Geotechnics最新文献_第2页

Influence of Settlement on Base Resistance of Long Piles in Soft Soil—Field and Machine Learning Assessments 沉降对软土中长桩基抗力的影响--现场和机器学习评估

Geotechnics Pub Date : 2024-05-03 DOI: 10.3390/geotechnics4020025

Thanh T. Nguyen, Viet D. Le, T. Q. Huynh, Nhu H. T. Nguyen

{"title":"Influence of Settlement on Base Resistance of Long Piles in Soft Soil—Field and Machine Learning Assessments","authors":"Thanh T. Nguyen, Viet D. Le, T. Q. Huynh, Nhu H. T. Nguyen","doi":"10.3390/geotechnics4020025","DOIUrl":"https://doi.org/10.3390/geotechnics4020025","url":null,"abstract":"Understanding the role that settlement can have on the base resistance of piles is a crucial matter in the design and safety control of deep foundations under various buildings and infrastructure, especially for long to super-long piles (60–90 m length) in soft soil. This paper presents a novel assessment of this issue by applying explainable machine learning (ML) techniques to a robust database (1131 datapoints) of fully instrumented pile tests across 37 real-life projects in the Mekong Delta. The analysis of data based on conventional methods shows distinct responses of long piles to rising settlement, as compared to short piles. The base resistance can rapidly develop at a small settlement threshold (0.015–0.03% of pile’s length) and contribute up to 50–55% of the total bearing capacity in short piles, but it slowly rises over a wide range of settlement to only 20–25% in long piles due to considerable loss of settlement impact over the depth. Furthermore, by leveraging the advantages of ML methods, the results significantly enhance our understanding of the settlement–base resistance relationship through explainable computations. The ML-based prediction method is compared with popular practice codes for pile foundations, further attesting to the high accuracy and reliability of the newly established model.","PeriodicalId":505610,"journal":{"name":"Geotechnics","volume":"19 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141015548","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

Improving Strength by Increased Compaction of Gypsum—Enriched Soil under Long-Term Soaking Conditions 在长期浸泡条件下通过增加石膏富集土的压实度来提高强度

Geotechnics Pub Date : 2024-04-23 DOI: 10.3390/geotechnics4020023

S. Razouki, D. Kuttah

{"title":"Improving Strength by Increased Compaction of Gypsum—Enriched Soil under Long-Term Soaking Conditions","authors":"S. Razouki, D. Kuttah","doi":"10.3390/geotechnics4020023","DOIUrl":"https://doi.org/10.3390/geotechnics4020023","url":null,"abstract":"This study investigated the effect of compaction effort and soaking time on the shear strength properties of fine-grained gypsum-containing soils. The objective was to demonstrate that increasing compaction effort increases soil strength, specifically cohesion and the angle of shear strength, when subjected to soaking in freshwater. Unconsolidated undrained triaxial tests were carried out on CBR soil samples with different soaking times. The results showed a transition from brittle to ductile failure behaviour as the soaking time increased. Mohr–Coulomb failure envelopes showed reduced cohesion and angle of shear strength with increasing soak time. Regression models were developed to establish correlations between soaked and unsoaked strength parameters. Strong relationships were found between soil strength properties, compaction effort and soaking time. Empirical equations were proposed to estimate the cohesion and angle of shear strength from compaction effort and soaking time. This study highlighted the importance of considering gypsum-rich soils in civil engineering design. Gypsum dissolution during wetting significantly affected soil strength parameters. The regression models and empirical equations provide engineers with tools to assess the influence of compaction effort and soaking time on soil strength, thus aiding decision making when designing structures on gypsum-rich soils.","PeriodicalId":505610,"journal":{"name":"Geotechnics","volume":"65 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140670851","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

Application of Electrical Resistivity Tomography in Geotechnical and Geoenvironmental Engineering Aspect 电阻率层析成像技术在岩土工程和地质环境工程中的应用

