Journal of JSCE最新文献

EARTHQUAKE-TSUNAMI INTERACTION DIAGRAM CONSIDERING TWO DIFFERENT LIMIT STATES 考虑两种不同极限状态的地震-海啸相互作用图

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.23-18188

Thanisorn SRIKULRUANGROJ, Atsushi MIKAMI

引用次数: 0

INVESTIGATION OF TSUNAMI INDUCED LANDWARD SCOUR WITH XBEACH 海啸引起的xbeach向陆地冲刷的研究

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.23-18089

Mustarakh GELFI, Takayuki SUZUKI

{"title":"INVESTIGATION OF TSUNAMI INDUCED LANDWARD SCOUR WITH XBEACH","authors":"Mustarakh GELFI, Takayuki SUZUKI","doi":"10.2208/journalofjsce.23-18089","DOIUrl":"https://doi.org/10.2208/journalofjsce.23-18089","url":null,"abstract":"XBeach is a numerical model for simulating coastal processes, including beach morphodynamics, dune evolution, and overwash processes. It is designed to simulate the response of the beach to various environmental factors, including waves. XBeach uses advanced numerical algorithms to solve the equations of motion and sediment transport and is capable of modeling the complex interactions between the ocean and the beach. Landward scour is the sediment’s hole behind the structure which is induced by overflowing flow during the extreme event, such as tsunamis and storms, which have high water depth and large velocity flow. This research is about modeling of landward scour phenomenon. The simulation results were compared against experimental results. This study shows that XBeach can model the morphodynamics shape of the scour hole. However, the scour depth as also suggested by other researchers for extreme overflowing setting is overestimated. Hydrodynamics parameters (water level) can be reproduced by the model with good agreement against the experiment although simulated flow velocity is slightly overestimated. It was also found that in a very short time scale phenomenon, as in the landward scour experiment, the model is sensitive to governing equation of sediment transport. An attempt to enhance the result by implementing artificial erosion limiter by using soil dilatancy improves the results, especially for erosion volume (Verr).","PeriodicalId":311811,"journal":{"name":"Journal of JSCE","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135911444","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}

引用次数: 0

APPLICABILITY OF A TUNNEL DEFORMATION ESTIMATION FROM A POINT CLOUD ADOPTING ELLIPTIC FOURIER ANALYSIS 椭圆傅里叶分析对点云隧道变形估计的适用性

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.22-00351

Naotoshi YASUDA, Ying CUI

引用次数: 0

EVALUATION OF THE UPSTREAM WATER LEVEL OF THE FLOW OVER FINITE-LENGTH WEIRS WITH RECTANGULAR CROSS-SECTION IN THE FLOW DIRECTION 流向矩形截面有限长堰上游水位的评价

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.23-00138

Kesayoshi HADANO, Kenji TATARA, Hiroyuki NAGANO, Kazumitsu MURAOKA

引用次数: 0

EFFECT OF SEDIMENT SIZE ON SANDBAR MORPHOLOGY IN DIFFERENT COMPACTION CONDITIONS 不同压实条件下泥沙粒度对沙洲形态的影响

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.23-18100

Md Shofiqul ISLAM, Takayuki SUZUKI

{"title":"EFFECT OF SEDIMENT SIZE ON SANDBAR MORPHOLOGY IN DIFFERENT COMPACTION CONDITIONS","authors":"Md Shofiqul ISLAM, Takayuki SUZUKI","doi":"10.2208/journalofjsce.23-18100","DOIUrl":"https://doi.org/10.2208/journalofjsce.23-18100","url":null,"abstract":"This study presents the effect of sediment size on the morphological change of a sandbar under loose and medium-dense compaction. An artificial cross-shore beach profile was designed with a small-scale sandbar on the offshore side of a 2D wave flume. A total of 12 regular wave cases were tested on two different sandbars setup using medium sand (D50 = 0.33 mm) and very fine sand (D50 = 0.08 mm). Experimental results revealed that very fine sand was more susceptible to erosion than medium sand in the mechanism of wave breaking to impinging. The maximum erosion zone for medium and very fine sand was found at the offshore sharp edge of the sandbar and at the impinging point, respectively. In loose compaction, a strong inverse correlation (R2 = 0.80) was found between the net erosion volume and wave steepness for the medium sand, whereas a sharp peak of net erosion volume existed at the medium wave steepness in very fine sand. In medium-dense compaction of very fine sand, the reduction of net erosion volume was 67 %, 57 %, and 82 % at low, medium, and high wave steepness, respectively. At the middle depth of the sandbar, very fine sand yielded an average increase in shear strength that was five times higher than medium sand. At this depth, a strong inverse correlation (R2 = 0.84) was established between the change in average shear strength and wave steepness under loose compaction of medium sand, however, similar to net erosion volume, a sharp peak was found at the medium wave steepness of very fine sand. Furthermore, datasets assessed in the laboratory would be useful for numerical simulation.","PeriodicalId":311811,"journal":{"name":"Journal of JSCE","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135911253","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}

引用次数: 0

APPLYING ARTIFICIAL NEURAL NETWORKS FOR PREDICTING BEACH VULNERABILITY TO STORM-INDUCED EROSION 应用人工神经网络预测海滩对风暴侵蚀的脆弱性

