Volumetric Changes Research Articles

Brain volume loss after cranial irradiation: a controlled comparison study between photon vs proton radiotherapy for WHO grade 2-3 gliomas.

Radiation therapy (RT) is an integral treatment component in patients with glioma but associated with neurotoxicity. Proton RT (PRT), as compared with photon RT (XRT), reduces excess radiation to nontarget tissue. We used a retrospective method to evaluate brain imaging metrics of neurotoxicity after treatment with PRT and XRT for glioma. We analyzed brain volume change in thirty-four patients with WHO grade 2-3 gliomas treated with either PRT (n = 17) or XRT (n = 17). Both groups were carefully matched by demographic/clinical criteria and assessed longitudinally for two years post-radiotherapy. Brain volume change was measured as ventricular volume expansion in the tumor free hemisphere (contralateral to RT target) as a proxy indicator of brain volume loss. We further assessed the impact of volumetric changes on cognition in PRT patients, who completed neuropsychological testing as part of an outcome study. We found significant ventricular volume increases in the contralesional hemisphere in both groups at two years post-RT (F(1, 31) = 18.45, p < 0.000, partial η2 = 0.373), with greater volume change observed in XRT (26.55%) vs. PRT (12.03%) (M = 12.03%, SD = 16.26; F(1,31) = 4.26, p = 0.048, partial η2 = 0.121). Although, there was no group-level change on any cognitive test in PRT treated patients, individual changes on cognitive screening, working memory, processing speed and visual memory tasks correlated with contralesional brain volume loss. This study suggests progressive brain volume loss following cranial irradiation, with greater severity after XRT vs. PRT. Radiation-induced brain volume loss appears to be associated with measurable cognitive changes on an individual level. Prospective studies are warranted to validate these findings and their impacts on long-term cognitive function and quality of life. An improved understanding of the structural and functional consequences of cranial radiation is essential to develop neuroprotective strategies.

Mechanically Robust Polyimide Binder Realizes Stable and High Electrochemical Performance for Micro-Silicon Anodes in Lithium-Ion Batteries.

Silicon is regarded as a highly promising anode material for lithium-ion batteries, attributed to its substantial theoretical specific capacity. The practical implementation of Si-anodes is hindered by side reactions and significant volumetric changes, ~300% to 400%, occurring during the lithiation/delithiation processes. Pertinent binders can effectively mitigate the stress resulting from the volumetric exchange in Si-anodes. Herein, we developed a mechanically stable polyimide binder PI-CF3 and introduced trifluoromethyl and hydroxyl groups for commercial microparticular Si-anodes. With the highest Young's modulus of ~921.1 MPa, the binder presented the maximum resilience during the charging and discharging of Micro-Si, integrating the morphology, and reducing the degree to which the electrode disrupted ion and electric pathways. Moreover, -OH and -CF3 groups of the binder could potentially interact with the oxide layer at the surface of silicon through H-bonds resulting in a cross-linking network to improve interface stability. The as-prepared PI-CF3 binder with excellent intrinsic mechanical and electro-rich groups stabilizes the electrode structure and facilitates fast Li+ transportation. Consequently, at 0.6 Ag-1, the micro-Si anode produced an initial specific capacity of 1838 mAh g-1 at Si 0.66 mg cm-2. Besides, at Si 0.78 mg cm-2 specific capacity retained around 1219 mAh g-1 over 330 cycles.

Dynamics of choroid plexus volume is associated with the presence and development of fatigue in multiple sclerosis

BackgroundImmune-mediated processes are implicated in the pathogenesis of fatigue, a common symptom in multiple sclerosis (MS). The choroid plexus (CP) regulates central nervous system (CNS) immune homeostasis and undergoes volumetric...

Spiral volumetric optoacoustic tomography of reduced oxygen saturation in the spinal cord of M83 mouse model of Parkinson's disease.

