Article
Engineering, Civil
Yuxing Yang, Amit H. Varma, Michael E. Kreger, Ying Wang, Kai Zhang
Summary: The study proposed the use of T-headed bars as shear reinforcement in concrete structures to alleviate rebar congestion and installation difficulties caused by conventional single-leg stirrups. Tests showed that specimens with T headed bars exhibited higher shear strength compared to those with stirrups, while exhibiting similar behavior. Design codes from six countries were found to provide conservative estimates of shear strength for specimens with T-headed bars.
ENGINEERING STRUCTURES
(2021)
Review
Computer Science, Interdisciplinary Applications
Gabriel Hattori, Mark Hobbs, John Orr
Summary: Concrete, the most widely used man-made material globally, plays a crucial role in rapidly urbanizing built environments, but its failure behavior in shear remains poorly understood. Peridynamics offers potential for a general concrete model, but its focus on applications with reinforcement is lacking. The lack of robust model validation assessing strengths and weaknesses is also a barrier to a general model.
ARCHIVES OF COMPUTATIONAL METHODS IN ENGINEERING
(2021)
Article
Construction & Building Technology
Asmaa Said, Mahmoud Elsayed, Ahmed Abd El-Azim, Fadi Althoey, Bassam A. Tayeh
Summary: This paper evaluates the effectiveness of using ultra-high performance fiber reinforced concrete (UHPFRC) as a strengthening technique to improve the shear strength of RC beams. The experimental results show that UHPFRC is an effective technique, significantly improving the ultimate shear strength, initial stiffness, ductility, and toughness of the beams. Full casting of UHPFRC and strengthening with vertical or inclined strips were found to have a substantial contribution in increasing shear capacity.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Mechanics
Liang Xue, Xiaodan Ren, Roberto Ballarini
Summary: This paper proposes a new stress decomposition procedure, called shear-normal decomposition, to establish a damage-plasticity constitutive relationship for concrete specifically considering shear failure. The model accounts for the degradation of concrete's mechanical performance through shear, tension, and compression damage variables. It also presents calibration experiments to determine the shear stress-shear strain curve and considers the coupling between tension-shear and compression-shear using a shear damage evolution criterion.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Construction & Building Technology
Haifeng Yang, Xiancheng Lu, Machi Gong, Peng Yang
Summary: Rubber powder produced from waste tires can improve the impact and shear toughness of concrete, as well as reduce environmental pollution. However, there is a lack of research on the mechanical behaviors and failure criteria of steel fiber reinforced rubber concrete (SFRRC) under combined compression-shear loading. This study investigated the effects of steel fiber and rubber powder content, and compressive stress ratio on the compression-shear properties of SFRRC. The results showed that SFRRC exhibited ductile failure under higher compressive stress ratios and the addition of steel fiber increased shear strength and peak displacement.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Engineering, Civil
Yu-Chen Ou, Jhe-Yan Li, Hwasung Roh
Summary: The study found that reinforced concrete columns with five-spiral reinforcement have slightly lower shear strength compared to traditional tied columns, but exhibit greater durability in shear performance. Failure of the five-spiral columns is mainly attributed to spiral fracture, while traditional tied columns fail due to hook anchorage failure. Furthermore, the modified DCSS model can provide a conservative estimation of the shear strength contributed by five-spiral reinforcement.
ENGINEERING STRUCTURES
(2021)
Article
Construction & Building Technology
A. Deifalla
Summary: This study aims to develop a mechanical model based on the physical punching shear behavior of FRP-reinforced concrete slabs. An extensive experimental database was collected with 189 FRP-reinforced concrete slabs from 37 different studies. A new mechanical model was developed and proposed based on the critical shear crack theory (CSCT) to accurately predict the strength and rotation of FRP-reinforced concrete slabs under punching shear.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Engineering, Civil
Bichitra Singh Negi, Kranti Jain
Summary: A mechanics-based mathematical model is proposed to predict the shear strength of steel fiber reinforced concrete beams and quantify the contribution of each shear resisting mechanism.
