• Title/Summary/Keyword: depth penetration

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Pile-soil-structure interaction effect on structural response of piled jacket-supported offshore platform through in-place analysis

  • Raheem, Shehata E Abdel;Aal, Elsayed M. Abdel;AbdelShafy, Aly G.A.;Fahmy, Mohamed F.M.;Mansour, Mahmoud H
    • Earthquakes and Structures
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    • v.18 no.4
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    • pp.407-421
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    • 2020
  • In-place analysis for offshore platforms is essentially required to make proper design for new structures and true assessment for existing structures, in addition to the structural integrity of platforms components under the maximum and minimum operating loads when subjected to the environmental conditions. In-place analysis have been executed to check that the structural member with all appurtenance's robustness have the capability to support the applied loads in either storm or operating conditions. A nonlinear finite element analysis is adopted for the platform structure above the seabed and pile-soil interaction to estimate the in-place behavior of a typical fixed offshore platform. The SACS software is utilized to calculate the dynamic characteristics of the platform model and the response of platform joints then the stresses at selected members, as well as their nodal displacements. The directions of environmental loads and water depth variations have significant effects in the results of the in-place analysis behavior. The most of bending moment responses of the piles are in the first fourth of pile penetration depth from pile head level. The axial deformations of piles in all load combinations cases of all piles are inversely proportional with penetration depth. The largest values of axial soil reaction are shown at the pile tips levels (the maximum penetration level). The most of lateral soil reactions resultant are in the first third of pile penetration depth from pile head level and approximately vanished after that penetration. The influence of the soil-structure interaction on the response of the jacket foundation predicts that the flexible foundation model is necessary to estimate the force responses demands of the offshore platform with a piled jacket-support structure well.

Evaluation of Adhesive Characteristics of Mixed Cross Laminated Timber (CLT) Using Yellow Popular and Softwood Structural Lumbers

  • Keon-Ho KIM;Hyun-Mi LEE;Min LEE
    • Journal of the Korean Wood Science and Technology
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    • v.52 no.1
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    • pp.58-69
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    • 2024
  • To evaluate the adhesive characteristics of mixed cross-laminated timber (CLT) using domestic softwoods structural lumber proposed by KS F 3020 and yellow poplar, penetration depth of adhesive and thickness of bonding line were analyzed based on the results of boiling water soaking delamination. 3 Types of adhesives and 2 types of major layer were divided into a 5 ply CLT using yellow popular as minor layer. The bonding performance of the mixed CLT as structural members was evaluated based on the KS F 2081. The thickness of bonding line between layers of the mixed CLT was measured with a scanning electron microscope, and the adhesive penetration depth in the layer members was measured with an optical microscope. As a result of boiling water soaking delamination test of mixed CLT, the CLT specimens using PRF and PUR adhesives met the requirements of KS F 2081. It was verified that the penetration path of the adhesive in the layes was mainly through the tracheid cell in the case of Japanese larch and Korean red pine layers, and through the vessel and radial tissue in yellow popular layers. The penetration depth of the adhesive was the highest for the PRF adhesive under the same pressing time conditions, and the thickness of the bonding line was in inverse proportion to the penetration depth in the case of the PUR adhesive.

THE EFFECTS OF INSTRUMENTATION WITH SOME ENDODONTIC IRRIGANTS ON THE APICAL SEAL OF ROOT CANAL (수종(數種) 근관세척액(根管洗滌液)이 근관폐쇠성(根管閉鎖性)에 미치는 영향(影響)에 관(關)한 연구(硏究))

