Bearing Capacity Research Articles

Assessment of Different Methods for Determinng Bearıng Capacıty for Shallow Foundatıon on Hill Slope

The bearing capacity of soil is a crucial factor in foundation design, and it can be determined using various methods such as IS 6403:1981, Meyerhof (1957), Hansen (1970), and Terzaghi (1943), among others. This paper aims to study the most suitable method for assessing the bearing capacity of soil in hilly regions like Aizawl, Mizoram. In this regard, the Durtlang locality which is the most developing area under the Aizawl Municipal Corporation (AMC) has been selected for the study area. The study involved collecting undisturbed soil samples from ten different locations of the study area which were then tested in the laboratory to determine their engineering properties. Based on the obtained soil properties, the safe bearing capacity (SBC) was calculated using different methods, including IS 6403:1981, Meyerhof (1957), Hansen (1970), and Terzaghi (1943). A comparative analysis was conducted to evaluate the SBC values derived from these methods. Moreover, a parametric analysis was also conducted to study the impact of cohesion 'c' and the angle of internal friction 'Φ’ of soil on the bearing capacity of soil. The study concluded that as the cohesion of the soil increased, the angle of internal friction tended to decrease. On the other hand, the safe bearing capacity (SBC) was found to increase with a higher angle of internal friction. The results of the comparative analysis revealed that, for the selected soil samples, the bearing capacities calculated using IS 6403:1981, Meyerhof (1957), and Terzaghi (1943) were higher than those derived from Hansen's (1970) equation. Notably, both Meyerhof (1957) and Hansen (1970) incorporate the slope angle in their bearing capacity calculations, whereas IS 6403:1981 and Terzaghi (1943) provide general formulas that do not account for slope effects. These findings highlight that the method chosen for calculating bearing capacity has a significant impact on the results.

Interpretation of geotechnical risk maps for Malatya province in terms of earthquake sequence on February 6, 2023

The earthquake sequence that occurred on February 6, 2023, centered in Türkiye caused extensive loss of life and significant damage. In this study, the geotechnical properties of the central districts of Malatya province, one of the provinces affected by these earthquakes, were calculated using data obtained. In the calculations, the correlations suggested by the Turkish Building Earthquake Code (TBEC) and internationally recommended correlations were used. Thus, the difference between the methods proposed by TBEC and internationally recommended correlations was interpreted. Using 1890 drilling data, 1765 seismic data, and 1764 microtremor data, calculations were made to determine bearing capacity values for 3 m x 3 m pad foundation, liquefaction potentials of the soil and soil classifications around this region. The results obtained from the calculations were mapped with geographical information systems-based software. Results of the study revealed that 2.9% of the study area in Battalgazi district and 1.71% for Yeşilyurt district had liquefaction potential. Almost 80% of each district was found to have a soil class of ZD (medium dense gravel and sand or clay layers) according to TBEC. The findings of the study were compared with previous studies, satellite images of the study area and post-earthquake observations. In areas where damage caused by the earthquake sequence was observed intensively, bearing capacity values were relatively low. It was concluded that building on poor soil conditions poses a profoundly serious risk in terms of earthquakes and very serious precautions should be taken by gathering several disciplines during the construction of these structures.

Lubrication and wear characteristics of bionic composite texture on friction pair under seawater condition

Abstract To improve the lubrication bearing capacity of the slipper pair of axial piston pump under seawater lubrication, a bionic composite texture (ball pit-ball convex) was designed based on the non-smooth surface structure of dung beetle, and friction and wear experiments were carried out with CF/PEEK and 316L stainless steel. Thirteen groups of experiments with different parameters and structure sizes were designed and studied. The surface morphology of materials under different structural sizes and test parameters were observed, and the lubrication and wear characteristics were analyzed. The results show that the cavitation effect can increase the total compressive capacity of the bionic composite texture by 51.2% and reduce the friction coefficient by 53.3%, and the diameter and area ratio of the ball pit have the most obvious influence on the bearing performance. It is also found that the bionic composite texture has better anti-friction performance than the single texture because it has the function of storing wear chips.

