourism’ in Europe

The afrosoricids are an endemic order exclusively from Africa with a very scarce fossil record. In this work, we present the first record outside this continent. The “otter shrew” Europotamogale melkarti n. gen. n. sp. was found in the Moreda 3 karstic fill site in Granada (Spain), of MN15 age (mid-Pliocene). This new taxon confirms the semiaquatic faunal interchange between Europe and Africa. We hypothesize that this tenrecid, representative of a family frequently present in the Central African faunas, migrated to the north of the continent via the Sahabi river system that connected North and Central Africa. Europotamogale n. gen. is the first known afrosoricid that migrated between the two continents. It was present in Europe for a very short time (as a ‘tourist genus’). To date, this phenomenon has only been described in genera of European origin, such as the pika Prolagus or the mouse Apodemus.

Factors Associated with Prevalence of Occupational Injuries among Workers in Informal Recycling Businesses at Kiteezi Landfill Wakiso District, Uganda

There is increasing global concern on the prevalence of occupational injuries among workers in informal recycling in developing countries and especially those in sub-sahara Africa. This is arising due partly to the poor methods of waste management. This was observed in the eastern African countries and in particular in Uganda. The study focused on the Kiteezi Land fill site in Wakiso District central Uganda, and investigated the prevalence of occupational injuries among workers in informal recycling businesses, the factors (individual and institutional) influencing the prevalence of these injuries and the association between these factors. The study employed quantitative research approach using a cross-sectional research design, and collected data from 112 participants who were selected by stratified sampling technique. This data was collected using structured questionnaire and was analyzed at univariate, bivariate and multivariate levels. The results show that the prevalence of occupational injuries was 55.4% and the only significant factor was accessibility to sanitation facilities (AOR= 0.38; 95%CI: 0.16-0.94, P = 0.05). There is therefore a high prevalence of occupational injuries among workers in this informal recycling unit which if not addressed will inevitably contribute to the increase of the disease burden in the country. This study therefore strongly recommends the need for not only education and awareness for the workers but also provision of all the essential personal protective equipment and processes and relevant accessible sanitary facilities.

Application of the Richards Model in Settlement Prediction of Loess-Filled Foundations

The Richards equation has high plasticity and compatibility. Compared with other curve equations, it has higher applicability and accuracy in describing S-shaped curves. It can describe the changes in the initial growth stage, rapid growth stage, and stable growth stage of organisms well and reflect the slow-fast-slow change characteristics of growth. In this paper, the Richards model is introduced into the settlement deformation prediction of loess-filled foundation. Taking a high-loess fill site in northern Shaanxi Province as an example, continuous settlement deformation monitoring is carried out for the filling during the project operation period, and the settlement characteristics of a loess-filled foundation are studied using the monitoring results. It is considered that the settlement deformation curve of a loess-filled foundation has similar characteristics; that is, its deformation increases slowly in the early stage, rapidly in the middle stage, and is basically stable at a fixed value in the later stage. Its cumulative deformation time history curve is a smooth S-shaped curve, and the cumulative settlement increases with time and tends to converge. Analysis shows that the time history curves of cumulative settlement, the settlement deformation rate, and the acceleration of loess foundation filling are highly consistent with the Richards model. Compared with the modified exponential model and hyperbolic model, the predicted results are closer to the measured results; that is, the Richards growth model can be used to predict the settlement deformation of a fill foundation.

Analytical model for donor like Gaussian traps in organic thin-film transistor

Structural defects and chemical impurities exist in organic semiconductors acting as trap centers for the excited states. This work presents a novel analytical model to calculate the trapping and detrapping rates between two Gaussian densities of states. Miller-Abrahams rate and Fermi-Dirac statistics are employed in this model. The introduction of effective filled and empty sites for correlated bands greatly simplifies the expression of recombination rate. A technology computer-aided design simulator was used to simulate the donor-like traps in an organic semiconductor DPP-DTT based thin-film transistor, showing excellent agreement with the measured subthreshold swing difference and residual surface charge in the transfer characteristics. • A new method to analyze the trapped charges between two Gaussian density of states in organic semiconductors. • Two variables are defined in the expression of detrapping rate to simplify the algorithm complexity. • This approach can be conveniently applied on the technology computer-aided design (TCAD) technology. • A good agreement with the measured transfer characteristic confirms the robustness of this approach.

Mathematical modelling of cross-linked polyacrylic-based hydrogels: physical properties and drug delivery

Recently, hydrogels have gained significant importance in different applications, such as tissue engineering and drug delivery. They are 3D structures of hydrophilic polymers held together through physical or chemical crosslinking. Important is their ability to swell in presence of solvents, forming elastic gels able to maintain their original shape. Furthermore, these scaffolds slowly degrade in the physiological environment, leading the growing tissue to replace the former filled site. In this work, hydrogels have been synthetized using branched polyacrylic acid (carbomer) cross-linked with an aliphatic polyetherdiamine (elastamine). In particular, we focused on the description of their equilibrium conditions in swollen state and the dynamic simulation of the swelling process. These hydrogels exhibited a peculiar swelling behaviour characterized by an overshoot of the volume increase before reaching the equilibrium. Notably, such behaviour was found at different pH values. In this manuscript, the swelling behaviour was studied by mathematical modelling. Moreover, the ability of these devices to release drugs was also examined through a literature model to understand the different operating transport mechanisms.

