Acta Geotechnica Slovenica最新文献_第3页

Determining the pile bearing capacity use of pda test results and neural networks 利用pda试验结果和神经网络确定桩的承载力

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2020-01-01 DOI: 10.18690/ACTAGEOTECHSLOV.17.2.34-45.2020

Saeed Ghaffarpour Jahrom, Mohammad Sharafuddin

{"title":"Determining the pile bearing capacity use of pda test results and neural networks","authors":"Saeed Ghaffarpour Jahrom, Mohammad Sharafuddin","doi":"10.18690/ACTAGEOTECHSLOV.17.2.34-45.2020","DOIUrl":"https://doi.org/10.18690/ACTAGEOTECHSLOV.17.2.34-45.2020","url":null,"abstract":"The dynamic loading or PDA test is one of the on-site experiments to estimate the bearing capacity of a pile. This test is based on the wave-propagation theory and can provide a good estimate of the bearing capacity of a pile as well as an assessment of the health of the pile. In this research, using the results of 100 dynamic loading tests carried out with different piles and projects, three types of artificial neural network (ANN) have been used to estimate the load. Initially, the perceptron multi-layer neural network was one of the most used neural networks. Subsequently, the neuro-fuzzy network is used in a combination of neuro-fuzzy networks and, at the end of the radial-based neural network, a successful network was used for non-linear problems. Between the different models of the neural network used by researchers, the multi-layered perceptron network has a better performance. However, other networks used have also proven successful. Finally, different models of the neural networks were compared and the network that has the best performance was identified in both phases. The models based on neural networks, unlike conventional behavioral models, do not explain how the input parameters affect the output. In this research, by analyzing the sensitivity to the optimal structure of the introduced models in each step, we have tried to partly answer this question. Also, the extraction and presentation of the relations governing a neural network model to the user is more reliable in the use of such models, which facilitates the application of such models in engineering works. In this research, four first indicators were used to evaluate and compare the models and structures.","PeriodicalId":50897,"journal":{"name":"Acta Geotechnica Slovenica","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67766459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical estimation of the one-dimensional consolidation behavior of clay 粘土一维固结特性的数值估计

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2020-01-01 DOI: 10.18690/10.18690/ACTAGEOTECHSLOV.17.2.16-25.2020

Firdevs Uysal, O. Sivrikaya

引用次数: 0

Investigation of soil displacements caused by the press-in process for close-ended model piles using an imaging technique 用成像技术研究封闭式模型桩压入过程引起的土体位移

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2020-01-01 DOI: 10.18690/10.18690/ACTAGEOTECHSLOV.17.2.2-15.2020

Ye Lu, Yun Jiang, Xiaoyong Wang

{"title":"Investigation of soil displacements caused by the press-in process for close-ended model piles using an imaging technique","authors":"Ye Lu, Yun Jiang, Xiaoyong Wang","doi":"10.18690/10.18690/ACTAGEOTECHSLOV.17.2.2-15.2020","DOIUrl":"https://doi.org/10.18690/10.18690/ACTAGEOTECHSLOV.17.2.2-15.2020","url":null,"abstract":"In recent years, installing piles using the press-in method has gained popularity in urban areas. However, pushing piles into the ground squeezes the surrounding soils and consequently causes a disturbance or even damage to the underground structures and facilities close by. In order to investigate the squeezing effect incurred by press-in piling, a series of model tests were performed. The soil displacement field was captured using a non-contact technique called digital image correlation (DIC), and the horizontal soil stresses were measured by mini pressure cells. Analyses of the soil displacement fields showed that the pile press-in process caused different soil displacement paths at different depths and locations. The development of horizontal soil stresses correlated well with the horizontal and vertical displacements. A thin disturbance layer could be observed along the pile-soil interface and it was about 7.4-11.1 D50 in thickness (D50, median particle size). At the end, the soil displacements caused by pushing the model pile with different pile shoes were analyzed and compared, and the analyses showed that a greater shoe angle resulted in greater disturbance to the surrounding soils. However, the influence of the pile shoe angle became less substantial with the increase of the pile penetration depth.","PeriodicalId":50897,"journal":{"name":"Acta Geotechnica Slovenica","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67766092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

