Techno Press
Tp_Editing System.E (TES.E)
Login Search
You logged in as...

gae
 
CONTENTS
Volume 43, Number 2, October25 2025
 

Abstract
Natural geotextiles have been increasing instead of synthetic geotextiles used in various geotechnical engineering applications because they are more environmentally friendly. In this study, a new type of geotextile called "Geo-Hemptex" is produced from hemp fibers for the first time that may be an alternative to synthetic and natural geotextiles. Unconsolidated-Undrained (UU) and interface shear box tests were conducted to determine the interaction between Geo-Hemptex and granular soil. Geo-Hemptex was placed in one and two layers during UU tests, and three different confining pressures were applied during tests. Interface shear box tests were conducted under three different normal stresses to determine the interface characteristics between Geo-Hemptex and granular soil. All tests were also carried out using synthetic woven and non-woven geotextiles to compare with Geo-Hemptex. UU tests were modelled using the finite element method. All geotextiles provided approximately similar results in interface shear strength. However, higher adhesion was determined for Geo-Hemptex compared to synthetic woven geotextile. Geotextile placement, axial stiffness of geotextile, and interface strength influenced the UU test results. The synthetic woven geotextile yielded higher strength in the case of single-layer orientation. In contrast, Geo-Hemptex and woven synthetic geotextiles resulted in similar strength increases in the case of double layer orientation. The results of this study demonstrate that Geo-Hemptex can be used as an alternative to synthetic geotextiles, reducing greenhouse gas emissions and synthetic residues in the soil, thus providing more environmentally friendly solutions to geotechnical engineering problems.

Key Words
geotextile; hemp; reinforcement; shear strength; triaxial test

Address
Eren Bayrakci: Vocational School of Transportation, Eskişehir Technical University, Eskişehir, Turkey
Eren Balaba and Mehmet İnanc Onur Faculty of Engineering, Department of Civil Engineering, Eskişehir Technical University, Eskisehir, Turkey
Yücel Güney: School for the Handicapped, Anadolu University, Eskişehir, Turkey
Yekta Karaduman: Department of Materials and Energy, Hemp Research Institute, Yozgat Bozok University, 66100, Yozgat, Turkey

Abstract
Suction caisson foundations are frequently used to moor offshore structures in the oil drilling and wind power generation industries. Though artificial neural network (ANN) models have been successfully applied to predict pile foundation capacity, the considerable differences between the characteristics of pile and suction caisson foundations imply that an ANN model trained using data from the former cannot be applied to predict the capacity of the latter. This study accordingly employed suction caisson foundation data to develop an ANN capable of accurately predicting the capacity of such foundations. The early stopping and model checkpoint techniques were applied to prevent overfitting by saving the immediately prior optimal weight. To obtain the optimal hyperparameter conditions efficiently, a Bayesian optimization algorithm was employed, which significantly reduced the optimization time. This algorithm produced four hyperparameter combinations that exhibited excellent performance; these were each used to train the ANN 500 times, thereby accounting for the uncertainty owing to randomly assigned initial weights. The proposed ANN was subsequently developed using two approaches: parameter analysis and optimization. The parameter analysis determined that the optimal number of network parameters for the selected hyperparameter combinations was 7,638, which was within the 500-650,000 range determined by a general analysis. The verification root mean square error(RMSE) of the ANN model developed using the optimization process was 8.88 with a coefficient of determination of 0.9998. Notably, because suction caisson foundation data have characteristics consistent with general geotechnical engineering practices, the optimal network parameter range and optimization method employed in this study to develop the ANN can be used with other data obtained in the geotechnical field.

Key Words
artificial neural network; network parameter; optimization; overfitting; suction caisson foundation

Address
Jaehyeok Han, Uichan Lee and Jongwon Jung: School of Civil Engineering, Chungbuk National University, Republic of Korea
Jaehun Ahn: Department of Civil and Environmental Engineering, Pusan National University, Republic of Korea
Jongmuk Won: Department of Civil Urban, Earth, and Environmental Engineering,
Ulsan National Institute of Science and Technology, Republic of Korea
Nhat-Duc Hoang: Institute of Research and Development, Duy Tan University, Da Nang, 550000, Vietnam;
Faculty of Civil Engineering, Duy Tan University, Da Nang, 550000, Vietnam

Abstract
The bearing capacity of foundations is one of the most important issues that have always attracted the attention of researchers and geotechnical engineers. In this article, the failure envelope of square footings resting on cohesive-frictional soils was investigated considering the simultaneous application of vertical, horizontal, and moment loads using finite element simulations. The effect of various factors such as soil internal friction angle, cohesion, modulus of elasticity, Poisson's ratio, unit weight and the failure criterion along with the groundwater table, the dimensions and the embedment depth of the footing were investigated. The results show that the soil friction angle has a greater effect on the size of the failure envelope than the soil cohesion. Moreover, the soil modulus of elasticity, Poisson's ratio, unit weight, and the groundwater table, have a minor effect on the size of the failure envelope compared to the footing embedment depth. By moving the footing from the ground surface to a depth equal to three times the footing width, the failure envelope enlarges more than seven times of its initial size.

