Geotechnical Engineering Commons^™

Identifying Payable Cluster Distributions For Improved Reservoir Characterization: A Robust Unsupervised Ml Strategy For Rock Typing Of Depositional Facies In Heterogeneous Rocks, Umar Ashraf, Aqsa Anees, Hucai Zhang, Muhammad Ali, Hung Vo Thanh, Yujie Yuan

Research outputs 2022 to 2026

The oil and gas industry relies on accurately predicting profitable clusters in subsurface formations for geophysical reservoir analysis. It is challenging to predict payable clusters in complicated geological settings like the Lower Indus Basin, Pakistan. In complex, high-dimensional heterogeneous geological settings, traditional statistical methods seldom provide correct results. Therefore, this paper introduces a robust unsupervised AI strategy designed to identify and classify profitable zones using self-organizing maps (SOM) and K-means clustering techniques. Results of SOM and K-means clustering provided the reservoir potentials of six depositional facies types (MBSD, DCSD, MBSMD, SSiCL, SMDFM, MBSh) based on cluster distributions. The depositional facies …

Stress-Dependent Mohr–Coulomb Shear Strength Parameters For Intact Rock, Hao Li, Leo Pel, Zhenjiang You, David Smeulders

Research outputs 2022 to 2026

Rock strength is imperative for the design and stability analysis of engineering structures. The Mohr–Coulomb (M-C) criterion holds significant prominence in geotechnical engineering. However, the M-C criterion fails to accurately capture the nonlinear strength response and neglects the critical state of rocks, potentially leading to inaccuracies in the design phase of deep engineering projects. This study introduces an innovative stress-dependent friction angle and cohesion (SFC) for the M-C criterion to capture the nonlinear strength responses of intact rocks, spanning from non-critical to critical states (brittle to ductile regions). A novel method for determining these stress-dependent parameters at each corresponding σ3 …

Evaluation Of 3d Beach Profiles: A New Method For Monitoring Changes In Beach Morphology And Grain Size, Kalinda Ellen Roberts

Graduate Masters Theses

Beach profiles are a simple and affordable approach to monitoring changes in beach morphology. However, traditional methods offer limited resolution and dimension. Recent advancements in technologies, particularly structure-from-motion (SfM) and grain size detection models (GSDMs), can be integrated into conventional beach profiling techniques, enabling more detailed spatial and temporal analysis of slope and grain sizes. This research introduces a new technique for coastal monitoring, termed “3D Beach Profiles,” which integrates SfM technology to create high-resolution three-dimensional digital surface models (DSMs) and orthomosaics of beach surfaces. These digital surfaces enable the extraction of beach slopes with orders of magnitude more data …

Formation Mechanism And Strengthening Method Of Geometric-Mechanical Structure Of Plugging Zone In Deep Naturally Fractured Reservoir, Chengyuan Xu, Honglin Zhang, Jianhong Fu, Yili Kang, Zhenjiang You

Research outputs 2022 to 2026

Efficient fracture plugging plays a critical role during drilling and completion of deep naturally fractured reservoirs, minimizing fluid loss, and ensuring reservoir protection. This study investigates the formation process of the geometric-mechanical structure of fracture plugging zones through a series of experiments including microscopic visualization, photoelastic and fracture plugging experiments. By examining these experiments, we reveal the relationship between lost circulation materials (LCMs) at the micro-scale, force chain network structures at the meso-scale, and the pressure stability of plugging zones at the macro-scale. Based on the analytic hierarchy process (AHP), we introduce an evaluation index for assessing the stability of …

Mutual Seismic Interaction Between Rigid Pile Inclusions And Surrounding Soft Soil Formation, Mohamed Mohamed Ahmed Abdelmotaal Eng., Ayman Lotfy Fayed Prof., Tamer Mohamed Sorour Associate Prof.

Journal of Engineering Research

This study aims to investigate the mutual interaction between rigid Pile Inclusions (PI) and the surrounding soft formations, such as soft to medium stiff silty Clay. The studied area is located at New Mansoura City, Nile Delta, Egypt, where the soil formation consists of a surface silty Sand layer with a depth of 4m, followed by 15m-thick Soft Clay formation. The third layer is medium dense to dense sand extending to a depth of 40, followed by a deep layer of very dense sand.

