• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.669-675
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• 2020

This research has focused on comparing the capacity predicted by the theoretical formula with the one measured by field load tests to examine characteristics of the bearing capacity of a helical pile. The helical pile is featured by a central shaft with one or more helical-shaped bearing plates. Being established by a small rotary attached to an excavator that applies toque, the helical piles can be readily constructed at narrow sites, especially in an urban area with relatively less noise than the others requiring driving and excavation. Although many cases of the helical pile constructions can be recently found, the bearing capacity of the pile has been limitedly studied. To this end, this contribution analyzes and presents comprehensive results of the ten field loading tests with an application of different parameters depending on joint condition and specification of the helical piles, and types of tests and grouting.

• International Journal of Safety
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• v.9 no.2
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• pp.16-21
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• 2010

In this study, the variations of transformed impact factors and load carrying capacity of highway bridges measured from the state of expansion joint are evaluated. the field loading tests were performed on the highway bridge with damaged expansion joint to investigate the variation of the load carrying capacity. From the field loading tests in case that damaged expansion joint exist or do not exist, the static displacements and dynamic displacements were measured, and TIF were calculated, respectively. dynamic test is performed in order to estimate dynamic displacement and TIF according to the level of damage of expansion joint. From the results of TIF, the load carrying capacity of highway bridges with damaged expansion joint were estimated.

• Geomechanics and Engineering
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• v.23 no.1
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• pp.15-30
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• 2020

The probabilistic bearing capacity of a strip footing placed on the edge of a purely cohesive reinforced soil slope is computed by combining lower bound finite element limit analysis technique with random field method and Monte Carlo simulation technique. To simulate actual field condition, anisotropic random field model of undrained soil shear strength is generated by using the Cholesky-Decomposition method. With the inclusion of a single layer of reinforcement, dimensionless bearing capacity factor, N always increases in both deterministic and probabilistic analysis. As the coefficient of variation of the undrained soil shear strength increases, the mean N value in both unreinforced and reinforced slopes reduces for particular values of correlation length in horizontal and vertical directions. For smaller correlation lengths, the mean N value of unreinforced and reinforced slopes is always lower than the deterministic solutions. However, with the increment in the correlation lengths, this difference reduces and at a higher correlation length, both the deterministic and probabilistic mean values become almost equal. Providing reinforcement under footing subjected to eccentric load is found to be an efficient solution. However, both the deterministic and probabilistic bearing capacity for unreinforced and reinforced slopes reduces with the consideration of loading eccentricity.

• Journal of the Korean Geosynthetics Society
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• v.14 no.4
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• pp.45-58
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• 2015

Even though the plate bearing test (PBT) to evaluate the load baring capacity and the field density test to evaluate the relative density are mainly used for quality control of soil compaction in Korea, use of the dynamic cone penetrometer test (DCPT) and the dynamic plate bearing test (DPBT) considering economic feasibility, rapidity, and suitability for field conditions increase to use for quality control of soil compaction. In this study, bearing capacity and relative density of subgrade with thickness of 20 cm, 30 cm, and 40 cm are estimated using PBT, DCPT, DPBT and field density test in three field compaction tests, and the relationship among various compaction evaluation methods is analyzed and discussed.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.457-462
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• 2022

This study is about the case applied of a shallow foundation reinforcement method for a low/mid-rise building where a relatively small load is applied by using a soil stabilized material that utilizes recycled resources. First, laboratory mixing test was conducted for four mixing ratios in order to derive the optimal mixing ratio in the field. Using the derived optimal mixing ratio, it was applied as a shallow foundation for the building in the field. The field application method used a simple process of compaction by the soil mixedure with the original soil and the soil stabilized material in the field. After field application, a plate bearing test was performed on one original ground and two improved ground to confirm the allowable bearing capacity. As a result of checking the bearing capacity, it was found that sufficient bearing capacity was exhibited.Therefore, it was confirmed that it can be used as a shallow foundation for the building.

