{"title":"A Study on Development of Portable Concrete Crack Measurement Device Using Image Processing Technique and Laser Sensors","authors":"S. Seo, S. Ohn, Dong-Hyun Kim, K. Kwak, M. Chung","doi":"10.12814/JKGSS.2020.19.4.041","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.4.041","url":null,"abstract":"","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77664841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of Application Cases and Evaluation of Effectiveness on Portable Dynamic Cone Penetration Test (DCPT) to Identify the Deterioration Cause of Damaged Reinforced Earth Walls","authors":"K. Lee, S. Cho","doi":"10.12814/JKGSS.2020.19.4.095","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.4.095","url":null,"abstract":"In this study, a total of six site cases were reviewed to assess the site applicability of portable dynamic cone penetration test (DCPT) by identifying the cause of damage to the damaged reinforced earth wall using portable dynamic cone penetration test. An improved dynamic concrete penetration tester was used at the site to enable ground surveys of more than 6 meters. The test results were compared with the results of the standard penetration test (SPT) and the correlation was analyzed. Through the analysis of various field application cases, it was found that portable dynamic cone penetration test was very convenient to apply at the site of the damaged reinforced earth wall, and DCPT could play a major role in identifying the cause of damage and verifying stability of the retaining wall by continuously identifying the ground strength. In addition, it was found that the results of the dynamic cone penetration test and the standard penetration test showed a correlation of N≒(1/3~2/3)・Nd in sandy soil.","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86610066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Study on Correlation between Volume Conversion Factor and Apparent Density of Wastes Buried in Landfill","authors":"Jinwoo Cho","doi":"10.12814/JKGSS.2020.19.4.033","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.4.033","url":null,"abstract":"It is now common to find the wastes buried in the past during the excavation process of soil for large scale housing and land development. Without proper treatment of the wastes environmentally, the excavation process is no longer able to proceed, and an action plan should be provided to treat the wastes with environmental and economic viability. In the study, the relationship between the apparent density of the wastes and the volume conversion factor, which is the basis in the estimation of waste treatment cost was investigated. From 10 sampling points of a landfill site, wastes were sampled, analyzed for physical characteristics, and the apparent density of mixed and sorted waste was assessed. Applying the empirical formula, and the formula we suggested here, the volume conversion factors were compared with that measured directly in the field using dump truck and excavator. Obviously there was a close relationship among the volume conversion factors resulting from the empirical formula, the formula we suggested and that measured in the field.","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80496991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Experimental Study on Soft Ground with DCM Column","authors":"G. Hong","doi":"10.12814/JKGSS.2020.19.3.035","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.3.035","url":null,"abstract":"This study described the result of laboratory model tests, in order to compare the improvement effect of the DCM column installed on the soft ground according to DCM column type. In the laboratory model test, the non-reinforced type and the 3 types of DCM column were applied, and the behavior (settlement, lateral flow) of soft ground was evaluated under the surcharge load condition for each type. The settlement evaluation result showed that the settlement of soft ground without DCM column occurred rapidly under the low load condition, but the settlement of the soft ground with the DCM column had relatively small settlement. The evaluation result of lateral flow in the soft ground showed that the soft ground with DCM column had lower lateral displacement than the soft ground without DCM column. Especially, the lateral displacement under the same load condition decreased in the order of pile type, wall type, and grid type. Therefore, it confirmed that the improvement effect of soft ground was excellent when the DCM of grid type was applied for settlement and lateral flow.","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91091645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Woo-Yeol Yang, T. Hwang, Bumjoo Kim, Seong-Bak Park, K. Lee
{"title":"Evaluation of Lateral Subgrade Reaction Coefficient Considering Empirical Equation and Horizontal Behavior Range of Large Diameter Drilled Shaft","authors":"Woo-Yeol Yang, T. Hwang, Bumjoo Kim, Seong-Bak Park, K. Lee","doi":"10.12814/JKGSS.2020.19.2.001","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.2.001","url":null,"abstract":"The lateral bearing characteristics of large diameter drilled shaft depend greatly on the stiffness of the pile, horizontal subgrade reaction of adjacent ground. In particular, the empirical evaluation results of the horizontal subgrade reaction coefficient which are widely used in pile design are very important factors in evaluating the lateral bearing capacity of drilled shaft because the difference in bearing capacity depends on the estimated result. Nevertheless, the evaluation of the horizontal subgrade reaction coefficient on the large diameter drilled shaft is insufficient. In addition, although the range of influence and the location of the maximum moment which is the weaken zone on the pile may be correlated and relationship of these are major consideration in determining the reinforced zone of drilled shaft, the previous studies have not been evaluated it. In this study, the field test and nonlinear analysis of large diameter drilled shaft were performed to evaluate the horizontal subgrade reaction coefficient and to investigate the relationship between the influence range 1/ of the pile and the location of the maximum moment zm. In the result, the lateral bearing capacity of drilled shaft showed a difference in results by about 190% according to the empirical equation on the horizontal subgrade reaction coefficient. And the relationship between the influence range of the pile and the location of the maximum moment was evaluated as a linear relationship depending on the soil density.","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90396555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Acid