Article
Acoustics
Arthur Bizzi, Eugenio L. Fortaleza, Tome S. N. Guenka
Summary: This study presents the first complete analytical solution to the mode-shape equation of the gravity-loaded Rayleigh-Timoshenko beam, providing closed-form descriptions of vibration modes for various structures under self-weight. The new solutions generalize multiple approximate and asymptotic solutions in existing literature, closely matching past numerical and experimental results as well as models built using the ANSYS software package.
JOURNAL OF SOUND AND VIBRATION
(2021)
Article
Engineering, Geological
Balaka Ghosh, Behzad Fatahi, Hadi Khabbaz, Huu Hung Nguyen, Richard Kelly
Summary: This study presents a numerical modelling of geosynthetic-reinforced composite ground supporting a road embankment, utilizing Modified Cam-Clay and Hoek-Brown constitutive models for soft soil and concrete columns respectively, validated with field monitoring data. The numerical results provide insights into load transfer mechanism and behavior of the composite ground system.
GEOTEXTILES AND GEOMEMBRANES
(2021)
Article
Acoustics
D. Colmenares, A. Andersson, R. Karoumi
Summary: This paper presents a closed-form solution to the moving harmonic load problem for continuous Euler-Bernoulli beam systems. By considering the generality of boundary conditions, natural frequencies and mode shapes are obtained through solving the characteristic equation. The main contribution of this paper is providing a closed-form solution for continuous footbridges with a moving harmonic load, which includes the phase angle in the load definition.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Engineering, Civil
Juan Camilo Molina-Villegas, Jorge Eliecer Ballesteros Ortega
Summary: The response of steel frame structures is affected by the rotational stiffness of the connections between beams and columns, which are characterized by nonlinear moment-rotation curves. Design codes require the inclusion of joint rotational stiffness in steel design models. This paper introduces the static formulation of the Green's Functions Stiffness Method for Timoshenko frames with zero-length elastic semi-rigid connections subjected to external loads. An example of a one-bay one-storey two-dimensional frame is presented.
Article
Mechanics
Alfio Francesco Siciliano, Leo Skec, Gordan Jelenic
Summary: An analytical model for a two-layer Timoshenko beam with interlayer slip, uplift, and rotational stiffness at the interface is presented in this study. The model provides closed-form solutions for the kinematic fields and corresponding tractions at the interface, considering linear-elastic behaviors. The results show that the rotational stiffness at the interface significantly affects the behavior of the composite beam, in addition to the tangential and normal stiffness. Furthermore, it is found that certain combinations of interface parameters can lead to opposite bending of unloaded layers, which has practical implications.
Article
Mechanics
Gongqi Cao, Yonggui Cheng, Zhangna Xue, Shiyang Liu, Jianlin Liu
Summary: This study comprehensively investigates the peeling behavior of a hard-magnetic soft sheet driven by the magnetic field, through both experimental and theoretical approaches. The effects of external magnetic field and work of adhesion on maximum deflection and adhered length are explored, and further results are predicted. These findings provide inspirations for engineering new devices such as smart structures, micro-sensors, and intelligent robots.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Geological
Azijul Islam, Sahadat Hossain, Faria Fahim Badhon, Prabesh Bhandari
Summary: The study demonstrated the effectiveness of using recycled-plastic pins (RPPs) in combination with a load transfer platform (LTP) for reducing ground settlement in soft foundation soil, applicable to various embankment and widening projects.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2021)
Article
Engineering, Civil
M. A. De Rosa, M. Lippiello
Summary: This paper proposes a novel analytical method for analyzing the dynamic behavior of a Timoshenko beam model on Winkler-type elastic soil, under simply-supported boundary conditions and with a crack. The approach is shown to be effective in studying vibration problems of Timoshenko beams by considering soil parameters, rotational and shear deformations, and crack presence. The results obtained are compared with existing literature, demonstrating very good outcomes.
ENGINEERING STRUCTURES
(2021)
Article
Mechanics
Reddy E. Ruocco, J. N. Reddy
Summary: In this study, a closed-form solution of the Reddy beam theory is developed and applied to investigate the bending behavior of straight and curved functionally graded beams. The obtained closed-form solution enriches the displacement field, strain, and stress quantities, which are particularly relevant in functionally graded beams. The adopted beam model satisfies the parabolic variation of shear stress and does not require shear correction factors, which is difficult to obtain in inhomogeneous beams.
COMPOSITE STRUCTURES
(2023)
Article
Engineering, Mechanical
Yong Xiao, Shuaixing Wang, Yongqiang Li, Jihong Wen
Summary: This work aims to develop efficient formulas for bandgap estimation and design of metastructures to control vibration and noise of mechanical structures. The closed-form formulas developed can accurately estimate bandgaps, design improved bandgaps, and their broad applicability is numerically verified in various beam-type metastructures with different scales.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Mathematics, Applied
M. V. B. Santana, P. B. Goncalves, R. A. M. Silveira
Summary: This work presents the development of analytical solutions for the symmetric free vibrations of pyramidal trusses, considering a general large strain measure and showcasing the influence of strain measure on results. Pyramidal trusses may have different analytical solutions in unloaded configurations depending on initial conditions: small amplitude vibrations or large cross-well vibrations.