Effect of Axial Modification on the Meshing Performance of Involute Beveloid Gear Pair

In order to enhance the load-bearing capacity of the involute beveloid gear pair, this study proposes research on improving the contact stress through axial modification. Under the condition of segmented parabolic axial modification, the mathematical equation for the tooth flank of the beveloid gear is derived. A simulation meshing model for the beveloid gear pair is constructed to investigate the effects of different amounts and lengths of axial modification on the meshing performance, changes in flank and root stress, and transmission error before and after modification. The results indicate that as the modification amount increases, the maximum equivalent stress initially decreases and then exhibits a tendency towards stability. Moreover, an increase in modification length concentrates the contact zone towards the middle of the tooth flank while expanding the range of tooth root stress distribution, and it also leads to a decrease in maximum equivalent stress. The implementation of the modification has been observed to result in a reduction in cumulative transmission error and an effective reduction in edge load on the beveloid gear pair, which has been demonstrated to enhance the bearing capacity and transmission stability extension while also impacting the dynamic meshing performance.

Bending performance and design of reinforced concrete ribbed bridge deck slabs retrofitted with steel-plate reinforcement

ABSTRACT This study aimed to assess the bending performance and design of reinforced concrete ribbed bridge deck slabs with steel-plate reinforcement. Two reference members and three steel-plate reinforcements were designed for four-point bending loading tests, numerical simulations, and theoretical analyses. Steel-plate reinforcement improves the flexural load bearing capacity and stiffness of the bridge deck slab and effectively controls crack development, compared to old bridge reconstruction requirements. The bridge deck is best stressed when the bolt (M12 mm × 200 mm) spacing is 0.8 times the slab thickness. To prevent brittle damage to the bridge deck, a steel plate with a width of 160 mm and thickness of 10 mm should be used for strengthening. This aligns with engineering practice whereby the bolt shear capacity is used to assess the effectiveness of steel-plate reinforcement in bridge deck slabs. Bolt shear arrangement based on the slip effect and a sufficient increase in the diameter of the bolts at both ends of the steel plate are more appropriate for the bending effect of the bridge deck structure. The results provide a reference for the design of deck slab reinforcement for assembled ribbed bridges.

Research on the bearing performance of HSCA high-strength preloaded expansion piles in calcareous sand foundation

With the rapid development of infrastructure construction on oceanic reefs, calcareous sand, as the primary medium of these reefs, exhibits unique physical and mechanical properties such as high void ratio, low strength, and susceptibility to particle breakage. These characteristics reduce the bearing capacity and stability of pile foundations in calcareous sand foundations. This study investigates the bearing characteristics of high-strength preloaded expansion piles in calcareous sand foundations, taking into account the influence of HSCA high-performance expansion agent dosage through a series of indoor model tests and in-situ tests. The research delves into the load-settlement curves of expansion piles, the distribution of axial force and side resistance of piles, and the effects of Calcareous sand compaction and reinforcement around the piles. The results indicate that adding the HSCA high-performance expansion agent results in compaction preloading of the Calcareous sand around the pile, significantly increasing the expansion stress on the pile side, thereby enhancing the resistance on both the pile side and pile tip. When the expansion agent dosage is 20%, the ultimate bearing capacity can be increased by 56%, and the ultimate side resistance by 63%. The Coulomb strength theory of non-cohesive soil is employed to accurately calibrate the incremental side resistance of the expansion section. A prediction model for the bearing capacity of the expansion pile is established by combining the side resistance prediction model with the ultimate side resistance load-sharing ratio. The research outcomes provide important guidance for the optimization, design, and construction of high-strength preloaded expansion piles in calcareous sand foundations.

