• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.245-253
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• 2021

RC slab bridges account for the largest portion of deteriorated bridges in Korea. However, most RC slabs are not included in the first and second classes of bridges, which are subject to bridge safety management and maintenance. The highest damaged components in highway bridges are the subsidiary facilities including expansion joints and bearings. In particular, leakage through expansion joints causes deterioration and cracks of concrete and exposure of reinforced bars. Therefore, this study analyzed the effect of adhesion damage at expansion joints on the response of the deck in RC slab bridges. When the spacing between the expansion joints at both ends was closely adhered, cracks occurred in the concrete at both ends of the deck due to the resistance rigidity at the expansion joints. Based on the response results, the correlation analysis between displacements in the longitudinal direction of the expansion joint and concrete stress at both ends of the deck for each damage scenario was performed to investigate the effect of the occurrence of damage on the bridge behavior. When expansion joint devices at both sides were damaged, the correlation between displacement and stress showed a low correlation of 0.18 when the vehicles proceeded along all the lanes. Compared with those in the intact state, the deflections of the deck in the damaged case at both sides showed a low correlation of 0.34 to 0.53 while the vehicle passed and 0.17 to 0.43 after the vehicle passed. This means that the occurrence of cracks in the ends of concrete changed the behavior of the deck. Therefore, data-deriven damage detection could be developed to manage the damage to expansion joints that cause damage and deterioration of the deck.

• Journal of the Korean Society of Safety
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• v.31 no.3
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• pp.89-95
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• 2016

Lately, the high-strength concrete is often used to increase the lifespan of bridges. The benefits of using the high-strength concrete are that it increases the durability and strength. On the contrary, it reduces the cross-section of the bridges. This study conducted structural performance tests of the bridge deck slabs applying high-strength concrete. As result of the tests, specimens of bridge deck slabs were destroyed through punching shear. Moreover, the tests exposed that the high-strength concrete bridge deck slabs satisfy the flexural strength and the punching shear strength at ultimate limit state(ULS). Also, limiting deflection of the concrete fulfilled serviceability limit state(SLS) criteria. These results indicated that the bridge deck slabs designed by high-strength concrete were enough to secure the safety factor despite of its low thickness.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.49-57
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• 2014

A deterioration of typical reinforced concrete (RC) bridge deck is due to the use of calcium chloride, cracks and water penetration inside of the deck slab with steel reinforcement. In order to eliminate the defects of RC decks in terms of material, therefore, the steel-strapped deck system is studied and developed by maximizing the arching effect while the girders are restrained using straps in lateral direction to the bridge. This parametric study was performed to analyze the structural characteristics of steel-strapped deck, and to identify the factors of the thickness, span length and lateral restraint stiffness of deck slab considering the concrete non-linearity. Finally, a design equation, which is adequate to South Korea, is suggested.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.313-318
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• 2002

The use of carbon fiber rods is a promising technology of increasing flexural and shear strength of deficient reinforced concrete members. The purpose of this experimental study is to investigate the fatigue behavior and strengthening effects of the strengthened bridge deck with isotropic and othortropic carbon fiber rod. This study shows a fatigue loading, compliance and S-N Curve between strengthened isotropically and othortropically. Then estimate the effective fatigue behavior of RC slab using composite rods that are inserted in high special purposed polymer mortar.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.4
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• pp.30-38
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• 2017

Recently, research on the development of a composite slab system for shorting the construction period by simplifying the process by omitting the form work and the reinforcement placing is underway. The purpose of this study is to evaluate the long-term behavior of a simplified slab system that replaces the form work and tensile reinforcement using structural deck-plate and replaces the temperature reinforcement using steel fiber reinforced concrete. In the conventional composite deck-plate slab method, w.w.f is generally used for crack control by drying shrinkage. But previous research results by various researchers were pointed out it is not effective to control the shrinkage and temperature cracking. In this study, the long-term cracking and structural behavior of steel fiber reinforced deck plate slab specimen with two continuous spans constructed under typical load conditions were evaluated. Experimental results showed that the number and width of long-term cracks decreased remarkably in the simplified slab specimen, and the deflection was also decreased compared with conventional RC slab specimen. However, in the continuous end of the slab where the negative moment is applied, it is analyzed that reinforced details are necessary to control the crack width in the service load and to recover deflection at load removal.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.34-37
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• 2006