Geotechnics Pub Date : 2024-04-04 DOI: 10.3390/geotechnics4020022

Md Jobair Bin Alam, Asif Ahmed, Md Zahangir Alam

{"title":"Application of Electrical Resistivity Tomography in Geotechnical and Geoenvironmental Engineering Aspect","authors":"Md Jobair Bin Alam, Asif Ahmed, Md Zahangir Alam","doi":"10.3390/geotechnics4020022","DOIUrl":"https://doi.org/10.3390/geotechnics4020022","url":null,"abstract":"Electrical resistivity tomography (ERT) has turned out to be one of the most applied and user-friendly geophysical methods in geotechnical and geoenvironmental research. ERT is an emerging technology that is becoming popular nowadays for investigating subsurface conditions. Multiple attributes of the technology using various electrode configurations significantly reduce measurement time and are suitable for applications even in hardly accessible mountain areas. It is a noninvasive test for subsurface characterization and a very sensitive method used to determine geophysical properties, i.e., structural integrity, water content, fluid composition, etc. This paper aimed to elucidate the ERT technique’s main features and applications in geotechnical and geoenvironmental engineering through four case studies. The first case study investigated the possible flow paths and areas of moisture accumulation after leachate recirculation in a bioreactor landfill. The second case study attempted to determine the moisture variation along highway pavement. The third case study explored the slope failure investigation by ERT. The fourth case study demonstrated the efficiency of the ERT method in the landfill evapotranspiration (ET) cover to investigate moisture variation on a broader scale and performance monitoring. In all of the four cases, ERT exhibited promising performance.","PeriodicalId":505610,"journal":{"name":"Geotechnics","volume":"12 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140741233","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

Assessment of Bayesian Changepoint Detection Methods for Soil Layering Identification Using Cone Penetration Test Data 评估利用锥入度测试数据识别土壤分层的贝叶斯变化点检测方法

Geotechnics Pub Date : 2024-04-04 DOI: 10.3390/geotechnics4020021

S. Suryasentana, Brian B. Sheil, M. Lawler

引用次数: 0

Improved Wave Equation Analysis for Piles in Soil-Based Intermediate Geomaterials with LRFD Recommendations and Economic Impact Assessment 基于 LRFD 建议和经济影响评估的土基中间土工材料中桩的改进波浪方程分析

Geotechnics Pub Date : 2024-04-01 DOI: 10.3390/geotechnics4020020

Harish K. Kalauni, N. B. Masud, Kam Ng, S. Wulff

{"title":"Improved Wave Equation Analysis for Piles in Soil-Based Intermediate Geomaterials with LRFD Recommendations and Economic Impact Assessment","authors":"Harish K. Kalauni, N. B. Masud, Kam Ng, S. Wulff","doi":"10.3390/geotechnics4020020","DOIUrl":"https://doi.org/10.3390/geotechnics4020020","url":null,"abstract":"The Wave Equation Analysis of Pile Driving (WEAP) has been widely used to determine drivability, predict static resistance, and assure the integrity of piles in soils. Assigning static and dynamic properties of Soil-based Intermediate Geomaterials (S-IGMs) remains a challenge in WEAP, partly attributed to IGMs that act as transition geomaterials between soil and hard rock. Furthermore, reliable static analysis methods for unit resistance predictions are rarely available for driven piles in S-IGMs in the default WEAP method. To alleviate these challenges, this study presents improved WEAP methods for steel piles driven in S-IGMs, including proposed damping parameters and Load and Resistance Factor Design (LRFD) recommendations based on newly developed static analysis methods and the classification of S-IGMs. A back calculation approach is used to generate the appropriate damping parameters for S-IGMs for three distinct subsurface conditions utilizing a database of 34 steel H- and pipe piles. Newly developed WEAP and LRFD procedures are also recommended. Additional independent 22 test pile data are used to compare and evaluate the accuracy and efficiency of the proposed WEAP methods with the default WEAP method. Compared with the default WEAP, bearing graph analysis results revealed that the selected proposed WEAP method, on average, reduces the underprediction of pile resistances by 6% and improves the reliability with a 43% reduction in the coefficient of variation (COV). Calibrated resistance factors for the proposed WEAP method increase to as high as 0.75 compared to the current AASHTO recommendation of 0.50. An economic impact assessment reveals that the proposed WEAP method is more efficient than the default WEAP method as the average difference in steel weight for 32 test piles is 0.06 kg/kN, almost close to zero, reducing the construction challenges in the current engineering practice.","PeriodicalId":505610,"journal":{"name":"Geotechnics","volume":"9 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140786340","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