PHYSICA D-NONLINEAR PHENOMENA
(2021)
Article
Engineering, Civil
Oscar A. Ardila-Giraldo, Santiago Pujol
Summary: Experimental evidence suggests that beams may undergo shear failure under blast load in the initial stages of response, limiting their energy absorption capacity. To prevent initial shear failure, it is important to quantify the likelihood of a change in failure mechanism from flexure to shear under blast load. Two simple numerical methods are proposed to estimate initial shear demand in beams subjected to blast, showing reasonable agreement with FEA results and experimental observations for preliminary blast-resistant design.
Article
Materials Science, Multidisciplinary
Zele Li, Mohammad Noori, Dipanjan Basu, E. Taciroglu, Zhishen Wu, Wael A. Altabey
Summary: This study investigates the dynamic response problem of the Timoshenko shear beam resting on a transversely isotropic viscoelastic foundation and subjected to a moving load. The results show that the developed shear model of the beam-soil system is accurate and effective.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART L-JOURNAL OF MATERIALS-DESIGN AND APPLICATIONS
(2022)
Article
Engineering, Geological
Shengmin Luo, Ning Lu
Summary: Soil water potential is defined as the sum of matric potential and osmotic potential, and the relationship between total soil water potential and water content is represented by the soil water isotherm. A closed-form soil water isotherm equation derived from a generalized soil water retention curve equation is experimentally validated for its accuracy in representing a wide range of soil types. The SWI equation is shown to outperform existing equations in representing soil-water interactions by adsorption and capillarity.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2021)
Article
Engineering, Geological
Changjie Zheng, Ming Chen, George Kouretzis
Summary: This paper presents a mathematical model for analyzing axially-loaded end-bearing piles in a two-layer elastic soil deposit. The model provides frictional stresses at the soil-pile interface and improves computational efficiency. The study reveals that the relative stiffness of the soil layers has a significant impact on the performance of the piles.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2023)
Article
Engineering, Geological
Habib Rasouli, Behzad Fatahi
Summary: This study investigates the effect of recycled carpet fibre on the mechanical response of clean sand under monotonic loading and cyclic loading, as well as the post-liquefaction resistance of soil. Results indicate that adding carpet fibre enhances the shear modulus and ductility of clean sand, improving both liquefaction and post-liquefaction resistances.
GEOTEXTILES AND GEOMEMBRANES
(2022)
Article
Engineering, Civil
Omar El-Hawat, Behzad Fatahi, Ertugrul Taciroglu
Summary: The rocking pile foundation system is a new design concept that aims to improve seismic performance of bridges by preventing plastic damage and reducing deck displacements. By integrating post-tensioned piles with rocking foundation, the proposed system shows superior performance compared to conventional fixed-base foundation systems.
EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS
(2022)
Article
Construction & Building Technology
Noor Sharari, Behzad Fatahi, Aslan S. Hokmabadi, Ruoshi Xu
Summary: This paper uses a three-dimensional numerical simulation technique to study the impact of foundation type on the seismic behavior of LNG tanks, and finds the importance of soil-foundation-structure interaction effects in evaluating the seismic response.
JOURNAL OF PERFORMANCE OF CONSTRUCTED FACILITIES
(2022)
Article
Construction & Building Technology
Amin Shafaghat, Hadi Khabbaz, Behzad Fatahi
Summary: This study presents a new mathematical equation for calculating the pile group efficiency in cohesionless soil under combined axial and lateral loading conditions, considering the tapering angle effect. The accuracy of the equation is validated through numerical and mathematical analyses.
JOURNAL OF PERFORMANCE OF CONSTRUCTED FACILITIES
(2022)
Article
Engineering, Geological
Noor Sharari, Behzad Fatahi, Aslan Hokmabadi, Ruoshi Xu
Summary: This study examines the seismic response of a 160,000 m(3) LNG tank supported by reinforced concrete piles on a liquefiable soil. The results show that liquefaction of the soil increases stress concentrations and risks in the tank, as well as affects the lateral displacements, shear forces, and bending moments in the piles.
BULLETIN OF EARTHQUAKE ENGINEERING
(2022)
Article
Engineering, Industrial
Mehrnaz Alibeikloo, Hadi Khabbaz, Behzad Fatahi
Summary: This paper analyzes the time-dependent behavior of soft soils and incorporates the spatial variability of soil characteristics. By using generated random fields for analysis, the impact of spatial variability on long-term settlement predictions is evaluated, confirming the importance of considering spatial correlation length for design reliability.