Metabolism and bioenergetics in the central nervous system play important roles in the pathophysiology of Parkinson's disease (PD). Here, we employed a multimodal imaging approach to assess oxygenation changes in the spinal cord of the transgenic M83 murine model of PD overexpressing the mutated A53T alpha-synuclein form in comparison with non-transgenic littermates. In vivo spiral volumetric optoacoustic tomography (SVOT) was performed to assess oxygen saturation (sO2) in the spinal cords of M83 mice and non-transgenic littermates. Ex vivo high-field T1-weighted (T1w) magnetic resonance imaging (MRI) at 9.4T was used to assess volumetric alterations in the spinal cord. 3D SVOT analysis and deep learning-based automatic segmentation of T1w MRI data for the mouse spinal cord were developed for quantification. Immunostaining for phosphorylated alpha-synuclein (pS129 α-syn), as well as vascular organization (CD31 and GLUT1), was performed after MRI scan. In vivo SVOT imaging revealed a lower sO2SVOT in the spinal cord of M83 mice compared to non-transgenic littermates at sub-100μm spatial resolution. Ex vivo MRI-assisted by in-house developed deep learning-based automatic segmentation (validated by manual analysis) revealed no volumetric atrophy in the spinal cord of M83 mice compared to non-transgenic littermates at 50μm spatial resolution. The vascular network was not impaired in the spinal cord of M83 mice in the presence of pS129 α-syn accumulation. We developed tools for deep-learning-based analysis for the segmentation of mouse spinal cord structural MRI data, and volumetric analysis of sO2SVOT data. We demonstrated non-invasive high-resolution imaging of reduced sO2SVOT in the absence of volumetric structural changes in the spinal cord of PD M83 mouse model.

Effects of thermal cycles and time-dependent behavior of the deck on steel network arch bridges

Network arches are a type of arch bridges with inclined hangers, in which some hangers cross each other at least twice. This paper aims to evaluate the effects of thermal fluctuations and volumetric changes of the concrete deck on steel network arches. Fifty-nine variants of a reference network arch bridge were developed, assuming identical arch geometries but varying hanger arrangements. Each bridge was modeled using the finite element method and subjected to heat flux due to solar radiation and changes in ambient temperature in addition to heat transfer via conduction, convection, and radiation. The time-dependent deformations of the concrete deck were implemented using a rate-type formulation. Results obtained during a one-year period after the assumed end of construction showed that stress changes in the arch bridge due to ambient and time-dependent effects were not very sensitive to the hanger layout. Neglecting concrete creep and shrinkage was found to cause a 15-20% underestimation of maximum stresses in the concrete deck, whereas a 40-60% error was observed in both the deck and rib when thermal effects were ignored. The radial arrangement of hangers, already known to perform favorably under live loads, was also found to provide the smallest bending moments and the fewest number of relaxed hangers due to thermal and time-dependent effects.

Regional changes in the free Achilles tendon volume in response to repeated submaximal contractions

IntroductionThe Achilles tendon (AT) may become smaller in volume following acute bouts of heavy and sustained loading likely because of transient fluid exudation to the periphery and this could augment cellular mechanotransduction and tendon adaptation. Given the structure of the AT is distinct across its length, regional changes in the free AT volume may occur in response to loading. This study aimed to investigate whether the change in tendon volume in response to repeated submaximal loading is distinct across the free AT length. MethodsSixteen ATs of healthy males and females (age 24.4 ± 9.4 years, body mass 70.9 ± 16.1 kg, height 1.7 ± 0.1 m) were scanned at rest using freehand 3D ultrasound. Scanning was done before and immediately after submaximal (75 %) voluntary isometric plantarflexion contractions (8 s) involving four sets of ten repetitions. Regional volumetric changes were assessed across the free AT length by dividing the tendon into distal, mid, and proximal regions. ResultsSignificant reduction in the free AT volume occurred across all tendon regions in response to the intervention, however, the mid- region exhibited the greatest reduction in volume compared to the proximal region (P = 0.025). DiscussionThe fact that volume reduction was greatest in the mid-region compared to the proximal region of the free AT may suggest greater tendon adaptation, via mechanotransduction pathways, in the mid-region and this may be important for tendon health and injury prevention.