The Finite Element Method (FEM) is utilized to simulate this sophisticated seismic geotechnical problem, using PLAXIS-2D …

Numerical Study On Enhancing The Geotechnical Behavior Of Strip Footings On Oil-Contaminated Sand Using Stone Columns, Ahmad Nasr, Waseim Azzam, Mohamed Ahmed Mahmoud Abdelrehem

Journal of Engineering Research

Ground improvement techniques are frequently employed in construction sites characterized by weak soil conditions that may result in suboptimal performance. The use of ordinary and encased stone columns aims to enhance endurance, shear strength, and soil hardness, thereby mitigating settlement issues and expediting the consolidation of contaminated sand soils. In this research, a comprehensive investigation involving 74 cases was conducted to assess the behavior of both ordinary stone columns and encased stone columns under strip footing in contaminated sand subgrade. The objective was to discern the impact and characteristics of encapsulation in comparison to encapsulated stone columns, employing a Finite …

Incorporation Of Gnss Technology For Water-Level Instruments, Armaan S. Oberai, Toma Grundler, Serena B. Lee, Stefan A. Talke

College of Engineering Summer Undergraduate Research Program

Our goal was to take an existing water-level measuring embedded system and upgrade the GNSS module for the purpose of getting the elevation of the device within an error of 1 cm. Main milestones for the project included deploying a successful field test at a known survey point, using software-based post processing to improve the GNSS solution point, and implementing robust hardware and software for the water-level embedded system such that it was easily scalable.

Experimental Study Of Coal Fines Migration Characteristics In Reservoirs With Diverse Coal Structures: Influence On Reservoir Behavior, Yingchun Wei, Ziliang Liu, Xianyue Xiong, Tiancheng Xie, Biao Li, Anmin Wang, Daiyong Cao, Zhenjiang You

Research outputs 2022 to 2026

The challenge of coal fines production within tectonic coal reservoirs during coalbed methane (CBM) development in China presents a significant concern. In this study, coal samples with distinct coal structures from Hancheng mining area were selected for experiments on coal fines migration. Our analysis focused on the distinctive characteristics of coal fines generated by various coal structures, the subsequent alterations in sample permeability, and the changes in pore and fracture structures before and after the experiments. By examining the reservoir properties across different structures, we aimed to uncover the migration characteristics of coal fines in these diverse coal reservoirs and …

A Review Of Geopolymer Cement, From Two-Part Geopolymer To One-Part Geopolymer Cement And Its Geotechnical Applications, Khadhra Allali, Nabil Bella, Ilham Aguida Bella, Oussama Khodjet El Fehem, Maria Victoria Borrachero, Jordi Payá, José Monzó

Emirates Journal for Engineering Research

Abstract

Portland cement, a crucial construction material, has been used extensively in various geotechnical projects. However, its over-reliance has led to environmental concerns, particularly regarding carbon dioxide (CO₂) emissions during its production. Sustainable development involves the development of cement alternatives that are less damaging to the environment. Geopolymer cement can be a potential partial replacement for conventional Portland cement that can minimize carbon dioxide emissions and convert various by-products into useful products. Traditional geopolymer cement is composed of two components: an alkaline activator solution and a solid aluminosilicate precursor (other than water), and its production requires the manipulation …

Assessment Of Efficiencies Of Different Additives To Improve Cbr Value For The Highway Industry, Ahmed H. El-Bosraty Eng., Ahmed M. Ebid Dr., M. Bahr Prof.