Horizontal Cyclic Bearing Characteristics of Bucket Foundation in Sand for Offshore Wind Turbines

During the service period, the offshore wind turbine foundation mainly bears the wind load from the upper structure and the periodic loads such as wave load and sea currents from the lower structure. Long-term cyclic loads have an important impact on the cumulative deformation, foundation stiffness changes, and horizontal ultimate bearing capacity of the offshore wind turbine bucket foundation. This paper conducts cyclic loading tests on mono-bucket foundations under unidirectional and multidirectional cyclic loading conditions based on the multidirectional intelligent cyclic loading system of offshore wind turbine foundations and analyzes the cumulative effects of the loading direction, vertical load, and drainage status on the mono-bucket foundation during the cyclic loading process, effects of rotation angle, cyclic stiffness, and monotonic bearing capacity of foundation after cycles. The research results show that multidirectional cyclic loading significantly reduces the cyclic cumulative rotation angle of the mono-bucket foundation, and the maximum reduction rate can reach more than 50%. After unidirectional and multidirectional cyclic loading, the bearing capacity of the bucket foundation can be increased by up to 30% and 20%, respectively. At the same time, this paper proposes calculation formulas for vertical load, number of cyclic loading, and normalized cumulative rotation and establishes a calculation method for vertical load and bearing capacity of the foundation after cycles.

The Effect of Footing Shape on the Bearing Capacity of Shallow Foundations: A Review

The Effect of Footing Shape on the Bearing Capacity of Shallow Foundations: A Review

Bearing characteristics and continuous–discontinuous numerical analysis of a pressure grouting pile in a calcareous sand foundation

The complex mechanical characteristics of calcareous sand complicate comprehensive analysis of the bearing characteristics of pressure grouting piles. The bearing mechanism of pressure grouting piles is unclear. Field tests of the bearing characteristics of pressure grouting piles in calcareous sand foundations were carried out. On the basis of the field test data, the coupled finite difference method (FDM) and discrete element method (DEM) were applied to explore the settlement characteristics. The force transfer laws in calcareous sand foundations are analyzed using complex network theory. The results show that the ultimate bearing capacity of pressure grouting piles increases significantly with increasing pile diameter. An increase in the pile‒soil interface friction coefficient can increase the pile side friction resistance, which can then increase the ultimate bearing capacity of the pile foundation. The friction coefficient of calcareous sand foundations can also increase the ultimate bearing capacity of pile foundations. However, the settlement of the pile foundation also increases. The axial force of the grouting pile gradually increases as the burial depth increases. When the pile bottom is reached, the axial force of the pile body clearly increases. This study presents an effective tool for the comprehensive analysis of the bearing characteristics of pressure grouting in calcareous sand foundations.

Shear properties of jointed dual-pylon of the cable-stayed bridge with separated unequal-width decks under asymmetric load

The significant load disparity between the two decks of a cable-stayed bridge with separated unequal-width decks results in complex asymmetric static effects in the jointed dual-pylon. To investigate the structural behaviour and reliability of the jointed dual-pylon under asymmetric loads, a 1:30 scaled model test and numerical simulation were conducted based on the world's first road-railway same-level cable-stayed bridge with jointed pylons. The test results indicate when the unbalanced horizontal force of the jointed dual-pylon structure reaches its maximum during the service phase, the stress at the dual-pylon connectivity node remains relatively low, indicating good shear resistance of the dual-pylon connectivity node. Structural failure occurs when the load reaches 1.82 times the maximum shear stress at the tower column merging section, and the railway beam will experience severe cracking and stiffness degradation, ultimately leading to loss of bearing capacity. The calculation results further reveal that under the combined action of dead load, full-span moving load, and lateral wind load, the minimum calculated nonlinear stability coefficient of the dual-pylon connectivity node is 1.65. Moving load and longitudinal wind load have minimal impact on the nonlinear stability coefficient, and the dead load and lateral wind load primarily govern the failure of the dual-pylon connectivity node.