An Anchoring Capacity Study Focused on a Wheel’s Curvature Geometry for an Autonomous Underwater Vehicle with a Traveling Function during Contact with Loose Ground Containing Water 以具有行驶功能的自主式水下航行器在与含水松软地面接触时的车轮曲率几何为重点的锚定能力研究

Geotechnics Pub Date : 2024-03-25 DOI: 10.3390/geotechnics4020019

Akira Ofuchi, Daisuke Fujiwara, Kojiro Iizuka

{"title":"An Anchoring Capacity Study Focused on a Wheel’s Curvature Geometry for an Autonomous Underwater Vehicle with a Traveling Function during Contact with Loose Ground Containing Water","authors":"Akira Ofuchi, Daisuke Fujiwara, Kojiro Iizuka","doi":"10.3390/geotechnics4020019","DOIUrl":"https://doi.org/10.3390/geotechnics4020019","url":null,"abstract":"The current scallop fishery sector allows many scallops to remain in specified fishing zones, and this process leads to heavy losses in the sector. Scallop fishermen aim to harvest the remaining scallops to reduce their losses. To achieve this, a fisherman must understand the scallop ecology on the seafloor. In our previous study, we proposed a method for measuring scallops using wheeled robots. However, a wheeled robot must be able to resist disturbance from the sea to achieve high measurement accuracy. Strong anchoring of wheels against the seafloor is necessary to resist disturbance. To better understand anchoring performance, we confirmed the wheel anchoring capacity in water-containing sand in an experiment. In this experiment, we towed fixed wheels on water-containing sand and measured the resistance force acting between the wheel and the sand. Afterward, we considered the resistance force as the wheel anchoring capacity on the water-containing sand. The experimental results capture the tendency for the anchoring capacity of sand with/without water to increase with sinkage. The results also demonstrate that the anchoring capacity of water-containing sand is lower than that of non-water-containing sand. However, the results indicate that when the wheels possess lugs, their presence tends to increase the wheels’ anchoring capacity in water.","PeriodicalId":505610,"journal":{"name":"Geotechnics","volume":" 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140381808","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

Impact of Gap-Graded Soil Geometrical Characteristics on Soil Response to Suffusion 沟壑纵横的土壤几何特征对土壤吸水反应的影响

Geotechnics Pub Date : 2024-03-21 DOI: 10.3390/geotechnics4010018

Chen Dong, Mahdi Disfani

引用次数: 0

Flow through and Volume Change Behavior of a Compacted Expansive Soil Amended with Natural Biopolymers 用天然生物聚合物改良的压实膨胀土的流动和体积变化行为