Experimental Study on Double Row Micropiles and Anchors Composite Retaining Structure in Deep Fill Site

In recent years, with the continuous advancement of urbanization in China and the gradual increase in the utilization scale of underground space, foundation pits may build in a narrow and compact environment. Meanwhile, miscellaneous fill layers in the city may cause construction difficulties when new foundation pits are excavated and supported. While we focus on the above problems, new retaining structure forms which are safe and economical are urgently needed. In this study, based on the excavation in a deep filling site in Jinan, the double row micropiles and anchors composite retaining structure is monitored under excavation, loading, and unloading conditions by installing sensors and testing. The stress and axial force distribution of the front and back row micropiles and anchors in the composite retaining system under different excavation depths and different loads are analyzed. The performance changes of the front and back row micropiles under different conditions and the contribution of anchors at different depths to the structure resistance during excavation and loading tests are discussed. The results show that double row steel piles and anchors composite retaining structure is feasible when excavating deep fill site in the urban area. In the composite retaining system, the stress of the front pile is greater than the back pile, the back pile has a lag when it starts working, and the axial force of the middle and upper anchor is greater than that of the bottom anchor.

Landfill Site Selection Using GIS and (AHP): Case Study of Ranya City

Ranya City is located in North West of Sulaymaniyah Governorate, Iraq. It has an area of (76.7) km2. In 2018, it was home for (102,571) inhabitants. Presently, there are no landfills in the study area that fulfills necessary environmental requirements; thus, informal and unsuitable solid waste dumping is negatively impacting human health and the environment. Land fill site selection can be a difficult task as it is impacted by different factors and regulations. This study is an attempt to identify and evaluate suitable landfill locations in the study area using Analytical Hierarchy Process (AHP) and Geographic Information System (GIS). Ten criteria are used in this process which includes: groundwater depth, surface water, residential areas, Geological formations, slope, elevation, soil type, land use, roads and archeological sites. AHP was used to determine the weight for each criteria using pairwise comparison matrix. Three classes of suitability index were found: unsuitable (98.47%), moderately suitable (0.003%) and suitable (1.52%) of the study area. Three suitable landfill sites were identified as candidate sites that meet the requirements with an area of (0.29) km2, (0.12) km2 and (0.098) km2 respectively.

Engineering characteristics of coral reef and site assessment of hydraulic reclamation in the South China Sea

Calcareous soil is a peculiar geotechnical medium which is utilized as land filler for engineering activities, such as the Maldives, Middle East, and South China Sea (SCS). Since the hydraulic dredged calcareous soil has a wide grain size distribution, irregular particle shape, crushable particles, high porosity, and poor uniformity, ground-improvement was conducted to improve the bearing capacity and reduce foundation settlement. In this paper, the geological conditions, material characteristics, and mechanical behavior of dredger fill site on a coral reef in the SCS were studied. The densification of soil using deep vibro-compaction combined with impact rolling was investigated. An innovative method of sprinkling water during impact rolling was put forward to improve rolling efficiency and soil compactness. A set of modified in-situ measurement and calculation methods suitable for the compactness of calcareous soil were put forward. Based on in-situ test results, the relationship between the soil bearing capacity and blow count of dynamic penetration test was established. It was suggested that the two-point parallel and arranged in equilateral triangles vibro-flotation method is effective for the reinforcement of hydraulic dredged calcareous soil, and after vibro-flotation, the loose soil on the ground surface should be compacted with a 25 kJ three-side impact roller for 20 passes and then compacted with 25 t smooth vibratory roller until there are no visible wheel tracks. In addition, the methods of ground improvement, in-situ test, and foundation evaluation were proposed to contribute to coral reef engineering designers. This paper also provides new insights for coral reef foundation filling and improvement around the world.

Monitoring ungauged watersheds for investigating the variability of flow and salinity to implement the possible removal of salt fill sites.