The consolidation matrix and the consolidation circle 固结矩阵和固结圈

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2020-01-01 DOI: 10.18690/ACTAGEOTECHSLOV.17.2.56-64.2020

Houssam Khelalfa

{"title":"The consolidation matrix and the consolidation circle","authors":"Houssam Khelalfa","doi":"10.18690/ACTAGEOTECHSLOV.17.2.56-64.2020","DOIUrl":"https://doi.org/10.18690/ACTAGEOTECHSLOV.17.2.56-64.2020","url":null,"abstract":"In geotechnical engineering, the consolidation and settlement of structures are among the major problems an engineer must deal with. An appropriate estimation of a soil’s settlement is of significant importance, since it directly influences the performance of buildings and infrastructures that are built on soil.The compressibility characteristics of soils form one of the most important parameters required in the design of foundations. The compressibility behaviour of soils islargely dependent on the compression index, the properties and the parameters of the soil. A number of empirical correlations have been developed in the literature that aresupposedto connect the compression index to other soil parameters. The main objectives of this research were to study the relationships between the compression index (Cc) and the swelling index (Cs), and to investigate the effects of the natural void ratio (e0) and the over-consolidation ratio (OCR) on Cc and Cs, in order to combine them with the pre-compression stress (Pc), the consolidation duration (Tc) and the settlement (Su).Consequently, aconsolidation matrix and a consolidation circle are proposed, which gives us a new method and model to facilitate the calculations of the parameters involved in the soil consolidation, so as to summarize the consolidation phenomenon.","PeriodicalId":50897,"journal":{"name":"Acta Geotechnica Slovenica","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67766522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of grain size distribution on the maximum and minimum void ratios of granular soils 粒径分布对颗粒土最大、最小空隙比的影响

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2020-01-01 DOI: 10.18690/ACTAGEOTECHSLOV.17.2.26-33.2020

J. Duque, William Mario Fuentes Lacouture, Jorge Andres Barros Ayala

引用次数: 2

Effects of grain shape on the standard penetration test and particle packing 晶粒形状对标准渗透试验和颗粒堆积的影响

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2020-01-01 DOI: 10.18690/ACTAGEOTECHSLOV.17.2.65-75.2020

Ender Başarı, Gürkan Özden

{"title":"Effects of grain shape on the standard penetration test and particle packing","authors":"Ender Başarı, Gürkan Özden","doi":"10.18690/ACTAGEOTECHSLOV.17.2.65-75.2020","DOIUrl":"https://doi.org/10.18690/ACTAGEOTECHSLOV.17.2.65-75.2020","url":null,"abstract":"Coarse soils can contain flaky grains in addition to rounded or angular grains, along with a varying fines content. Depending on the regional geology, however, the mica grain content can be remarkable, reaching 30 % or higher. Therefore, it is reasonable to expect that mica grains would affect the soil behaviour. In this study, soils of a delta deposit that are known to involve mica grains were examined. The river sand was considered as the host material and the mica grain contents were determined by means of the flotation technique. A correlation between the mica content as found using the flotation technique and XRD count numbers obtained using an X-ray diffraction test method for each soil sample was established. The standard penetration test (SPT) blow counts from various boreholes were interpreted from the mica content’s influence point of view. The results showed that the mica grains would reduce the SPT resistance at certain fines-content, host-sand, mica-grain combinations. The reduction in the SPT resistance as a result of the presence of mica grains might reach eight units at depths close to the ground surface. This influence is expressed by means of a dimensionless parameter (MCef); however, it diminished with an increasing effective stress and fines content. The findings of the present study show that the influence of particle shape on the overall soil behaviour deserves further study.","PeriodicalId":50897,"journal":{"name":"Acta Geotechnica Slovenica","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67766544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A numerical study of reinforced embankments supported by encased floating columns 封闭浮柱支撑加固路堤的数值研究