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.23-18101

Salika THILAKARATHNE, Takayuki SUZUKI, Martin MÄLL

{"title":"APPLYING ARTIFICIAL NEURAL NETWORKS FOR PREDICTING BEACH VULNERABILITY TO STORM-INDUCED EROSION","authors":"Salika THILAKARATHNE, Takayuki SUZUKI, Martin MÄLL","doi":"10.2208/journalofjsce.23-18101","DOIUrl":"https://doi.org/10.2208/journalofjsce.23-18101","url":null,"abstract":"This study investigates the potential of Artificial Neural Networks (ANN) in predicting beach vulnerability to storm-induced erosion. Long-term morphology and hydrodynamic data (24 years) from Hasaki beach in Japan were used to identify storm events and quantify beach erosion. First, to compare the performance of an ANN model with a Multiple Linear Regression (MLR) model in predicting the shoreline change (dSL) during storms, we used initial shoreline position, storm power, maximum surge, and beach slope as input variables. Next, the model predictions of the dSL were utilized to quantify the beach vulnerability on a scale of 1 to 5, resulting in the creation of the Beach Vulnerability Index: BVIANN for the ANN model and BVIMLR for the MLR model. While MLR performed well for short-term beach erosion predictions (8 years) as Thilakarathne et al. (2022) showed, our results indicate that it was less effective when using long-term storm data. In contrast, ANN demonstrated superior performance, resulting in more accurate predictions of beach vulnerability. Specifically, the Mean Absolute Errors for BVIMLR were 1.33, 0.83, 0.78, 0.90, and 1.07, while for BVIANN were 1.00, 0.20, 0.69, 1.05, and 0.57 for indexes 1-5, respectively. The ANN model also achieved higher R2 Scores for both training (0.65) and testing (0.62) data in predicting dSL, compared to the MLR model (0.26 on training and 0.35 on testing). The study findings suggest that using ANN or other Machine Learning (ML)-based algorithms for coastal/beach vulnerability studies has significant potential for capturing and representing the dynamic nature of beach morphology changes with increased accuracy. The study's contribution adds to the growing body of research on using ANN and ML algorithms for predicting coastal morphology changes and beach vulnerability, highlighting the potential of these methods for future coastal engineering applications.","PeriodicalId":311811,"journal":{"name":"Journal of JSCE","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135913879","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}

引用次数: 0

A NOVEL PARTICLE SIZE CLASSIFICATION-BASED METHOD FOR ANALYZING TOTAL MERCURY CONCENTRATION DISTRIBUTION OF SEDIMENT IN THE YATSUSHIRO SEA 基于粒径分类的矢津海沉积物总汞浓度分布分析新方法

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.23-18037

Baixin CHI, Akito MATSUYAMA, Shinichiro YANO, Michiaki KINDAICHIA, Yoko TANIGUCHI

引用次数: 0

DEGRADATION AND MASS LOSS OF JAPANESE CEDAR CYLINDRICAL PILES BURIED FOR 10 YEARS WITH THEIR HEADS AT THE GROUND SURFACE 头埋10年的杉木圆柱桩的退化和质量损失

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.22-00315

Mario TONOSAKI, Atsunori NUMATA, Shigeru TAKAHARA, Kana YAMASHITA, Yoshitaka KUBOJIMA

{"title":"DEGRADATION AND MASS LOSS OF JAPANESE CEDAR CYLINDRICAL PILES BURIED FOR 10 YEARS WITH THEIR HEADS AT THE GROUND SURFACE","authors":"Mario TONOSAKI, Atsunori NUMATA, Shigeru TAKAHARA, Kana YAMASHITA, Yoshitaka KUBOJIMA","doi":"10.2208/journalofjsce.22-00315","DOIUrl":"https://doi.org/10.2208/journalofjsce.22-00315","url":null,"abstract":"Timber piles for ground improvement have many potential applications, and increasing carbon storage by expanding their usage is expected to contribute to net-zero greenhouse gas emissions by 2050. For this contribution to be reported by the Government of Japan, the rate of mass loss of underground wood must be estimated quantitatively; however, the rate of mass loss is currently unknown. In this paper, a study was performed of Japanese cedar cylindrical piles that were excavated after being buried with their heads at the ground surface for about 10 years in the Inashiki plateau, Japan. The rate of mass loss was analyzed, assuming that no wood decay occurred at depths below the lower limit of the groundwater level. The part of the piles in the range of groundwater fluctuation did not have recognizable mass loss. However, at depths above the upper limit of the groundwater level, the half-life of the mass loss of the parts of the piles where the outer peripheral shape remained was about 50 years, and that of the parts with cross-sectional loss was less than about 10 years.","PeriodicalId":311811,"journal":{"name":"Journal of JSCE","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135056666","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}

引用次数: 0

CORRECTION OF APPLIED EQUATIONS USED TO ASSESS THE AMPLIFICATION BETWEEN OFFSHORE AND COASTAL TSUNAMI HEIGHTS 修正用于评估近海和沿海海啸高度放大的应用方程

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.23-17036

Yutaka HAYASHI

引用次数: 0

VERTICAL DISTRIBUTION OF MERCURY IN BOTTOM SEDIMENTS AND PARTICLE SIZE EFFECT ON MIGRATION OF MERCURY-CONTAINING SEDIMENTS IN THE YATSUSHIRO SEA 海底沉积物中汞的垂直分布及粒径对含汞沉积物迁移的影响

Journal of JSCE Pub Date : 2023-01-01 DOI: 10.2208/journalofjsce.23-17139

Baixin CHI, Shinichiro YANO, Akito MATSUYAMA, Lin HAO

引用次数: 0