Salinity is a crucial environmental problem leading to profound consequences in wetland plants and aquatic habitats including the rapid development of Phragmites australis in the marshland. These Phragmites australis are extremely vulnerable to capture fire, which might eventually affect the overall ecosystem of the marsh. However, in order to restore the marsh, a hydrologic investigation is needed, which is possible if a watershed is gauged, and long-term data are available. In this study, a systematic approach has been presented to conduct hydrologic modeling and salinity prediction in an ungauged watershed in order to implement the possible removal of salt fill sites. The stage and electrical conductivity were measured continuously, whereas stream cross sections and velocity of the streamflow were recorded intermittently in the Blackbrook Creek to develop a rating curve and generate continuous streamflow data. The watershed model Soil and Water Assessment Tool (SWAT) was calibrated and validated to a monthly scale with good model performance. In the next step, critical sources of salinity were identified from the two tributaries in order to implement the removal of salt fill sites for the possible reduction of salinity in the marsh. While salinity loading was approximately 10 times higher from Marsh Creek (65.63tons to 2028.13tons per month) compared with Blackbrook Creek (10.23tons to 163.98 per month), the analysis suggested that salinity concentration was higher from Blackbrook Creek, which was particularly due to abandoned salt fill sites near the Creek. The salinity loadings were linearly correlated with streamflow on a monthly (R2 = 0.81) scale, which was utilized to generate the salinity loadings that were diverted due to the rerouting of the Creek through the new location in order to avoid salt fill sites and reduce salinity in the Mentor Marsh. Our analysis suggested that approximately 74kg/day salinity was being rerouted from the Marsh; however, the salt fill sites contribute salinity to the Marsh equivalent to 63kg/day, which still needs to be removed. The research findings are expected to be helpful for monitoring small ungauged watersheds.

Integration of GIS and fuzzy logic for land fill site selection

Integration of GIS and fuzzy logic for land fill site selection

The place of geoinformatics in waste management, sanitation and health risks prevention in Ado-odo/Ota local government area

Increasing population growth, lack of suitable waste treatment and disposal sites, in addition to inadequate equipment for waste recycling, poor town planning, accumulation of waste beside the roads and canals caused by inadequate waste collection and lack of enough data and information on waste generation could be observed as palpable causes of inadequate waste management in our societies, as well as sources of environmental pollution. This paper considered the applications of Geographic Information Systems in the selection of suitable land fill sites in Ado-Odo/Ota LGA. Geospatial data of the study area were obtained, buffer, overlay and intersection analysis were carried out to exclude non-suitable locations and identification of suitable sites. The suitable locations for landfill were selected, and we concluded that GIS is a veritable tool in qualitative decision making in environmental management and sustainable development.

DYNAMIC COMPACTION STUDY OF ELIMINATING THE COLLAPSIBILITY OF EOLIAN DEPOSIT FINE SAND

The eolian deposit fine sand in desert area has slight to severe collapsibility. Eliminating the collapsibility for the foundation soil of eolian deposit fine sand is a problem to be solved urgently in engineering. Combined with the engineering example, the dynamic compaction method is used to reinforce the foundation soil of eolian deposit fine sand. The effect and law of the dynamic compaction method to eliminate the collapsibility of the eolian deposit fine sand are evaluated with shallow plate loading test and laboratory soil test. The results show that the collapsibility of the eolian deposit fine sand is mainly affected by the moisture content and the density. The water content is especially prominent for the collapsible deformation. Before the dynamic compaction, the water content of the soil should be sufficient to make the soil moisture content reach the optimal water content. In the dynamic consolidation and reinforcement, the optimum hammer number in the filled site is 10 strike, and the optimum hammer number in the excavated site is 8 strike. The dynamic design of information construction(ie., the observational method) has to be used. After dynamic compaction, the bearing capacity of the eolian deposit fine sand is two times more than that before the dynamic compaction. In the collapsible test, the deformation increment of the eolian deposit fine sand is less with the time. The dynamic compaction method improves the collapsibility of the aeolian fine sand, among which the water is the main factor of controlling the collapsibility, and the dynamic compaction is the secondary factor. The research results help to provide reference for the design and construction of the foundation soil of eolian deposit fine sand by dynamic compaction, and provide reference for similar foundation treatment.

"Kaikki eivät halua kaatopaikkaa"

1960-luvulla Suomi kaupungistui nopeasti, mikä kasvatti jätteiden määrää niin kaupungeissa kuin kauppaloissakin. Uusien kaatopaikkojen löytyminen osoittautui vaikeaksi niin Helsingissä kuin myös Espoossa. Ratkaisuna jäteongelmaansa Espoon kauppala ehdotti Helsingille Laajalahden käyttämistä kaatopaikkana, minkä Helsinki hyväksyi asettaen erillisen komitean valmistelemaan uuden kaatopaikan perustamista lokakuussa 1963. Kaatopaikan perustaminen etenki kuitenkin hitaasti eikä sitä lopulta perustettu. Kaatopaikan suunnittelun aikana kuntien kaatopaikkapolitikkaa samoin kuin kaupunkisuunnittelukulttuuri muuttuivat merkittävästi. Myös luonnonsuojelun asema muuttui. Ympäristöhistorian alaan lukeutuva artikkeli tarkastelee kaatopaikasta käytyy keskusteluun osallistuneita toimijoita ja näiden näkemyksiä Laajalahdesta tarkastellen eri toimijoiden vaikutusta kaatopaikan suunnitteluun.