Gray matter volumetric changes in tinnitus: The impact of hearing loss and severity

Tinnitus is a phantom auditory sensation that commonly co-occurs with hearing loss. Both tinnitus and hearing loss can impact the quality of life, emotional well-being, and cognitive functioning of the affected individuals. While previous studies have highlighted structural alterations in hearing loss and/or tinnitus, the fundamental neural mechanisms underpinning tinnitus severity remain poorly understood. In this study, we conducted a voxel-based morphometry to investigate gray matter (GM) volume differences among groups of participants with varying tinnitus severity and hearing status, and controls within a large sample. We observed reduced GM volume in the left anterior insula and right planum polare in participants with hearing loss, regardless of their tinnitus status, compared to normal hearing controls. We noted decreased GM volume in the bilateral anterior and posterior insula for those with tinnitus and normal hearing compared to a normal hearing control group. Further, the tinnitus with hearing loss group showed decreased GM volume in the left planum polare, left inferior temporal gyrus, bilateral anterior temporal gyri, and right superior frontal gyrus compared to the normal hearing control group, suggesting a combined effect of hearing loss and tinnitus. While tinnitus severity did not show a significant overall effect, there was a significant positive correlation between tinnitus distress and GM volume in bilateral planum polare. Our findings enhance the understanding of structural brain changes related to hearing loss and tinnitus, and advance the overall knowledge of tinnitus pathophysiology, which can contribute to the development of more effective treatments for tinnitus.

Monitoring seismic velocity changes at Campi Flegrei (Italy) using seismic noise interferometry

Campi Flegrei is a volcanic field located west of Naples (Italy) in a densely populated area. Since 2005, its ground has been rising steadily due to the accumulation of fluids at shallow depths. The inflation of volcanic edifices is a possible precursor of an impending eruption. The uplift is accompanied by increasing seismic activity. This raises concerns about the possibility that the volcano may be on the verge of an eruption. To track the fluid movement, it is possible to monitor subtle changes of velocities of seismic waves by exploring ambient seismic noise. By examining different frequency bands, we can observe velocity changes at different depths. We interpret these changes as a monitoring of depth-dependent deformation in addition to the standard monitoring of surface deformation. We observe a velocity decrease in the long-term trend, presumably due to the extension of the hydrothermal system at shallow depths. To explain the long-term changes, we model a spherical pressure source to simulate volumetric strain changes induced by recent fluid activity. The model explains both, surface and subsurface deformation which leads to the opening of microcracks and pores, resulting in the observed velocity decrease. The short-term velocity changes are mainly driven by temperature or groundwater level changes. Once velocity changes are corrected for seasonal effects, remaining short term velocity changes can be associated with volcanic activity and earthquake swarms.

Automated multiple sclerosis progression rate computation of a patient from 2D FLAIR images with Rayleigh-Weibull-Fuzzy imaging and augmented morphing method