Evaluation of Permeable Piles Foundation Performance in Liquefiable Soils under Seismic Loading

The use of permeable piles as an effective drainage method in liquefiable sites has become widely accepted. In this study, the seismic response of both the liquefiable soil and the pile was simulated using FLAC3D software to validate the anti-liquefaction performance of the permeable pile. A group of permeable piles designed according to the China foundation code were numerically modeled with various opening ratios (i.e. area of openings/total surficial area). The numerical results showed that the permeable pile is able to enhance liquefaction resistance by dissipating excess pore water through the drainage holes. The bending moments and axial force of the permeable pile decrease but the ultimate bearing capacity increases in the process of drainage. It is found that the excess pore water pressure ratio (EPWPR) of soil around permeable pile under seismic loading reduces rapidly with increasing opening ratio, but the excess pore water pressure tends to keep nearly a stable level once the opening ratio is beyond a critical value of 0.5%. As a result, the critical value of the opening ratio may be considered as the optimum parameter to design the permeable pile against liquefaction.

Enhanced Bearing Capacity Prediction Using Hybrid Tree-Based Ensemble Learning with Advanced Meta-Heuristic Optimization

Abstract The accurate prediction of soil bearing capacity remains a critical challenge in geotechnical engineering, particularly given the complex non-linear relationships between soil properties and foundation performance. Traditional analytical methods often struggle to capture these complexities, leading to potential overestimation or underestimation of bearing capacity across different footing types. This study investigates the application of machine learning techniques for predicting soil bearing capacity across different footing types. The research utilized 200 datasets, comprising 175 institutional sources and 25 laboratory Direct Shear Test experiments, with an 80-20 split ratio for model development and validation. A Hybrid Tree-Based Ensemble Learning (HTBEL) methodology was developed and compared against conventional models (M5P, CatBoost, AdaBoost, SVR, and Decision Tree) and Terzaghi analytical equation. The HTBEL model demonstrated superior predictive accuracy with R² values exceeding 0.96 across all footing types, maintaining errors below 5% throughout the sample range. Square footings showed the highest bearing capacity (median ~3,400 kN/m²) due to favorable area-to-depth ratio, followed by circular footings (~3,200 kN/m²) benefiting from symmetrical stress transmission, while strip footings (~2,000 kN/m²) showed lower performance due to concentrated stress distribution along their length. Clustering analysis identified optimal configurations at 3 clusters (Silhouette Score: 0.5236) and 10 clusters (0.5315). This research establishes HTBEL as a robust methodology for bearing capacity prediction in geotechnical engineering applications.

Research on Improving the Horizontal Bearing Performance of Wind Power Pile Foundation with Added Wing Structure

The growing recognition of renewable energy’s importance, particularly its role in sustainability, has propelled wind energy to a prominent position. Receiving substantial global policy support due to its unique advantages, wind energy has seen a significant increase in installed turbine capacity. Consequently, expectations for the foundational bearing performance of these turbines have heightened, reflecting the enhanced focus on sustainable energy solutions. In response to these demands, this research introduces an innovative single pile foundation design that aims to elevate bearing capabilities to new heights. This research delves into the horizontal bearing properties of this novel foundation and the stress-strain dynamics of geotechnical materials under loading conditions. To achieve this, we utilize the Gudehus-Bauer subplastic model, specifically tailored for coastal sands within the ABAQUS finite element analysis software. Calibration and verification of the Gudehus-Bauer model’s parameters were meticulously conducted based on laboratory tests focusing on the coastal sands of the Yangtze River basin in China, enabling the development of a precise finite element model for the new single pile foundation in sandy coastal soils. Our findings reveal that this reinforced single pile foundation not only mirrors the horizontal bearing capacity and failure mechanisms of traditional designs but also surpasses them in performance. Numerically, this innovative structure boasts a remarkable 19.34% increase in horizontal ultimate bearing capacity and a minimum of 21.91% reduction in maximum displacement compared to standard single piles. These results underscore the superior horizontal bearing performance of our novel foundation design, which not only enhances structural integrity but also aligns with the principles of sustainable engineering by optimizing material usage, reducing environmental impact, and contributing to the broader goal of promoting renewable energy as a sustainable energy source.