Accoarding as a specimen for reinforced concrete bridge deck was designed by each researcher's opinions, its size and shape was variable. Therefore, it makes difficult to comparison with other experiments. In the result of researching papers for design method of reinforced concrete bridge deck specimens, there is hardly found. The target of this study is introduction of the design method of a reinforced concrete bridge deck specimen. The most important point for the specimen design is materialization of the curvature of the real bridge deck. The result of this study appears that the specimens thickness effects highly to fit for the real reinforced concrete bridge deck's curvature.

• Journal of the Korea Concrete Institute
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• v.14 no.5
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• pp.668-676
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• 2002

Especially, when orthotropic material such as uni-dierectionally woven Carbon Fiber Sheet, resisting only the unidirectional tension, is used to strengthening bridge deck, the direction and width of the strengthening material should be considered very carefully. Thus, analysis of the failure characteristics and the premature failure mechanism of the strengthened decks based on the test results are required. In this study, the premature failure due to the interface debonding of strengthening material of the strengthened deck slab are inquired into failure mechanism through both experiments results and analyses with prototype strengthened deck specimens using carbon fiber sheet. From the test results, interface debonding of strengthening material is occured at the crack face

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.3 s.55
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• pp.145-154
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• 2009

Steel-Concrete Composite Deck with I-beam welded is lighter and easier to construct than conventional in situ reinforced concrete slabs due to the I-beam embedded in the corrugated slab. For the calculation of effective flexural rigidity of conventional reinforced concrete structures, methods suggested in Design Standard for Roads and Bridges and ACI have been used. In this paper, the calculation methods were applied to steel-concrete composite deck with I-beam welded and then results of the steel-concrete composite deck were compared with those of reinforced concrete slabs. In addition, applicability of the methods to steel-concrete composite deck with I-beam welded was estimated. In order to compare the effective flexural rigidity, flexural experiments were conducted. Fifteen slabs were built and the variables considered in the experiments were studs, length of the slab, shape of the section and connecting methods.

• Journal of the Korean Society of Industry Convergence
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• v.14 no.1
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• pp.1-7
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• 2011

Basalt originates from volcanic magma and flood volcanoes, a very hot fluid or semifluid material under the earth's crust, solidified in the open air. Basalt is a common term used for a variety of volcanic rocks, which are gray, dark in colour, formed from the molten lava after solidification. Recently, attention has been devoted to continuous basalt fibers (CBF) whose primary advantage consists in their low cost, good resistance to acids and solvents, and good thermal stability. In order to investigate reinforcement effect, this paper did FEM analysis with shell element. The result were as follows; BCF deck plate did elastic behavior to 450 kN, reinforcement effect of basalt fiber (BF) was less. But BCF's perpendicular deflection occurred little about 23 mm comparing with RC deck plate in load 627 kN. Stiffness was very improved by basalt fiber reinforcement.

• Journal of the Korea Concrete Institute
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• v.24 no.6
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• pp.677-684
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• 2012

In recent years, extension of life span of buildings is becoming an important issue in our society. To improve the life span of buildings, rhamen structure construction and long-spanned structures are advantageous. And in order to achieve this goal, structural elements of buildings must be light and slender. As an alternative method, general porous slabs are used frequently domestically and internationally. But the study on the porous slabs using T-deck plate and assembly of light weight precast construction is insufficient at present. In this study, flexural and fatigue tests were performed on six specimens to verify structural performance and serviceability. The main parameters of the specimens were light weight and T-deck plate construction possibility as well as slab thickness. The test results indicated that the strength of porous slabs using T-deck plate and assembly of light weight were much better than general RC slabs and porous slabs without T-deck plate. And stiffness was much better than that of other tested slabs.