Multiple sclerosis (MS) is a neurological demyelinating disorder affecting brain and spinal cord by attacking the myelin sheaths of nerves. Estimation of the volumetric changes in MS lesions is a challenging and specialized task which is executed and judged by medical experts. The change in the volume of the lesions provides crucial information on MS progression or regression by comparing the magnetic resonance images (MRI) taken in successive scans. However, visual comparison of the images, even with an expert eye, would not always lead to a conclusive decision nor a consensus on progression or regression. Therefore, we present an automated expert system for estimating MS progression rate by automatic lesion segmentation and volume estimation using two-dimensional MRIs, which is also adaptable to various parameters, slice thickness and increment. A clinical dataset is specially formed for this research which contains three sets of 135 MR images of an MS patient generated within approximately 23- and 6-month periods consecutively with identical device parameters. The lesions are segmented by a novel Rayleigh-Weibull-Fuzzy (RWF) imaging method based on the Nakagami distribution and specialized fuzzy 2-means. Subsequently, the segmentation module is trained to fit the ground truths images created by experts to achieve the highest dice score possible for a total number of 56 images containing lesions, which is found as 93.76%. Afterwards, several imaginary image sequences are generated by augmented linear and nonlinear morphing for re-segmentation of imaginary lesions by RWF. Finally, we estimated the volumetric change between the first two MRI sequences to adjust the morphing module and to predict the progression rate of the lesions in time. The framework automatically selected the highest accuracy, which is 99.9% in the training session and estimated the progression rate in the testing phase with 99.69% accuracy, which are not achievable without augmented morphing methodology. For the first time in the literature, an automated framework could estimate the MS progression rate from the raw MR images, which is also the main innovation of this paper and the outputs would be beneficial for the experts working on this field.

Hollow porous Co0.85Se/MoSe2@MXene heterostructured anode for sodium-ion hybrid capacitors

Metal selenides have garnered significant attention as promising anode materials for sodium-ion hybrid capacitors (SIHCs), yet its sluggish reaction kinetics as the battery-type anodes pose a challenge for developing high power SIHCs when coupled with capacitor-type cathodes. To overcome this limitation, constructing heterostructured metal selenides anodes has emerged as a promising strategy to balance the reaction kinetics between two different types of electrodes. Herein, the hollow porous TA-Co0.85Se/MoSe2@MXene anode with multiple heterostructures for sodium storage has been engineered via facile double-etching and self-assembly approach. The well-tailored void space and abundant heterointerfaces may effectively mitigate volumetric changes and enhance structural stability. Density functional theory (DFT) calculations further reveal that the local multilevel built-in electric fields induced by the heterointerfaces can effectively accelerate charge transfer and reduce the migration energy barrier of Na+, thus boosting the reaction kinetics. The fabricated anode demonstrates superior long-term cycling performance with a reversible capacity of 414 mA h/g after 1000 cycles at 1 A/g and remarkable rate capability of 425 mA h/g at 5 A/g. Benefiting from the ingenious structure and excellent sodium storage performance, the as-built SIHCs achieves an impressive energy density of 193 W h kg−1 and high power output of 18 kW kg−1 with outstanding capacitance retention of 90 % at 2 A/g after 10,000 cycles. This study provides valuable insights into the rational design of multiple heterostructured anode materials with multilevel built-in electric fields for high-performance SIHCs.

Undrained shear mechanical behaviors of dense gassy sand

Shallow gas can cause many disasters, and it is reported in many marine engineering constructions. For this, it is imperative to understand the impact of gas on the mechanical behaviors of soil. This study investigated the influence of undrained triaxial compression tests on dense gassy sand commonly encountered in coastal areas. Triaxial tests were performed on specimens with saturations of 100%, 99.8%, 95.9%, and 92.7% under confining pressures of 50 kPa and 200 kPa by a self-developed multi-purpose integrated triaxial apparatus (MITA) for gassy soil. The results are presented in terms of monotonic stress‒strain behavior, volumetric behavior, shear strength, and excess pore water pressure (EPWP). The occurrence of gas bubbles has different effects on loose and dense sands, augmenting the undrained shear strength of loose sand while concurrently diminishing that of dense sand. The deviatoric stress of dense sand increases during shear shrinkage, which is similar to the characteristics of loose sand under the influence of gas bubbles. However, following sand dilation, the effect of gas bubbles on deviatoric stress manifests in an antithetical manner. With elevated gas content, the shear strength of dense sand decreases, accompanied by a deceleration in the development of EPWP and a notable increase in volumetric changes. To this end, a microscopic explanation concerning the deformation and evolution of gas bubbles within sand during the shear process was presented to reveal the macroscopic laws governing the undrained shear attributes of dense gassy sand.