Three-Dimensional Stratigraphic Structure and Property Collaborative Modeling in Urban Engineering Construction

In urban engineering construction, ensuring the stability and safety of subsurface geological structures is as crucial as surface planning and aesthetics. This study proposes a novel multivariate radial basis function (MRBF) interpolant for the three-dimensional (3D) modeling of engineering geological properties, constrained by the stratigraphic structural model. A key innovation is the incorporation of a well-sampled geological stratigraphical potential field (SPF) as an ancillary variable, which enhances the interpolation of geological properties in areas with sparse and uneven sampling points. The proposed MRBF method outperforms traditional interpolation techniques by showing reduced dependency on the distribution of sampling points. Furthermore, the study calculates the bearing capacity of individual pile foundations based on precise stratigraphic thicknesses, yielding more accurate results compared to conventional methods that average these values across the entire site. Additionally, the integration of 3D geological models with urban planning facilitates the development of comprehensive urban digital twins, optimizing resource management, improving decision-making processes, and contributing to the realization of smart cities through more efficient data-driven urban management strategies.

Practical application of CS-CG Stabilised soil in subgrade construction

ABSTRACT To enhance the water stability and bearing capacity of the Shandong Ming Dong Expressway's soaked subgrade, carbide slag (CS) and coal gangue powder (CG) were used as stabilisers. Stabiliser dosages of 5%, 10%, and 15%, with the CS:CG ratios of 0:100, 30:70, 50:50, 70:30, and 100:0, were tested. The study evaluated the performance of CS-CG stabilised soil through unconfined compressive strength (UCS) tests at 7 and 28 days, six dry-wet cycles, a 30-day water immersion test, pH test, swell rate test, XRD, SEM, and MIP analyses. A UCS prediction model for CS-CG stabilised soil under dry-wet cycles was established. Results showed that CS-CG-10%-(70:30) achieved a UCS of 5.87 MPa after 28 days, decreasing to 4.77 MPa after six dry-wet cycles, indicating excellent bearing capacity and water stability. Increasing CS content improved UCS after 30 days’ immersion, reaching 5.74 MPa for CS-CG-10%-(70:30). The CS-CG mix produced hydration products like C-(A)-S-H gel, Ca(OH)2 crystals, and ettringite, enhancing pore structure and UCS. More dry-wet cycles increased hydration products and pore diameter, causing an initial UCS drop before stabilisation. The UCS prediction model using the Exp3p2 ( Y = e ( A X 2 + BX + C ) ) equation offers higher accuracy, supporting strength prediction. The study found that CS-CG stabilised soil behaves similarly to cement-stabilised soil in settlement.

Fluid-Structure Interaction Lubrication Analysis of Compliant Journal Bearing Lubricated with Non-Newtonian Plastic Fluid

Abstract High-viscosity plastic fluids and polymer liners are expected to improve the lubrication and load-carrying performance of low-speed and heavy-load journal bearings. The objective of this paper is to investigate the elastohydrodynamic lubrication performance of compliant journal bearings lubricated with non-Newtonian plastic fluids (following the Herschel-Bulkley model) using computational fluid dynamics (CFD) and fluid-structure interaction (FSI) methods. The following data are obtained: fluid film pressure, total bearing deformation, cavitation volume fraction, bearing capacity, and coefficient of friction. The simulation results are in close agreement with the data reported in the existing literature. A comparative analysis of the lubrication characteristics of journal bearings with Babbitt metal, PEEK, and PTFE liners at varying rotational speeds is presented. The effects of yield stress, power-law index, elastic modulus, and liner thickness on the lubrication characteristics are investigated. The results indicate that the power-law index of non-Newtonian plastic fluids has a greater influence on the bearing lubrication performance than the yield stress. Increasing the power-law index could improve the bearing capacity and reduce the coefficient of friction. The research provides a theoretical basis for the application of non-Newtonian plastic fluid-lubricated polymer journal bearings in low-speed and heavy-load equipment.