Future Engineering Journal

The structural design of flexible or rigid paving layers depends on the strength of the foundation soil, which is expressed by the California Bearing Ratio (CBR). Soil strengthening and improvement techniques vary according to the type of soil, whether it is granular or cohesive. This study is concerned with evaluating the efficiency of three techniques used to improve the properties of granular soil, the first by using natural fibers, the second by using synthetic fibers, and the third by mixing with powders. The study methodology relies on reviewing, studying, classifying and comparing the previously published work in this context to …

Investigation Of Temperature, Solution Strength, And Applied Stress Effects On Cation Exchange Processes In Different Geosynthetic Clay Liner Products, Kendra Fuller

Master's Theses

An extensive laboratory test program was conducted to analyze and compare the cation exchange processes in three different varieties of sodium bentonite (Na-B) geosynthetic clay liners (GCLs) over increased conditioning durations up to 32 days and investigate the effects of temperature, solution strength, and applied stress. The goal of this test program was to establish whether the variables of temperature, solution strength, and applied stress improved or degraded the engineering properties of GCLs in laboratory testing and municipal solid waste (MSW) landfill applications. The GCLs were conditioned in liquids of increasing ionic strength, using deionized water and 2, 50, and …

Modeling Soil Lateral Deformation Due To Water Film Using Smoothed Particle Hydrodynamics, Erly Bahsan, Budi Susilo Soepandji, Wiwik Rahayu, R.R. Dwinanti R. Marthanty, Budianto Ontowirjo

Makara Journal of Technology

In geotechnical engineering, large deformation in soil materials is rarely simulated using numerical methods, particularly the finite element method and finite difference method, because they experience difficulties in representing the postfailure soil behavior. As an alternative to these methods, the smoothed particle hydrodynamics (SPH) method has recently been adopted to represent soil behavior. The SPH method is a Lagrangian, mesh-free numerical method in which the materials are modeled as a set of particles. In this method, soil behavior can be represented via the Drucker–Prager elasto–plastic failure criterion. Thus, this method can be used to simulate postfailure soil behavior and large …

Modeling The Influence Of Internal Factors On Vehicular Mobility Performance, Aziz Mdimi

Tanzania Journal of Engineering and Technology (TJET)

Traffic mobility is significantly influenced by road conditions and the internal factors governing vehicular performance. Internal factors play a crucial role in vehicular mobility, influencing vehicles operate and performance. While existing vehicular mobility models primarily address external factors, external factors such as governor, engine, gear train and differential unit remain underexplored. This study formulates a comprehensive model to address this gap, focusing on the internal components that affect vehicular mobility. The proposed model employs both analytical and numerical methods to derive transfer functions for these subsystems using Matrix Laboratory (MATLAB), aiming to capture the dynamic behavior of vehicles under various …

Balancing Results From Ai-Based Geostatistics Versus Fuzzy Inference By Game Theory Bargaining To Improve A Groundwater Monitoring Network, Masoumeh Hashemi, Richard C. Peralta, Matt Yost

Plants, Soils and Climate Student Research

An artificial intelligence-based geostatistical optimization algorithm was developed to upgrade a test Iranian aquifer's existing groundwater monitoring network. For that aquifer, a preliminary study revealed that a Multi-Layer Perceptron Artificial Neural Network (MLP-ANN) more accurately determined temporally average water table elevations than geostatistical kriging, spline, and inverse distance weighting. Because kriging is usually used in that area for water table estimation, the developed algorithm used MLP-ANN to guide kriging, and Genetic Algorithm (GA) to determine locations for new monitoring well location(s). For possible annual fiscal budgets allowing 1-12 new wells, 12 sets of optimal new well locations are reported. Each …

Time-To-Failure Prediction Of Fine-Grained Soil Slopes Subject To Weather-Driven Deterioration, Arm M. Morsy

Mineta Transportation Institute

Embankments have been widely used in the construction of transportation and flood defense infrastructure. Embankments constructed from clays experience a suite of weather-driven deterioration processes that lead to a progressive loss of hydromechanical performance, causing potentially severe and costly consequences. This study aimed to predict the time to failure of aging, deteriorating clay embankments supporting transportation infrastructure. A multi-phase numerical modeling approach was developed to replicate the long-term, weather-driven, hydromechanical behavior of clay embankments. This model simulated the behavior of a number of well-documented embankment failure case studies that had sufficient data to derive the necessary soil properties and climate …

In-Situ Micro-Ct Analysis Of Deformation Behavior In Sandwich-Structured Meta-Stable Beta Ti−35nb Alloy, Yu Jing Lui, Zi Lin Zhang, Jin Cheng Wang, Xiang Wu, Xiao Chun Liu, Wei Ying Huang, Lai Chang Zhang