Enhanced strain mapping Unveils internal deformation dynamics in Silicon-based lithium-ion batteries during electrochemical cycling

Silicon-based anodes have emerged as a promising advancement in lithium-ion battery technology, offering significantly higher lithium storage capacities than traditional graphite. However, the volumetric expansion of silicon—anodes can swell by up to 300 % during lithiation—presents serious challenges to their structural integrity and electrochemical stability. This study investigates the internal structural dynamics of silicon anodes during lithiation and delithiation cycles. A novel cell design for a 18,650 cylindrical cell featuring micro-sized internal speckles within the silicon anode is presented. This design improves the simulation of electrochemical conditions and allows for precise displacement tracking, mitigating impacts on capacity and cycle performance while enhancing Digital Volume Correlation (DVC) analysis. The research prioritizes reducing scan time and radiation exposure in micro-CT assessments of Li-ion cells, and improves the accuracy of internal strain mapping via DVC. Displacement fields over three charging and discharging cycles are documented. Notably, uneven volumetric changes are observed, with local displacements reaching up to 35 µm in areas smaller than 2.5 mm in radius, which contracted during charging and expanded during discharging. This protocol offers insights into the relationship between electrode mechanics and cell performance, promoting non-destructive evaluations of internal structures in commercial cells.

Mandibular asymmetry. Hemimandibular hyperplasia vs. hemimandiubular elongation

Introduction. Hemimandibular hyperplasia and elongation create a developmental asymmetry characterized by volumetric changes of the hemimandible. Both entities cause progressive aesthetic and functional problems causing depression with poor quality of life. The treatment of these anomalies is combined, orthodontic and surgical Material and methods. The study was based on the analysis of bibliographic sources as well as the rehabilitation of two patients diagnosed with hemimandibular hyperplasia and hemimandibular elongation. Results. The specialized literature proposes a variety of surgical techniques for osteotomy of the mandible to correct mandibular asymmetries. The surgical planning of the interventions was carried out using the digital protocol, with the manufacture of intermediate and final splints. Conclusions. Contemporary digital medical imaging in combination with virtual surgical planning allows a patient specific treatment protocol, a fact that significantly contributes to optimizing not only the treatment plan but also the surgery itself.

Successful Factors for Improving Aortic Remodeling with Thoracic Endovascular Repair and Bare Stent Extension

ObjectiveProximal ExTension to Induce COmplete ATtachment (PETTICOAT), which utilizes downstream bare metal stents for structural support, demonstrates potential, yet its adoption is limited by variable outcomes. This study elucidates the potential of PETTICOAT in aortic dissection, emphasizing the determinants that guide patient selection. MethodsA retrospective analysis of 60 patients who underwent full PETTICOAT for aortic dissections was conducted. A multivariate logistic regression model identified predictors of favorable aortic remodeling. Patients underwent standardized follow-up with CT scans to assess size, volumetric changes, and anatomical conditions. Selection criteria included full PETTICOAT application and a minimum three-month follow-up. Demographics, preoperative conditions, and procedural details were collected and analyzed. ResultsThe analysis identified predictors of favorable aortic remodeling, including age over 60, a larger downstream aorta stent graft, a smaller abdominal aorta (<450mm2), and oral angiotensin II receptor blocker (ARB) administration. Over a median 47.5-month follow-up, survival rates in the favorable remodeling (97.3%) and unfavorable groups (100%) were similar. Downstream aortic event-free survival rates did not significantly differ (89.2% vs. 73.9%), although the unfavorable group had a relatively higher incidence of distal stent-induced new entries (26.1% vs. 8.1%). ConclusionsThe PETTICOAT concept effectively enhances aortic remodeling in complex aortic dissections. Predictors for favorable remodeling, including age, stent graft sizing, aortic diameter, and ARB therapy, offer insights for optimizing patient selection. This approach improves survival outcomes, mitigates risks associated with untreated aortic segments, and provides a minimally invasive solution for aortic dissections. Despite some outcome variations, the technique holds promise for addressing the challenges of aortic dissections, with the potential for further refinement in patient selection and technique application.