Shelf-Stable Sporosarcina pasteurii Formulation for Scalable Laboratory and Field-Based Production of Biocement.

Biocement is an environmentally friendly alternative to traditional cement that is produced via microbially induced calcium carbonate precipitation (MICP) and has great potential to mitigate the environmental harms of cement and concrete use. Current production requires on-site bacterial cultivation and the application of live culture to target materials, lacking the convenience of stable formulas that enable broad adoption and application by nonscientific professionals. Here, we report the development of a dry shelf-stable formulation of Sporosarcina pasteurii, the model organism for biocement production. At laboratory scale, when inoculated at an equivalent concentration of viable cells, we show that this formulation produces biocement equal in strength to that produced using live cell cultures. We further demonstrate that this formulation forms biocement in the field within 24 h, leading to ground improvement with increased bearing capacity. These results illustrate that preserved, shelf-stable bacteria can contribute to rapid biocement production and can be adopted for scaled geotechnical and construction purposes.

Seismic Performance and Flexural Capacity Analysis of Embedded Steel Plate Composite Shear Wall Structure with Fiber-Reinforced Concrete in the Plastic Hinge Zone

Due to its high axial bearing capacity and good ductility, the embedded steel plate composite shear wall structure has become one of the most widely used lateral force-resisting structural members in building construction. However, bending failure is prone to occur during strong earthquakes, and the single energy dissipation mechanism of the plastic hinge zone at the bottom leads to the concentration of local wall damage. To improve the embedded steel plate composite shear wall structure, the plastic hinge zone of the composite shear wall is replaced by fiber-reinforced concrete (FRC) and analyzed by ABAQUS finite element simulation analysis. Firstly, the structural model of the embedded steel plate composite shear wall structure with FRC in the plastic hinge zone is established and the accuracy of the model is verified. Secondly, the effects of steel ratio, longitudinal reinforcement ratio, and FRC strength on the bearing capacity of composite shear walls are analyzed by numerical simulation. Finally, a method for calculating the embedded steel plate composite shear wall structure with FRC in the plastic hinge zone is proposed. It is shown that the displacement and load curves and failure modes of the model are basically consistent with the experimental results, and the model has high accuracy. The axial compression ratio and FRC strength have a great influence on the bearing capacity of composite shear walls. The calculation formula of the normal section bending capacity of the embedded steel plate composite shear wall structure with FRC in the plastic hinge zone is proposed. The calculated values of the bending capacity are in good agreement with the simulated values, which can provide a reference for its engineering application.

Repeated axial compressive performance of GCFST columns: Test investigation and numerical analysis

Geopolymer concrete (GC) is green and environmentally friendly. In order to comprehensively study the mechanical properties and influence mechanism of geopolymer concrete-filled steel tubular (GCFST) columns under various working conditions, this study takes the strength grade of geopolymer concrete, length-diameter ratio and wall thickness of steel tube as design parameters. Eight GCFST columns are designed and the compressive performances are conducted under repeated axial compression. The load–displacement curve, the skeleton curve, the characteristic load and displacement, the ductility, and the energy dissipation were analyzed. Furthermore, the numerical analysis models were established through finite element software and the test results were compared with the simulation results to verify the accuracy of the finite element model. The results indicate that under different length-diameter ratios, the variation trends of the load–displacement curves for the specimens are slightly different, while the stiffness degradation curves present similar variation laws. The design parameters have significant effects on the bearing capacity, average compressive force, and energy dissipating capacity of the specimens. The simulation results are in good agreement with the experimental results. Research results show the excellent bearing capacity of GCFST columns and the precision of finite element calculation results, which can provide a reference for related experimental research.

Determination of the bearing capacity of reinforced concrete rectangular contoured slabs, taking into account the impact of the spacer

Determination of the bearing capacity of reinforced concrete rectangular contoured slabs, taking into account the impact of the spacer