  • Lim, Sung-Sam
    • Restorative Dentistry and Endodontics
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    • v.11 no.1
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    • pp.27-32
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    • 1985
  • The purpose of this study was to examine the influence of canal irrigants and smear layer on the property of apical seal. Fourty-five canals from human teeth were randomly selected and divided into 5 groups according to the irrigants used in conjunction with instrumentation. The irrigants were RC-prep in combination with Naocl, Citric acid, Naocl, Naocl in combination with $H_2O_2$, and normal saline solution. After instrumention and dry the canal with paper point, the canals were obturated by lateral condensation of Zinc-oxide eugenol sealer and gutta percha cone. All the specimens were immersed in 2% methylene blue dye solution for 7 days and the depth of dye penetration into the canals was evaluated by macros cope. The following results were obtained. 1. All the canals experimented showed varying degree of dye penetration. 2. There was no significant difference in depth of dye penetration between the groups known to be effective and ineffective in the removal of the smear layer. 3. The canals irrigated with NaOCl alone showed the highest dye penetration and mean leakage was 7.7 mm. 4. In the canals irrigated with RC-prep in combination with Naocl and citric acid, the mean dye penetration was 5.5 mm and 4.8 mm respectively, and the canals irrigated with NaOCl in combination with $H_2O_2$ and normal saline solution revealed mean dye penetration of 3.9 mm.

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Experimental investigation of steel fiber effects on anti-penetration performance of self-compacting concrete

  • Jian Ma;Liang Bian;Jie Zhang;Kai Zhao;Huayan Yao;Yongliang Zhang
    • Advances in concrete construction
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    • v.16 no.2
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    • pp.119-126
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    • 2023
  • Steel fiber reinforced self-compacting concrete (SFRSCC) has good workability such as high flowability and good cohesiveness. The workability, compressive strength, splitting tensile strength, and anti-penetration characteristics of three kinds of SFRSCC were investigated in this paper. The fraction of steel fibers of the SFRSCC is 0.5%, 1.5% and 2.0% respectively. The results of the static tests show that the splitting tensile strength increases with the increase of fraction of steel fibers, while the compressive strength of 1.5% SFRSCC is lowest. It is demonstrated that the anti-penetration ability of 1.5% SFRSCC subjected to a velocity projectile (200-500 m/s) is better than 0.5% and 2.0% SFRSCC according to the experimental results. Considering the steel fiber effects, the existing formula is revised to predict penetration depth, and it is revealed that the revised predicted depth of penetration is in good agreement with the experimental results. The conclusion of this paper is helpful to the experimental investigations and engineering application.

THE EFFECT OF PRIMER ON PENETRATION OF SEALANT (치면열구전색제의 열구 침투에 primer의 효과)

  • Jeong, Hye-Seon;Lee, Jae-Ho;Choi, Hyung-Jun;Choi, Byung-Jai
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.2
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    • pp.416-426
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    • 1999
  • The objective of this study is to confirm the effect of dentine bonding primer application on penetration of sealant. Extracted permanent molars were used to compare penetration success rate of control group (sealant application only) and experimental groups (sealant application after applying the primers of $Scotchbond^{TM}$ Multi-Purpose system and $All-Bond^{(R)}$ 2 system). The following results were obtained: 1. The experimental groups using the primers showed increased sealant penetration success rate to the base of fissure when compared to control group but there was no statistically significant differences(p>0.05). 2. The depth, width and 'depth/width' value of fissure had statistically significant effect on sealant penetration success rate(p<0.05). 3. The penetration success rate decreased about 0.9 times as the depth of fissure increased every $25{\mu}m$, and increased about 1.1 times as the width of the fissure orifice increased every $25{\mu}m$ and decreased about 0.6 times as the 'depth/width' value increased every 1. From the above results, it can be concluded that assure morphology had a great effect on sealant penetration and for better penetration, use of dentine bonding primer can be helpful but it needs more study in clinical bases.

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A Study on the Color Granite Fabrication by Bias Enhancement Method (바이어스 인가 방식에 의한 컬러 화강석 제조에 관한 연구)

  • Park, Jong Kug;Shin, Hong-Jik;Choi, Won Seok;Han, Jae Chan
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.4
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    • pp.247-249
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    • 2016
  • In this study, we investigated the color change of the normal light gray granite as the high value color granite. By coating the metal catalyst liquid on the surface of granite stone, the metal particles were penetrated into the granite and the color of granite was changed permanently through the annealing treatment. To increase penetration depth into the granite, we used DC (direct current) bias. Two kinds of bias were used such as DC bias and pulse DC bias. And the penetration time was changed as 30 and 60 min. In all cases, the color granite were successfully obtained. Regardless of the catalyst reaction time, the penetration depth was increased by using the bias treatment. We obtained a penetration depth of 21 mm with the DC pulse bias during 60 min.

