• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.935-938
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• 2001

This paper reports the relation of concrete setting characteristic and lateral pressure in mass concrete wall such as side wall of LNG underground storage tank. In order to estimate the lateral pressure, initial setting time of low heat cement concrete with type of mineral admixture was measured for three concrete mixtures(W/P=41.6%) containing limestone powder, fly ash, and slag powder. As a result, the lateral pressure of the concrete containing limestone powder was the smallest than those of other concretes as well as the initial setting time.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.130-138
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• 2015

In this study, to examine the application of cast-in-place of high-flowable and high-strength concrete, an experimental study on the lateral pressure of a formwork was preformed. The experiment specimens, which have different casting height and casting speed were prepared. The lateral pressure and the change of temperature from test specimens were obtained. The maximum lateral pressure was shown to lateral pressure of fresh concrete. Immediately after placing, the lateral pressure starts to decrease and, after 12 hours, it showed a stabilization. The decreased tend of the lateral pressure was similar with normal-strength concrete, which appears stabilization after 3~4 hours from casting completion. The more casting speed is fast, the more maximum lateral pressure is high, but pressure reduction with the lapse of time was nearly similar. In addition, it was found that there was no direct relation between the hydration heat and the lateral pressure reduction.

• Structural Engineering and Mechanics
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• v.84 no.2
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• pp.239-251
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• 2022

The use of lateral reinforcement in confined concrete columns can improve bearing capacity and deformability. The lateral responses of lateral reinforcement significantly influence the effective confining pressure on core concrete. However, lateral strain-axial strain model of concrete columns confined by lateral reinforcement has not received enough attention. In this paper, based on experimental results of 85 concrete columns confined by lateral reinforcement under axial compression, the effect of unconfined concrete compressive strength, volumetric ratio, lateral reinforcement yield strength, and confinement type on lateral strain-axial strain curves was investigated. Through parameter analysis, it indicated that with the same level of axial strain, the lateral strain slightly increased with the increase in the unconfined concrete compressive strength, but decreased with the increase in volumetric ratio significantly. The lateral reinforcement yield strength had slight influence on lateral strain-axial strain curves. At the same level of lateral strain, the axial strain of specimen with spiral was larger than that of specimen with stirrup. Furthermore, a lateral strain-axial strain model for concrete columns confined by lateral reinforcement under axial compression was proposed by introducing the effects of unconfined concrete compressive strength, volumetric ratio, confinement type and effective confining pressure, which showed good agreement with the experimental results.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.225-226
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• 2023

This study examined the lateral deformation of double deck plate wall formworks against the lateral pressure of fresh concrete and then compared with the construction specification.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.278-283
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• 1995

In this study, the influence of the lateral pressure on the interface shear transfer of concrete has been investigated experimentally. A total of 21 specimens has been tested at the laboratory. The lateral pressure intensities in the tests have been taken as 0, 7, 14, 28, and 35kg/$\textrm{cm}^2$ for the specimens, the compressive strengths of which are either 180, 400 or 550kg/$\textrm{cm}^2$. The linear regression analysis based on the test results has shown relatively good agreements with the values given in the shear friction theory.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.1
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• pp.83-91
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• 2000

The purpose of this study is to estimate quantitatively lateral pressure of super-workable fresh concrete applied to form-work of prototype structures, such as tall wall, retaining wall and beam. As a result of this experiment, a function applicable to design a form work system and to predict lateral pressure curve is formulated . Super-workable concrete may be used for the structures reinforced with dense re-bar like box culvert to place concrete at a time, and this study for lateral pressure of super-workable concrete may be useful for form design.

• Journal of Korean Association for Spatial Structures
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• v.17 no.4
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• pp.167-174
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• 2017

The F3D(Free-Form Formwork 3D Printer) technology that manufactures EPS(Expanded Polystyrene) formworks for irregular-shaped concrete structures by 3D printers was developed to reduce the cost and time. Because of weak strength and low elastic modulus of the EPS, structural performance including lateral pressure by fresh concrete of the formwork that consisted of EPS should be investigated. In order to calculate lateral pressures acting on formwork, several variables including sizes, shapes of formwork, tangential force(fricition) between fresh concrete and formwork, and material properties of fresh concrete should be considered. However, current regulations have not considered the properties of concrete, only focused on vertical formwork. Galleo introduced 3-dimensional finite element analysis models to calculate lateral pressure on formwork. Thus, proposed finite element analysis model based on previous studies were verified for vertical formwork and irregular-shaped formwork. The test results were compared with those by FEM analysis. As a result, the test agrees well with the analysis.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.507-510
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• 2005

Euro form which constructs the present RC structures is used widely by the form method of construction of a wall type structure had much consumption of the human power and equipments by the assembly and the demolition, and the complement was required according to demerit with much leakage of cement paste by the form joint, so it developed the new pillar type form system. On the study, in order to consider the modification characteristic by lateral pressure which does the influence most important for the new developed pillar type form system performance, research of a paper manufactured a miniature wall form model, and advanced performance evaluation focusing on lateral pressure. Moreover, lateral pressure evaluation of a new style system was actually gone on through the on-site experiment about a part of wall type srutcture spot for a model experiment and its result on the foundation which is the purpose in evaluating on-site application possibility propriety at the foundation time of wall type concrete structure construction of a pillar type form system.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.547-552
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• 1998

Lateral pressure by circular reinforcement greatly enhances the maximum strength and ductility of spiral columns. The lateral confinement effects will be improves ductility of high-strength concrete. The major purpose of this paper is to study on the improvements of maximum strength and strain at that point of spiral concrete columns subject to axial loads. For this purpose, this study collected the other analytical results and the experimental data that has been performed by a lot of worldwide researchers and also analyzed it statistically. As the result, the theoretical equation for predict maximum strength and strain at that point was proposed. It is based on calculation of lateral confinement pressure generated by circular reinforcement, and the resulting improvements in strength and ductility of confined concrete.

• KCI Concrete Journal
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• v.13 no.1
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• pp.53-60
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• 2001

Tests of cylindrical concrete specimens under lateral confining pressure of up to 5,000 psi were conducted for two different axial loading cases: monotonic compression and monotonic tension. The purpose of this experimental investigation is to provide stress-strain characteristics of plain concrete in triaxial stress conditions. Lateral confining pressure levels, loading rates, and strength of concrete specimens are varied as parameters. The loading rates are $34.75$\times$10^{-5}$ in/in/sec for fast, $\times$$6.95x10^{-5}$ in/in/sec for normal. and $0.579$\times$10^{-5}$ in/in/sec for slow loading cases. The concrete specimens used in the experiment have compressive strength of 3,500 psi and 6,500 psi, respectively. Findings of this experiment include dependency of the stress-strain behavior of concrete on the above parameters under two different types of loading conditions. The parametric study includes a series of 106 triaxial tests.