Research outputs 2022 to 2026

Beta Ti−35Nb sandwich-structured composites with various reinforcing layers were designed and produced using additive manufacturing (AM) to achieve a balance between light weight and high strength. The impact of reinforcing layers on the compressive deformation behavior of porous composites was investigated through micro- computed tomography (Micro-CT) and finite element method (FEM) analyses. The results indicate that the addition of reinforcement layers to sandwich structures can significantly enhance the compressive yield strength and energy absorption capacity of porous metal structures; Micro-CT in-situ observation shows that the strain of the porous structure without the reinforcing layer is concentrated in the middle region, …

Base Case Shear-Wave Velocity Profiles And Non-Linear Material Property Models Of Local Site Conditions In South Carolina For Seismic Site Response Analyses, Ali Sedaghat Shirehjini

All Dissertations

This dissertation presents the development of base case small-strain shear-wave velocity ( ) profiles and non-linear materials property models of local site conditions in South Carolina for seismic site response analyses. The need to address South Carolina's seismic hazards is partly motivated by the 1886 Charleston earthquake (moment magnitude, M_w= 6.7 to 7.5). Required inputs for seismic site response analysis include profile down to a specified reference outcrop condition and non-linear material properties for each layer in the profile. Although firm rock (i.e., ≥ 2,500 ft/s) or hard rock (i.e., ≥ 9,850 ft/s) is commonly assumed for the …

Rock Structural Changes Monitored By Fibre Bragg Grating Sensors And Nuclear Magnetic Resonance During Static And Dynamic Carbonated Brine Core Flooding Experiments, Bruno Da Silva Falcão, Lionel Esteban, Ausama Giwelli, Ahmed Al-Yaseri, Alireza Keshavarz, Jeremie Dautriat, Stephanie Vialle, Stefan Iglauer

Research outputs 2022 to 2026

One proposed solution to reduce greenhouse gas emissions is the capture and storage of carbon dioxide (CCS) in geological formations such as depleted oil and gas reservoirs. Injected carbon dioxide (CO2) forms carbonic acid once dissolved in the formation water, which can lead to dissolution of certain types of rock minerals. This may weaken rock geomechanical properties that can jeopardize the safety of long-term storage. In this work, the use of Fibre Bragg Grating (FBG) sensors associated with Nuclear Magnetic Resonance (NMR) was investigated to measure the change in rock strain during core flooding experiments. Optical fibres were glued onto …

Advance On Rock-Breaking Cutter Steels: A Review Of Characteristics, Failure Modes, Molding Processes And Strengthening Technology, Ying Jiang, Bai Xin Dong, Jun Fan, Feng Qiu, Hong Yu Yang, Shi Li Shu, Fang Chang, Qi Chuan Jiang, Lai Chang Zhang

Research outputs 2022 to 2026

Rock breaking has always been a challenging problem that must be solved in projects such as excavating mountains, drilling wells, and constructing railways. Among the rock-breaking cutter steels, AISI H13 steel and wear-resistant high manganese steel have become the best choices. From the characteristics and failure modes of the two, rock-breaking cutter steels should simultaneously have high strength, high toughness and high wear resistance to avoid short-term fracture/damage and cost increase. Analyzing the problems existing in the molding process of rock-breaking cutter steels such as die casting, forging, and hot stamping, traditional strengthening technologies such as alloying optimization, heat treatment, …

Liquefaction Case Histories From Oceano, California During The 2003 San Simeon Earthquake, Hayden Brake

Master's Theses

On December 22nd, 2003, the Mw=6.5 San Simeon earthquake occurred 12 kilometers east of San Simeon, California, causing damage to buildings, roads, and other infrastructure throughout the central coast. The community of Oceano, 80 kilometers southeast of the epicenter, experienced damage to foundations, roads, and utilities due to liquefaction and lateral spreading. The unique geologic environment in Oceano caused a local amplification of ground motions, liquefaction, and lateral spreading. This study entailed developing ten liquefaction case histories from Oceano during the 2003 San Simeon earthquake. Four of the ten case histories are liquefaction cases and six are non-liquefaction cases, with …