• Structural Engineering and Mechanics
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• v.45 no.1
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• pp.129-144
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• 2013

Load-carrying capacity of combined members consisted of inner and sleeved tubes subjected to axial compression was investigated in this paper. Considering the initial bending of the inner tube and perfect elasto-plasticity material model, structural behavior of the sleeved member was analyzed by theoretic deduction, which could be divided into three states: the elastic inner tube contacts the outer sleeved tube, only the inner tube becomes plastic and both the inner and outer sleeved tubes become plastic. Curves between axial compressive loads and lateral displacements of the middle sections of the inner tubes were obtained. Then four sleeved members were analyzed through FEM, and the numerical results were consistent with the theoretic formulas. Finally, experiments of full-scale sleeved members were performed. The results obtained from the theoretical analysis were verified against experimental results. The compressive load-lateral displacement curves from the theoretical analysis and the tests are similar and well indicate the point when the inner tube contacts the sleeved tube. Load-carrying capacity of the inner tube can be improved due to the sleeved tube. This paper provides theoretical basis for application of the sleeved members in reinforcement engineering.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.1
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• pp.41-51
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• 2006

This paper concerns the effect of lining interface adherence on the lining's load carrying capacity. A series of reduced scale laboratory tests and finite element anlayses were carried out with the aim of gaining insight into the effect of shotcrete lining adherence on the load carrying capacity of double shell lining. The results indicated among other things that the load carrying capacity of a double shell tunnel is significantly affected by the adherence between layers. Also revealed was that for cases with low lining layer adherence stress concentration may occur due to relative movement between the lining layers with this trend being more pronounced with increasing tunnel cover depth. Practical implications from the results of this study are discussed in great detail.

• Steel and Composite Structures
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• v.35 no.3
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• pp.371-384
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• 2020

The steel-concrete double composite girder in the negative flexural region combines an additional concrete slab to the steel bottom flange to prevent the local steel buckling, however, the additional concrete slab may lower down the neutral axis of the composite section, which is a sensitive factor to the tensile stress restraint on the concrete deck. This is actually of great importance to the structural rationality and durability, but has not been investigated in detail yet. In this case, a series of 5.5 m-long composite girder specimens were tested by negative bending, among which the bottom slab configuration and the longitudinal reinforcement ratio in the concrete deck were the parameters. Furthermore, an analytical study concerning about the influence of bottom concrete slab thickness on the cracking and sectional bending-carrying capacity were carried out. The test results showed that the additional concrete at the bottom improved the composite sectional bending stiffness and bending-carrying capacity, whereas its effect on the concrete crack distribution was not obvious. According to the analytical study, the additional concrete slab at the bottom with an equivalent thickness to the concrete deck slab may provide the best contributions to the improvements of crack initiation bending moment and the sectional bending-carrying capacity. This can be applied for the design practice.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.4
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• pp.147-151
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• 2007

Load testing is an effective means in calculating the rating value of bridge. In Korea, load carrying capacity of bridge is modified by response modification factor that is determined from comparisons of measured values and analysis results. This paper presents the development of a method for determining the response modification factor, using traffic load. The proposed method is based on the results of computer simulations of traffic action effects. A comparison between the proposed method and the present method shows good agreement in estimating the modified load carrying capacity of bridges.

• International Journal of High-Rise Buildings
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• v.3 no.4
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• pp.297-304
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• 2014

Recently, there have been some reported examples of structural collapse due to gravity, subsequent to damage from accident or an excitation that was not prepared for in the design process. A close view of new concepts, such as a redundancy and key elements, has been taken with the aim of ensuring the robustness of a structure, even in the event of an unexpected disturbance. The author previously proposed a sensitivity index of the vertical load carrying capacity to member disappearance for framed structures. The index is defined as the ratio of the load carrying capacity after a member or a set of an adjacent member disappears, to the original load carrying capacity. The member with the highest index may be regarded as a key element. The concept of bio-mimicry is being applied to various fields of engineering, and tree-shaped structures are sometimes used for the design of building structures. In this study a sensitivity analysis is applied to the irregular-framed structures such as tree-shaped structures.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.53-58
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• 2009