Key Words
cohesive-frictional soil; combined loading; failure envelope; finite element method; square footing

Address
Amirreza Sadeghi and Meysam Imani: Geotechnical Engineering Group, Amirkabir University of Technology, Garmsar Campus, Iran

Abstract
The geotechnical behavior of varved clays in cold regions remains inadequately understood despite their widespread occurrence. This study addresses this gap by investigating the behavior of homogeneous and reconstituted varved clay samples through Unconfined Compressive Strength (UCS) testing. Homogeneous samples consist of Red Soil (RS) and Black Soil (BS), while reconstituted varved clays are prepared by layering RS and BS in configurations of 2, 4, 8, and 16 layers. UCS tests are conducted at displacement rates of 1.25, 0.24, and 0.024 mm/min, hypothesized to simulate the velocity of glacial override on soils. Samples are prepared at five moisture contents ranging from 0.8 to 1.2 OMC. Results indicate that as moisture content decreases below OMC, undrained shear strength increases for all samples, accompanied by a reduction in strain, while the opposite trend is observed for samples on the wet side of OMC. For reconstituted varved clays, undrained shear strength increases as number of laminae rises from 2 to 8, but decreases in the 16-laminae sample, which suggests a threshold exists for the number of laminae beyond which strength reduces. Displacement rate significantly influences failure modes and patterns, with samples exhibiting more ductile behavior at lower displacement rates and higher moisture contents.

Key Words
displacement rate; moisture content; reconstituted varve laminae; unconfined compressive strength test; undrained shear strength

Address
Deepali Anand, Arindam Dey and K. Ravi: Department of Civil Engineering, Indian Institute of Technology Guwahati, Amingaon, North Guwahati,
Guwahati, Assam 781039, India

Abstract
Offshore monopile foundations are subjected to combined loading from waves, wind, and operational forces, which progressively degrade the surrounding soil and threaten long-term stability. Conventional approaches, such as increasing pile size or incorporating steel fins, offer enhanced stiffness but remain limited in improving resistance to cumulative lateral deformation. To address these challenges, a bio-inspired design mimicking the frictional anisotropy of snake ventral skin is proposed to enhance shaft resistance through directionally textured pile surfaces. This study investigates the long-term behavior of offshore monopile foundation equipped with snakeskin-inspired surface geometries under repetitive lateral loading. A semi-empirical numerical scheme is employed to extract stress and strains at the first cycle using the Modified Cam Clay model, and to track the progressive plastic deformation during repetitive loading using the polynomial-type accumulation function that includes volumetric strain, shear strain, and stress obliquity. Parametric analyses are performed to evaluate the influence of scale geometry (height and length) and installation orientation (cranial vs. caudal) on performance of snakeskin-inspired pile. The results show that greater scale height and shorter scale length (particularly under cranial installation) improve lateral resistance and limit displacement accumulation by enhancing load transfer efficiency. Deviatoric stress contours reveal a coupled mechanism where early-stage strain hardening transitions into localized softening, accompanied by progressive stress redistribution and displacement accumulation.

Key Words
offshore monopile foundation; repetitive lateral load; scale geometry; semi-empirical numerical scheme; snakeskin-inspired surface

Address
Tae-Young Kim, Seong-Hun Jang and Song-Hun Chong: Department of Civil Engineering, Sunchon National University, 255 Jungang-ro,
Sunchon, Jeollanam-do 57922, Republic of Korea

Abstract
Bending fracture is a dominant failure pattern of soft-hard interbedded rock layers (SHIRLs). This study investigated the influence of bedding plane strength on the bending fracture behavior of SHIRLs using three-point-bending (TPB) tests and digital image correlation (DIC) technology. The test results indicate that the higher bedding plane strength reduces the dispersion of load-displacement curves, fracture displacement, fracture load and failure patterns. Specifically, in SHIRLs with strong bedding planes, the fracture load increases linearly with bedding plane strength, whereas the fracture displacement decreases linearly. In these cases, the instantaneous length of the main crack is approximately half of the sample. Conversely, in SHIRLs with weak bedding planes, the load-displacement curves, fracture displacement, fracture load and instantaneous crack length all exhibit significant dispersion. Particle flow code (PFC2D) is an effective numerical analysis method for exploring the bending fracture behavior of SHIRL under TPB test. Numerical simulation results further show that the bedding plane strength have significant impact on the fracture load, failure pattern and the proportion of tensile versus shear cracks. The findings of this study can provide theoretical reference and guidance for the reinforcement of SHIRLs.

Key Words
bending fracture; particle flow code; soft-hard interbedded rock layers; three-point-bending test

Address
Yang Liu and Hao Li: School of Architectural Engineering, Sichuan Polytechnic University, No. 801, SEC. 2,
Taishan South Road, Deyang, 618000, Sichuan, China
Da Huang: College of Geology Engineering and Geomatics, Chang'an University, 126 Yanta Road, Xi 'an, 710054, Shanxi, China

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2026 Techno-Press ALL RIGHTS RESERVED.
P.O. Box 33, Yuseong, Daejeon 34186 Korea.
General Inquiries: info@techno-press.com / Journal Administration: admin@techno-press.com