Pigment Analysis for Wall Paintings According to Verification of Penetration Depth for X-ray: Ssanggyesa Daeungjeon (Main Hall of Ssanggyesa Temple) in Nonsan (X-선 투과깊이 검증에 따른 벽화 안료의 정밀분석: 논산 쌍계사 대웅전)

  • Chun, Yu-Gun;Lee, Chan-Hee
    • Journal of Conservation Science
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    • v.27 no.3
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    • pp.269-276
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    • 2011
  • We have suggested effective P-XRF analysis method for pigment painting layer by calculating penetration depth of X-ray. This experiment calculated that X-ray generated from P-XRF was possible penetration until 1.17mm deep in the pigment painting. Based on the experimental results, analysis for eight color pigments on wall paintings in Ssanggyesa Main Hall, most pigments were painted traditional pigments. However pigments on recently restorated wall painting were used synthetic modern pigments.

Comparison of Modified Berggren Method with Numerical Method for the Frost Penetration Depth (수정 Berggren 법과 수치해석법에 의한 동결깊이 산정 비교)

  • Kim, Kwangjin;Kim, Youngchin;Lee, Daeyoung;Lee, Hayoung
    • Journal of the Korean GEO-environmental Society
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    • v.14 no.6
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    • pp.21-29
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    • 2013
  • This paper presents computed frost penetration depths for a number of cross sections of multilayered system including insulation. Results of Modified Berggren method were compared with those of numerical analysis which is based on finite element method with phase change. For the homogeneous single layer medium, Modified Berggren method gives almost the same results as finite element based numerical method. For the multilayered systems with insulation, Modified Berggren method shows, however, inaccurate results compared with FEM results. Therefore numerical solution based on finite element or finite difference should be used in place of Modified Beggren method to estimate the frost penetration depth for the layered medium with insulation.

The Distribution Frost Penetration Depth and Relationship between Frost Penetration and Freezing Index in South Korea (전국(全國) 동결(凍結)깊이 분포(分布)와 동결깊이 및 동결지수(凍結指數)와의 상관관계(相關關係))

  • Kim, Sang Kyu;Park, Sang Kil;Park, Bang Hun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.10 no.2
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    • pp.79-90
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    • 1990
  • The National Construction Research Institute of Korea has measured the depth of the frozen ground covering all the areas of South Korea during ten years ranging through 1980. The measurements were made for the frozen ground at random but intended for the most frost-susceptible soils. The soils of the frozen ground were sampled and then classifide into four groups according to the frost design soil classification system suggested by the Corps of Engineers of the United States. The contours of the maximum depth of the frost penetration are drawn on a map with data collected during the ten years. Also isolines of the design frezing index are shown on an another map using the metorological information of 1980-1989 and compared whth those in vestigated in 1980 by Highway Survey Team of the Ministry of Construction, Korea. It is known that the maximum depth of the frost penetration is related to freezing index values. An empirical formula expressing the relation is suggsted, in which the depth is proportional to the one-third power of the air freezing index values.

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A Study on the Depth of Frost Penetration in Korea (우리나라의 동결심도(凍結深度)에 관한 연구(研究))

  • Hong, Won Pyo;Kim, Myung Hwan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.8 no.2
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    • pp.147-154
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    • 1988
  • Korea has the ground which freezes in winter and melts in warmer seasons by turns. Therefore, in designing civil-structures or buildings on such ground, the depth of seasonal frost penetratio must be considered. In this paper, approximate contours of the maximum depth of frost penetration in Korea is presented. It was found that the maximum depth of frost penetration did not have the linear relationship to square root of the freezing index. In order to establish more reliable method to estimate the maximum depth of frost penetration, a new empirical equation is introduced. In the presented equation, the dry unit weight and water content of soil are considered in addition to the freezing index. And the equation is compared with other previous equations used so far.

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