Assessing abdominal aortic aneurysm growth using radiomic features of perivascular adipose tissue after endovascular repair

ObjectivesThe study aimed to investigate the relationship between the radiomic features of perivascular adipose tissue (PVAT) and abdominal aortic aneurysm (AAA) growth after endovascular aneurysm repair (EVAR).MethodsPatients with sub-renal AAA who underwent regular follow-up after EVAR between March 2014 and March 2024 were retrospectively collected. Two radiologists segmented aneurysms and PVAT. Patients were categorised into growing and non-growing groups based on volumetric changes observed in two follow-up computed tomography examinations. One hundred seven radiomic features were automatically extracted from the PVAT region. Univariable and multivariable logistic regression was performed to analyse radiomic features and clinical characteristics. Furthermore, the performance of the integrated clinico-radiological model was compared with models using only radiomic features or clinical characteristics separately.ResultsA total of 79 patients (68 ± 9 years, 89% men) were enroled in this study, 19 of whom had a growing aneurysm. Compared to the non-growing group, PVAT of growing AAA showed a higher surface area to volume ratio (non-growing vs growing, 0.63 vs 0.70, p = 0.04), and a trend of low dependence and high dispersion manifested by texture features (p < 0.05). The area under the curve of the integrated clinico-radiological model was 0.78 (95% confidence intervals 0.65–0.91), with a specificity of 87%. The integrated model outperformed models using only radiomic or clinical features separately (0.78 vs 0.69 vs 0.69).ConclusionsHigher surface area to volume ratio and more heterogeneous texture presentation of PVAT were associated with aneurysm dilation after EVAR. Radiomic features of PVAT have the potential to predict AAA progression.Clinical relevance statementRadiomic features of PVAT are associated with AAA progression and can be an independent risk factor for aneurysm dilatation to assist clinicians in postoperative patient surveillance and management.Key PointsAfter EVAR for AAA, patients require monitoring for progression.PVAT surrounding growing AAA after EVAR exhibits a more heterogeneous texture.Integrating PVAT-related features and clinical features results in better predictive performance.Graphical

Volumetric Changes of Frontal Sinus after Correction of Anterior Open Bite

Volumetric Changes of Frontal Sinus after Correction of Anterior Open Bite

Ultra-Low Alginate-Based Multifunctional Composite Binders for Enhanced Mechanical, Electrochemical, and Thermal Performance of Li-S Batteries.

The practical application of Li-S batteries, which hold great potential as energy storage devices, is impeded by various challenges, such as capacity degradation caused volume change, polysulfide shuttling, poor electrode kinetics, and safety concerns. Binder plays a crucial role in suppressing volume change of cathode side, thereby enhancing the electrochemical performance of Li-S batteries. In this research, a novel network binder (SA-Co-PEDOT) composed of sodium alginate is presented, Co2+ ions as cross-linking agent and PEDOT as an electronic conductor. The theoretical analysis and experimental testing confirm that the SA-Co-PEDOT binder with synergistic combination of catalytic center and electron transfer network effectively mitigates large volumetric changes during cycling while simultaneously enhancing electrode kinetics through controlling the deposition morphology of sulfur end product and its nucleation and dissolution. As a result, it achieves a capacity of 844 mAh g-1 after 150 cycles at 0.2 C. Moreover, the electrode with SA-Co-PEDOT binder subjected a bending test maintains a capacity of 395 mAh g-1 after 500 cycles at 0.5 C, exhibiting an impressively low decay rate of only 0.11%. Even with an ultra-low content of 2 wt.% SA-Co-PEDOT binder, the electrode still maintains a capacity of 999.7 mAh g-1 after 100 cycles at 0.5 C.