RELIABILITY ENGINEERING & SYSTEM SAFETY
(2022)
Article
Engineering, Civil
Hayder A. Hasa, Sabah H. Lafta, Muhannd W. Majeed, Hadi Khabbaz, Mehdi Aghayarzadeh
Summary: Providing a stable foundation system is crucial for reducing the geotechnical risk in construction projects. Pile foundations are recommended for increasing bearing capacity and reducing dynamic soil oscillations. This study reviewed the use of microbially induced calcite precipitation (MICP) for soil stabilization and evaluated its effectiveness on a single pervious concrete pile under static, free vibration, and earthquake conditions using Plaxis 3D. The results showed that MICP treatment significantly increased the static load capacity of loose sand and demonstrated insignificant effects on vertical and lateral displacement during earthquakes.
INTERNATIONAL JOURNAL OF GEOMATE
(2022)
Article
Engineering, Geological
Zhengheng Xu, Hadi Khabbaz, Behzad Fatahi, Di Wu
Summary: This paper develops a novel numerical model and utilizes machine learning methods to achieve real-time estimation of soil stiffness during compaction. The results can help engineers interpret roller drum acceleration data and estimate the level of compaction and ground stiffness.
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2022)
Article
Biotechnology & Applied Microbiology
Namuun Ganbat, Ali Altaee, John L. Zhou, Thomas Lockwood, Raed A. Al-Juboori, Faris M. Hamdi, Elika Karbassiyazdi, Akshaya K. Samal, Alaa Hawari, Hadi Khabbaz
Summary: This study assessed the use of electrokinetic technology as an in-situ remediation method for removing PFOA from soil. The surfactant-enhanced electrokinetic technique showed promising results in effectively removing PFOA, especially when NaC was added.
ENVIRONMENTAL TECHNOLOGY & INNOVATION
(2022)
Article
Engineering, Civil
Zhengheng Xu, Hadi Khabbaz, Behzad Fatahi, Di Wu
Summary: Intelligent Compaction (IC) technology has gained increasing attention in real-time quality control of compacted soil layers due to its high efficiency and full-area coverage. However, accurate real-time determination of the soil modulus during compaction based on roller acceleration has been challenging. This study adopts a double-layered soil profile and a three-dimensional finite element model to predict the double-layered soil modulus using an advanced machine learning approach, showing potential for real-time quality control by site engineers.
ENGINEERING STRUCTURES
(2023)
Article
Engineering, Geological
Richard C. Stone Jr, Visar Farhangi, Behzad Fatahi, Moses Karakouzian
Summary: This study introduces a new composite foundation system called caliche stiffened pile (CSP), which utilizes competent caliche layers bonded to the top and bottom of a continuous flight auger (CFA) pile to optimize the required pile length. Settlements of a high-rise building with CSP foundation were monitored and full-scale tests were conducted to measure piles' capacity. Finite element back analyses were performed to determine soil stiffness parameters and investigate the impacts of CSP on controlling pile foundation settlement and optimizing pile length.
CANADIAN GEOTECHNICAL JOURNAL
(2023)
Article
Engineering, Geological
Waranga Habaraduwa Peellage, Behzad Fatahi, Haleh Rasekh
Summary: This study investigated the cyclic shear stress characteristics of jointed rock specimens through cyclic triaxial tests. The results indicate that there exists a critical dynamic deviatoric stress beyond which the jointed rock specimens yield. Minor cumulative residual strains and hysteresis damping were observed below the critical dynamic deviatoric stress, while plastic strains increased and resilient moduli degraded rapidly beyond this critical stress level.
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2023)
Article
Engineering, Geological
Thang Le, Sachit Desa, Hadi Khabbaz
Summary: Sugarcane is the second largest export crop in Australia. Industrial production of sugar results in a by-product called bagasse fly ash (BFA). This study explores the potential of BFA as a pozzolan for stabilizing expansive soils. The findings indicate that BFA with a larger particle size yields higher compressive strength and lower shrinkage. BFA can potentially replace concrete in road work projects and other applications involving expansive soils.
AUSTRALIAN GEOMECHANICS JOURNAL
(2023)
Article
Construction & Building Technology
Esmaeil Lal Mohammadi, Elmira Khaksar Najafi, Payam Zanganeh Ranjbar, Meghdad Payan, Reza Jamshidi Chenari, Behzad Fatahi
Summary: This study evaluates the usability of a recycled alkaline solution to enhance the strength and stiffness of clayey soil. Experiments were conducted to determine the proper type and content of precursors and the efficiency of binary solutions. The results showed that the residual alkaline solution activated high-calcium fly ash better than low-calcium fly ash. Microstructural analysis revealed the formation of dense structures, leading to significant improvement in the maximum strength and stiffness of the treated soil. The environmentally friendly binary solutions performed better in terms of CO2 emissions and strength gain compared to conventional materials.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