Rock Drainage Generation Capacity of Tertiary Mudstone in Pohang Basin","authors":"In-Woo Baek, J. Kim, Young-Suk Song, Taehyung Kim","doi":"10.12814/JKGSS.2020.19.2.023","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.2.023","url":null,"abstract":"This study determines the basic properties and acid rock drainage generation capacity of Pohang tertiary mudstone through laboratory experiments. According to X-ray fluorescence (XRF) analysis results, the mudstone of this area mostly comprised of with a proportion of approximately 60%, followed in order by and . As such, it is clear that there is an abundance of aluminosilicates with a high probability of generating acid rock drainage. The XRD analysis showed that the mudstone contains pyrite (), it is highly likely to generate acid rock drainage, and inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis results showed that the mudstone samples contained a high amount of ions. As a result of anion analysis measured by ion chromatography (IC), all mudstone samples were measured to have high concentrations. According to elemental analysis, the total sulfur (S) content was high, which in turn indicates a high risk of acid rock drainage generation reflected by a maximum potential acidity (MPA) higher than 1%. All in all, although there were slight deviations between the tertiary mudstone samples, overall, the samples exhibited high acid rock drainage generation capacities.","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73109275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hoyeon Kim, Yong Jin, Yonghee Lee, H. Kim, Daehyeon Kim
{"title":"Dynamic Response Characteristics of Embankment Model for Various Slope Angles","authors":"Hoyeon Kim, Yong Jin, Yonghee Lee, H. Kim, Daehyeon Kim","doi":"10.12814/JKGSS.2020.19.2.035","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.2.035","url":null,"abstract":"In this study, the dynamic response characteristics of the embankment model were analyzed using shaking table experiments. Laminar shear box was used to minimize the boundary effect of the model. The ratio of the vertical length to horizontal length of the slopes were 1:1, 1:1.5, and 1:2. The sensor array which is consist of 12 accelerometers was used to measure acceleration time-histories at each location of the slope model. The dynamic response characteristics of the models were analyzed for sine wave, sinesweep wave, and artificial earthquake wave in this study. The experimental results show that the dynamic response of the embankment model is increased with the slope angle. Furthermore, the experimental setup used in this study was verified with the comparative analysis between experimental results and 1-D analytical simulation on the flat ground model.","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72866052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Study on the Behavior Characteristics of Large Deep Foundations","authors":"Choongsuk. Park, Kwang-Min Jung","doi":"10.12814/JKGSS.2020.19.1.083","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.1.083","url":null,"abstract":"","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74983669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Prediction of Track Quality Index (TQI) Using Vehicle Acceleration Data based on Machine Learning","authors":"C. Choi, Hunki Kim, Young Cheul Kim, Sang-su Kim","doi":"10.12814/JKGSS.2020.19.1.045","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.1.045","url":null,"abstract":"There is an increasing tendency to try to make predictive analysis using measurement data based on machine learning techniques in the railway industries. In this paper, it was predicted that Track quality index (TQI) using vehicle acceleration data based on the machine learning method. The XGB (XGBoost) was the most accurate with 85% in the all data sets. Unlike the SVM model with a single algorithm, the RF and XGB model with a ensemble system were considered to be good at the prediction performance. In the case of the Surface TQI, it is shown that the acceleration of the z axis is highly related to the vertical direction and is in good agreement with the previous studies. Therefore, it is appropriate to apply the model with the ensemble algorithm to predict the track quality index using the vehicle vibration acceleration data because the accuracy may vary depending on the applied model in the machine learning methods.","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81121271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Seung-Jae Yang, Kimun Park, Hyung-Yeol Park, Kyung-Jin Yang, Chan-kee Kim
{"title":"A Study on the Behaviour of Baekma River Sands Using Elasto-Plastic Hyperbolic Model","authors":"Seung-Jae Yang, Kimun Park, Hyung-Yeol Park, Kyung-Jin Yang, Chan-kee Kim","doi":"10.12814/JKGSS.2020.19.1.093","DOIUrl":"https://doi.org/10.12814/JKGSS.2020.19.1.093","url":null,"abstract":"In order to predict the nonlinear behaviour of the soil, the elasto-plastic hyperbolic model was selected, which was considered to be relatively simple and highly predictable. The soil parameter determination and the behavior analysis program were developed by formalizing the functions related to the constitutive model. Each soil parameter was determined from the results of the drained triaxial compression tests of Baekma river sand with the change of relative density. The stress-strain behavior was predicted using the soil parameters determined under each condition. As a result, the deviator stress for the axial strain is verified to have a good match between the measured value and predicted value at each relative density. In the relationship between the volumetric stain and the axial strain, when the relative density is loose, the measured value and predicted value tend to match, and when relative density is dense, the predicted value of the volumetric strain appears somewhat smaller than the measured value due to the limitation of the constitutive model. 요 지 흙의 비선형적 거동특성을 예측하기 위해 비교적 간편하고 예측의 정도가 높은 것으로 평가되는 탄・소성 쌍곡선모델을 선정하 였다. 모델의 특성을 알아보기 위해 구성모델에 관련된 함수를 정식화하여 토질매개변수 결정 및 거동해석 프로그램을 개발하 였다. 상대밀도 변화에 따른 백마강모래의 배수삼축압축시험 결과로부터 각각의 토질매개변수를 결정하였고 상대밀도에 따른 토질매개변수의 변화 특성을 분석하였으며 각각의 조건에서 결정된 토질매개변수를 이용하여 응력-변형률 거동을 예측하였다. 그 결과 축변형률에 대한 축차응력은 각각의 상대밀도에서 측정치와 예측치가 양호하게 일치하는 것을 확인하였고 축변형률 에 대한 체적변형률의 관계에서 상대밀도가 작은 경우는 측정치와 예측치가 일치하는 경향을 보이나 상대밀도가 큰 경우에는 구성모델의 한계로 인해 체적변형률의 예측치가 측정치보다 다소 작게 나타나는 것을 확인 하였다.","PeriodicalId":42164,"journal":{"name":"Journal of the Korean Geosynthetic Society","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83803656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}