Article
Engineering, Civil
M. S. Sandeep, Koravith Tiprak, Sakdirat Kaewunruen, Phoonsak Pheinsusom, Withit Pansuk
Summary: In recent years, machine learning techniques have been widely applied in solving challenging structural engineering problems, providing highly accurate models to replace empirical and semiempirical prediction models. This paper discusses the fundamental terminologies and concepts of commonly used machine learning algorithms for solving structural engineering problems. It also presents a comprehensive literature review on the application of machine learning in predicting shear strength, covering various types of beams. The article concludes with major observations, challenges, and future scope in this field. It serves as a valuable resource for individuals unfamiliar with machine learning but eager to learn more.
Article
Construction & Building Technology
Thushara Jayasinghe, Tharaka Gunawardena, Priyan Mendis
Summary: This study investigates the parameters affecting the reserve strength of shear reinforcement using shear test data, and evaluates minimum shear reinforcement provisions in Australian concrete code, bridge design code, and American concrete institute code. The results reveal discrepancies in safety margins among the standards, with the proposed 0.75 factor showing greater efficiency in increasing safety margins compared to the k(s) factor.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Min Sook Kim, Young Hak Lee
Summary: The experimental evaluation showed that increasing the amount of GFRP shear reinforcement and reducing spacing can improve the shear strength of reinforced concrete flat plates. This type of shear reinforcement also alters the crack pattern and failure mode of specimens. Additionally, existing equations provided by design codes underestimate the shear strength for concrete flat plates shear reinforced with GFRP vertical grids, with the BS 8110 equation offering more accurate results.
APPLIED SCIENCES-BASEL
(2021)
Review
Construction & Building Technology
Ruslan Ibragimov, Evgenij Korolev, Timur Deberdeev, Igor Dolbin
Summary: This article studies the impact of electromagnetic fields on the degradation of reinforced concrete structures, identifying two main types of radiation: ionizing and non-ionizing. Under the influence of ionizing radiation, significant changes occur in the structure of reinforced concrete, leading to a loss of strength. Prolonged exposure to non-ionizing radiation also causes corrosion in reinforced concrete structures.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Baek-Il Bae, Moon-Sung Lee, Chang-Sik Choi, Hyung-Suk Jung, Hyun-Ki Choi
Summary: Fiber volume fraction is the most influential factor on the ultimate strength of UHPFRC flexural members, with 2% steel fiber inclusion significantly enhancing both flexural and shear strength, and altering the failure mode. The ultimate flexural strength is affected by the size and shape of the stress block.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Civil
Oumaima Abra, Mahdi Ben Ftima
Summary: This work presents an enhanced computational design method for complex reinforced concrete structures. The method extends the applicability of a previously developed method to 3D stress states and various tension stiffening and incompatibility laws. It addresses the limitations of existing methods and provides important results regarding nodal zone shape, incompatibility, and strut development conditions.
ENGINEERING STRUCTURES
(2022)
Article
Construction & Building Technology
Wisena Perceka, Wen-Cheng Liao
Summary: This study proposes shear strength prediction equations for steel fiber-reinforced concrete (SFRC) columns based on observations from test results. The proposed equations demonstrate higher accuracy in predicting shear strength compared to other equations.
ACI STRUCTURAL JOURNAL
(2023)
Article
Engineering, Civil
Tarun K. Singhal, Oh-Sung Kwon, Evan C. Bentz, Constantin Christopoulos
Summary: This study proposes a Civil Infrastructure Resilience Assessment Framework to evaluate seismic fragility and resilience, quantifying functionality loss, recovery time, repair cost, and overall resilience using a Bayesian Network approach. An engineering tool is developed to simplify stakeholders' decision-making process.