Geotechnics Pub Date : 2024-03-20 DOI: 10.3390/geotechnics4010017

Ahmed Bukhary, S. Azam

{"title":"Flow through and Volume Change Behavior of a Compacted Expansive Soil Amended with Natural Biopolymers","authors":"Ahmed Bukhary, S. Azam","doi":"10.3390/geotechnics4010017","DOIUrl":"https://doi.org/10.3390/geotechnics4010017","url":null,"abstract":"Natural biopolymers offer a sustainable alternative for improving soil behavior due to their inert nature, small dosage requirement, and applicability under ambient temperatures. This research evaluates the efficacy of natural biopolymers for ameliorating an expansive soil by using a 0.5% dosage of cationic chitosan, charge-neutral guar gum, and anionic xanthan gum during compaction. The results of laboratory investigations indicate that the flow through and volume change properties of the expansive soil were affected variably. The dual porosity, characterized by low air entry due to inter-aggregate pores (AEV1 of 4 kPa) and high air entry due to the clay matrix (AEV2 of 200 kPa) of the soil, was healed using chitosan and guar gum (AEV of 200 kPa) but was enhanced by the xanthan gum (AEV1 of 100 kPa and AEV2 of 200 kPa). The s-shaped swell–shrink path of the soil comprised structural (e from 1.23 to 1.11), normal (e from 1.11 to 0.6), and residual stages (e ranged from 0.6–0.43). This shape was converted into a j-shaped path through amendment using chitosan and guar gum, showing no structural volume change, with e from about 1.25 to 0.5, but was reverted to a more pronounced form by xanthan gum, with e from 1.5 to 1.32, 1.32 to 0.49, and 0.49 to 0.34 in the three stages, respectively. The consolidation behavior of the soil was largely unaffected by the addition of biopolymers such that the saturated hydraulic conductivity decreased from 10−9 m/s to 10−12 m/s over a void ratio decrease from 1.1 to 0.6. At a seating stress of 5 kPa, the swelling potential (7.8%) of the soil slightly decreased to 6.9% due to the addition of chitosan but increased to 9.4% and 12.2% with guar gum and xanthan gum, respectively. The use of chitosan and guar gum will allow the compaction of the investigated expansive soil on the dry side of optimum.","PeriodicalId":505610,"journal":{"name":"Geotechnics","volume":"27 43","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140226878","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

Dissipated Energy and Pore Pressure Generation Patterns in Sands and Non-Plastic Silts Subjected to Cyclic Loadings 受循环荷载作用的砂和非弹性淤泥中的耗散能量和孔隙压力产生模式

Geotechnics Pub Date : 2024-02-29 DOI: 10.3390/geotechnics4010014

C. Polito, James R. Martin

引用次数: 0

Stabilization of Shallow Landslides Induced by Rainwater Infiltration—A Case Study from Northern Croatia 雨水渗透诱发浅层滑坡的稳定--克罗地亚北部的案例研究

Geotechnics Pub Date : 2024-02-28 DOI: 10.3390/geotechnics4010013

Jasmin Jug, Kristijan Grabar, A. bek, Stjepan Strelec

{"title":"Stabilization of Shallow Landslides Induced by Rainwater Infiltration—A Case Study from Northern Croatia","authors":"Jasmin Jug, Kristijan Grabar, A. bek, Stjepan Strelec","doi":"10.3390/geotechnics4010013","DOIUrl":"https://doi.org/10.3390/geotechnics4010013","url":null,"abstract":"Climate change brings with it phenomena such as large amounts of rainfall in short periods. Infiltration of rainwater into clayey soils is a common trigger for shallow landslides on slopes. In this way, numerous shallow landslides occur in the area of northern Croatia, and a characteristic example is the landslide “Orehovčak”. To stop the sliding of the destabilized slope, it was necessary to solve the drainage of water that infiltrates the landslide body. For this purpose, detailed geotechnical investigations and monitoring were conducted. Many data were collected at the investigation site, especially soil characteristics and groundwater fluctuations. The surface soil on the slope consists of highly plastic clay, and the sliding surface was created in contact with the solid subsoil of marl, the depth of which varies positionally. The analyses confirmed that water is a slip trigger. To solve the problem, excavations and installation of deep drains were performed. The slope safety factor confirms landslide stabilization, whose calculated value after rehabilitation was Fs = 1.645. Inclinometer readings carried out after remediation show that slope slippage stopped. This confirms that the presented remediation method is very applicable to shallow landslides in northern Croatia and similar landslides around the world.","PeriodicalId":505610,"journal":{"name":"Geotechnics","volume":"129 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140417838","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