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2019-01-01 DOI: 10.18690/actageotechslov.16.2.25-38.2019

M. R. Kahyaoğlu, M. Vaníček

{"title":"A numerical study of reinforced embankments supported by encased floating columns","authors":"M. R. Kahyaoğlu, M. Vaníček","doi":"10.18690/actageotechslov.16.2.25-38.2019","DOIUrl":"https://doi.org/10.18690/actageotechslov.16.2.25-38.2019","url":null,"abstract":"This paper presents a three-dimensional, finite-element, parametric study of a base-reinforced embankment supported by encased floating columns on soft soil. A 3D numerical model is made to study the effects of geogrid basal reinforcement and geotextile encasement on the displacement behavior of the columns. The numerical model was initially verified using measured data from a real case study. Then, parametric studies were subsequently performed, considering the effect of the encasement stiffness, the basal reinforcement stiffness and the embankment fill height, together with an examination of the effective length of the encasement. The results from this parametric study are presented here in the form of comparative graphs. The objective of this paper is to present the behavior of the embankment on floating encased columns after the soft soil consolidation for different embankment heights, basal reinforcement and column-encasement stiffnesses. Mehmet Rifat Kahyaoğlu (corresponding author) Muğla Sitki Kocman University, Engineering Faculty, Department of Civil Engineering 48000, Mentese-Muğla, Turkey E-mail: rkahyaoglu@mu.edu.tr Martin Vaníček Geosyntetika Ltd. N.Tesla str. 3, 160 00 Praha 6, The Czech Republic E-mail: mvanicek@geosyntetika.cz","PeriodicalId":50897,"journal":{"name":"Acta Geotechnica Slovenica","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67766774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Research on a numerical model of real mesostructures in the non-shear zone of clay 黏土非剪切带细观结构数值模型研究

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2019-01-01 DOI: 10.18690/actageotechslov.16.2.66-76.2019

Wei Wang, B. Zhao, Liwu Yu, Deheng Zang

{"title":"Research on a numerical model of real mesostructures in the non-shear zone of clay","authors":"Wei Wang, B. Zhao, Liwu Yu, Deheng Zang","doi":"10.18690/actageotechslov.16.2.66-76.2019","DOIUrl":"https://doi.org/10.18690/actageotechslov.16.2.66-76.2019","url":null,"abstract":"The conventional numerical simulations of rock and soil are mainly concerned with the macroscopic continuous model or the pseudo-microscopic model established using the discrete-element method (DEM). However, these adopted models are not completely consistent with actual soil samples. To explore the evolution law of the internal stresses of soil samples from the mesoscopic perspective, we proposed an image-finite-element method for studying the deflection angles and the shear stresses at four points in the non-shear zone of clay with real mesostructures. The approach allowed for a realistic distribution of the pore structures and avoided any virtualization, thereby significantly improving the veracity of the mesoscopic model. It worked by using a microscopic lens and a charge-coupled device (CCD) to capture the two-dimensional (2D) meso image in the non-shear zone, and then convert this digital image into a vector image recognized by the finite-element software (ABAQUS) through image-processing techniques, and import it into a numerical model, and then carry out a numerical calculation. For the purposes of performing a","PeriodicalId":50897,"journal":{"name":"Acta Geotechnica Slovenica","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67766911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Two- and three-dimensional analyses of the effect of pile spacing in piled-raft foundations 桩筏基础中桩间距影响的二维和三维分析

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2019-01-01 DOI: 10.18690/actageotechslov.16.1.43-52.2019

O. Sivrikaya, Gürkan A. Yazıcı

引用次数: 2

Determining the position of points on geologically unstable land with geodetic monitoring 利用大地测量监测确定地质不稳定地上点的位置

IF 0.6 4区工程技术

Acta Geotechnica Slovenica Pub Date : 2019-01-01 DOI: 10.18690/ACTAGEOTECHSLOV.16.1.2-12.2019

B. Kovačič

引用次数: 0