• Journal of the Korean Geosynthetics Society
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• v.7 no.2
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• pp.15-21
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• 2008

The advantages of prefabricated vertical drains over conventional sand drains include their relatively low costs, less disturbance to the soil mass, the easinees of installation, and their flexibility which ensures the integrity of the drains during installation. This study tested the change of discharge capacities with respect to the hydraulic gradients for each lateral pressure. From the test results, as increases the overburden pressure, the clay soil is being consolidated, and also lateral pressure to the PVD specimen is increased. Therefore, the discharge capacity is decreased. The size of opening space in the core of PVDs is proportionally related to the discharge capacity. The numerical analysis was performed with utilizing computer simulation with considering field conditions. The results of numerical analysis are compared well with the field measurements.

• Journal of Applied Reliability
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• v.13 no.4
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• pp.241-252
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• 2013

Because of financial and safety concerns, there are needs for more accurate prediction of bridge behavior. Underestimation of the bridge load carrying capacity can have serious economic consequences, as deficient bridges must be repaired or rehabilitated. Therefore, the knowledge of the actual bridge behavior under live load may lead to a more realistic calculation of the load carrying capacity and eventually this may allow for more bridges to remain in service with or without minor repairs. The presented research is focused on the reliability evaluation of the actual load carrying capacity of existing bridges based on the field testing. Seventeen existing bridges were tested under truck load to confirm their adequacy of reliability. The actual response of existing bridge structures under live load is measured. Reliability analysis is performed on the selected representative bridges designed in accordance with AASHTO codes for bridge component (girder). Bridges are first evaluated based on the code specified values and design resistance. However, after the field testing program, it is possible to apply the experimental results into the bridge reliability evaluation procedures. Therefore, the actual response of bridge structures, including unintentional composite action, partial fixity of supports, and contribution of nonstructural members are considered in the bridge reliability evaluation. The girder distribution factors obtained from the tests are also applied in the reliability calculation. The results indicate that the reliability indices of selected bridges can be significantly increased by reducing uncertainties without sacrificing the safety of structures, by including the result of field measurement data into calculation.

• Journal of the Korean Geotechnical Society
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• v.20 no.6
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• pp.29-40
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• 2004

The bearing capacity of drilled shaft is affected by several factors, such as shaft length, shape, surface roughness, young's modulus of geomaterials and shaft, soil strength, confining stress and so on. However, there has been no design method of drilled shaft considering all factors mentioned above. Moreover, since geomaterials are simply classified as sand, clay and rock, there was no design criterion for IGM (Intermediate Geomaterials). Therefore, the rigorous design approach of drilled shaft was not possible by classical design method. However, since these characteristics were not considered in classical theories, bearing capacity was generally different ken practical value. In this study, the bearing capacity of drilled shaft with the IGM's theory was compared with those of classical theories. The results showed that classical method showed smaller values of bearing capacity than those of field load transfer data. Moreover, the evaluated value of bearing capacity with IGM theory corresponded fairly well with those of field data.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.533-540
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• 2002

Recently, geogrid reinforcement has been applied tn the subgrade of the roadway and the railway on the compressible layered soil, and the relevant reserch on the reinforcing mechanism has been performed. In this study, mechanics of geogrid reinforcement and the parameters for the improvement of bearing capacity are evaluated and presented based on the case histories of the field load test on the geogrid-reinforced layered subgrade

• Coupled systems mechanics
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• v.12 no.2
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• pp.167-181
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• 2023

The determination of the blast protection level and the corresponding minimum load-bearing capacity for a laminated glass (LG) window is of crucial importance for safety and security design purposes. In this paper, the focus is given to the window response under near-field blast loading, i.e., where relatively small explosives would be activated close to the target, representative of attack scenarios using small commercial drones. In general, the assessment of the load-bearing capacity of a window is based on complex and expensive experiments, which can be conducted for a small number of configurations. On the other hand, nowadays, validated numerical simulations tools based on the Finite Element Method (FEM) are available to partially substitute the physical tests for the assessment of the performance of various LG systems, especially for the far-field blast loading. However, very little literature is available on the LG window performance under near-field blast loads, which differs from far-field situations in two points: i) the duration of the load is very short, since the blast wavelength tends to increase with the distance and ii) the load distribution is not uniform over the window surface, as opposed to the almost plane wave configuration for far-field configurations. Therefore, the current study focuses on the performance assessment and structural behaviour of LG windows under near-field blasts. Typical behavioural trends are investigated, by taking into account possible relevant damage mechanisms in the LG window components, while size effects for target LG windows are also addressed under a multitude of blast loading configurations.