Utilizing rice husk-derived Si/C composites to enhance energy capacity and cycle sustainability of lithium-ion batteries

Traditional graphite anodes have a specific capacity of approximately 372 mAh/g, whereas silicon presents a promising alternative with theoretical capacities reaching up to 4200 mAh/g. However, substantial volumetric changes in silicon during lithiation lead to rapid degradation of capacitance. This study explores the utilization of rice husk, an abundant agricultural waste, as a raw material for Si/C composites. Rice husk inherently contains significant amounts of silicon and carbon, rendering it a sustainable and economical source. The activated carbon was derived from rice husk by carbonization and thermochemically activation with activation temperature of 850 °C and KOH agent. The silicon dioxide was derived from rice husk by subjecting to annealing in a muffle furnace at 650 °C for 4 h following NaOH and HCl solution treatment. The silicon was derived from silicon dioxide by thermomagnesium treatment in a tube furnace at 700 °C for 120 min. SEM, elemental analysis, XRD, Raman, and FT-IR were used to characterize the materials to evaluate their morphological and structural composition. Electrochemical performance evaluation demonstrated improved energy capacity and stability, highlighting rice husk-derived Si/C composites as a viable solution for advancing lithium-ion battery performance. This innovative approach not only lowers production costs but also supports sustainable development by effectively utilizing agricultural waste.

The Effect of Hydrate Formation Conditions on the Mechanics of Laboratory Methane Hydrate‐Bearing Sediments

AbstractThe mechanics of methane hydrate‐bearing sediments (MHBS) have been broadly investigated over recent years in the context of methane‐gas production or climate‐change effects. Their mechanical investigation has mainly been carried out using models constructed from experimental data obtained for laboratory‐formed MHBS. Along with the dominant effects of hydrate saturation and morphology within the host soil pores, this study recognizes the effective pressure at which the hydrate is formed as a key factor in the MHBS mechanics. A state‐of‐the‐art experimental study has been conducted in order to isolate the effect of the hydrate formation pressure, for use as a model parameter. Two generalized mechanical prediction models that incorporate the effect of the hydrate formation pressure are developed in this work: (a) an analytical shear strength prediction, and (b) an empiric graphical model for predicting volumetric changes along a given stress path. The models are related to a novel data representation which enables the analysis of a few individual test outcomes as a whole, through a volume‐change mapping that describes the complex influence of the volumetric effect of hydrate in MHBS, under combined hydrostatic and deviatoric loading scenarios. In this study, we delve into a specific configuration of hydrate morphology, hydrate saturation, and host soil type, enabling a distinctive fundamental geotechnical investigation and the development of a conceptual modeling approach. The paper describes the approaches by which the MHBS properties can be extracted for other MHBS samples (than those examined in this work) having different host soils and hydrate pore‐space morphologies.

Comparative Analysis of Foundation Systems in Expansive Soil: A Three-Dimensional Model Approach to Moisture Diffusion and Volume Changes

AbstractThis study compares the performance of various foundation systems in expansive soils, such as mats, granular anchor piles, and concrete piles. Expansive soils experience volumetric changes due to moisture fluctuations, which can lead to structural damage. Abaqus software, in conjunction with the SCV approach, is used to analyze soil-foundation interactions. A custom subroutine enhances simulation accuracy by incorporating empirical data on unsaturated clay behavior, matric suction, and variations in effective stress. The method’s accuracy is validated by comparing simulation results to field and laboratory experiments. The findings indicate that increasing the applied load on mats decreases overall heave but increases the differential heave. Additionally, higher soil permeability dereases the differential heave of mats. Granular anchor piles outperform concrete piles by more than 50% in highly expansive soils, suggesting a preference for these foundations. This study provides insights into the behavior of expansive soils, which will assist engineers in designing resilient foundation systems for structures.