The importance of process for repair and reinforcement of the bridge is increasing because of the lack of the fatigue load and stress, a lowering of the bridge load carrying capacity owing to impact and oscillation, deterioration on cultivation periods of the bridge, etc. Typically the experimenter values the bridge load carrying capacity by the real rating factor and response modification factor in bridge load rating through static load test and dynamic load test. But the error occurred in reliability of response modification factor in bridge load rating according to experience of experimenter. so tests of connecting probability theory and valuation of the bridge recently. The study is to compute the real load carrying capacity of the bridge and the rating factor and response modification factor on grade of the bridge, and calculate the probability of over-loaded truck load from Weigh In Motion(WIM) Data in FORTRAN programming applying to Monte-Carlo Simulation. At the result of this study, it is acquired that the new grade is computed for the probability of over-loaded truck load and surface inspection. The A grade is over 1.95, B grade is $1.55{\sim}1.94$, C grade is $1.26{\sim}1.54$, D grade is $1.14{\sim}1.25$, E grade is under 1.13 of rating factor, respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.4
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• pp.53-60
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• 2019

In this study, a method for updating the finite element model of bridges with genetic algorithm using static displacement were presented, and verified this method using field test data for PSC girder bridge. As a field test, static load test and pseudo-static load test were conducted, and updated the finite element model of test bridge using each test data. Finally, evaluated the bridge load carrying capacity with updated model using pseudo-static load test's displacement data. To evaluate the bridge load carrying capacity, KHBDC-LSD, KHBDC and AASHTO LRFD's live load model were used, and compared the each results.

• Composites Research
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• v.15 no.3
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• pp.11-17
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• 2002

Cracking of the reinforcements is a significant damage mode in particle or short-fiber reinforced composites because the broken reinforcements lose load carrying capacity. This paper deals with elastic stress distributions and load carrying capacity of intact and cracked ellipsoidal inhomogeneities. Three dimensional finite element analysis has been carried out on intact and broken ellipsoidal inhomogeneities in all infinite body under pure shear. For the intact inhomogeneity, the stress distribution is uniform in the inhomogeneity and non-uniform in the surrounding matrix. On the other hand, for the broken inhomogeneity, the stress in the region near crack surface is considerably released and the stress distribution becomes more complex. The average stress in the inhomogeneity represents its load carrying capacity, and the difference of average stresses between the intact and broken inhomogeneities indicates the loss of load carrying capacity due to cracking damage. The broken inhomogeneity with higher aspect ratio maintains higher load carrying capacity.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.2
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• pp.1-9
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• 2020

This study intends to analyze the relationships between images of arboreta or botanical gardens and the policy supports related to carrying capacity. For this purpose, a questionnaire survey was distributed to 723 public sites nationwide. The results consisting of an exploratory factor analysis, a confirmatory factor analysis, a correlation analysis, and a structural equation method showed that the images of the arboretum or botanical gardens contained 3 factors: cognitive, affective and shape factors. The cognitive factors greatly affected the policy support related to carrying capacity. The policymakers of the arboretum or botanical gardens can consider cognitive elements of images as important aspects in the planning and management factors to improve the support of visitors related to the policies of carrying capacity for sustainable use.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.2
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• pp.15-21
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• 2010

Structural analysis used to evaluate the load carrying capacity of a bridge should implement behavioral characteristics similar to the actual behaviors of the structure through loading tests, but it is not feasible in many cases due to the behavioral characteristics of points, inadequate modeling method in structural analysis, errors in loading tests, changes in strength and rigidity resulting from cross-sectional damage, etc. This problem can be more serious if bridge bearings have been damaged or were not installed and, consequently, the bearings do not function properly. This study produced results similar to actual behaviors using a structural analysis model built with support moment derived from the difference $\Delta{\delta}$ between measured deflection obtained by confining the cantilever segment of a solid beam and calculated deflection under a unrestrained condition. When the load carrying capacity of a bridge in operation was evaluated in consideration of the confinement condition of supports, the result was 15~19% lower than load carrying capacity calculated by the existing method.