STRUCTURE AND INFRASTRUCTURE ENGINEERING
(2022)
Article
Construction & Building Technology
Jacob Yager, Neil A. Hoult, Evan Bentz
Summary: Functionally graded concrete (FGC) has the potential to lower cement content and reduce CO2 emissions, but its behavior is not fully understood. Testing horizontally and vertically layered FGC (HLFGC, VLFGC) revealed that using fiber reinforced concrete can increase load carrying capacity and reduce cracking in FGC beams, while cracking at interfaces can lead to lower cracking strengths.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Jack J. Poldon, Evan C. Bentz, Neil A. Hoult
Summary: This study examined the use of distributed measurements from a large reinforced concrete beam test to investigate the impact of various factors on longitudinal reinforcement. It was found that the demand on the longitudinal reinforcement due to shear increased, and the average angle of principal compressive stress decreased with applied load.
STRUCTURAL CONCRETE
(2022)
Article
Engineering, Civil
Jack Gillham, Evan C. Bentz, Neil A. Hoult
Summary: This study utilizes distributed fiber optic sensors (DFOS) measurements to derive support reactions and detect local damage on flexural members of a bridge. Through a series of load tests, it is demonstrated that DFOS measurements play a crucial role in assessing bridge performance and adjustments for geometry variations can be made through calibration.
ENGINEERING STRUCTURES
(2022)
Article
Construction & Building Technology
Edvard P. G. Bruun, Evan C. Bentz
Summary: This paper introduces a mechanics-based finite element for analyzing shear-critical slender reinforced concrete beams and columns, which can accurately capture load-deformation behavior and simplify modeling complexity and user decisions.
JOURNAL OF STRUCTURAL ENGINEERING
(2022)
Article
Engineering, Civil
Jack Gillham, Neil A. Hoult, Evan C. Bentz
Summary: Measuring reaction forces at bridge bearings is crucial for detecting damage and maintaining bridges. Distributed fiber optic sensors (DFOS) can be used to measure curvature in bridge beams and calculate the moment, shear, and reaction force due to live loading. The study highlights the importance of selecting a DFOS system with appropriate accuracy and precision.
JOURNAL OF BRIDGE ENGINEERING
(2022)
Article
Chemistry, Analytical
Jacob S. Yager, Neil A. Hoult, Evan C. Bentz, Joshua E. Woods
Summary: Shrinkage is a complex time-dependent phenomenon in reinforced concrete structures, influenced by various factors. Distributed fibre optic sensing provides a method to measure both restrained and unrestrained shrinkage in small-scale specimens and structural elements. The study developed and evaluated methods to measure distributed unrestrained shrinkage strains and studied restrained shrinkage strains in different types of structural members. The findings showed high variability in unrestrained shrinkage strains depending on location and non-uniform shrinkage strain distributions in restrained shrinkage strains due to functional grading and high supplementary cementitious material concretes.
Article
Construction & Building Technology
Jack Gillham, Richard Sturm, Neil A. Hoult, Evan C. Bentz
Summary: This paper explores the potential of using distributed fiber optic sensing (DFOS) to assess load distribution and support reactions in statically indeterminate structures. A multibeam two-span composite model bridge was built and equipped with DFOS instrumentation. Different loading scenarios and slab thicknesses were used to examine their effects on load distribution and reaction forces. The challenge of measuring shear forces and reactions near the supports was overcome by developing and evaluating extrapolation techniques. The study demonstrates the accuracy and applicability of DFOS technology for estimating reactions in real-life structures.
JOURNAL OF STRUCTURAL ENGINEERING
(2023)
Article
Construction & Building Technology
Julia A. Bruce, Evan C. Bentz, Oh-Sung Kwon
Summary: This paper summarizes the results of a pilot experimental program intended to develop a robust data for global airflow through cracked concrete, with comparisons against a traditionally used prediction method.
ACI MATERIALS JOURNAL
(2022)
Article
Construction & Building Technology
Allan Kuan, Evan C. Bentz, Michael P. Collins
Summary: This paper presents a rational model for predicting the strength of heavily reinforced concrete members that fail by crushing, which is more accurate than design codes such as ACI 318-19 and CSA A23.3:19. The model takes into account the variation in torsional stresses through the thickness of a member using stress block factors derived from the stress-strain curve of the concrete. The predictions of the model have a higher accuracy compared to the maximum torsion limits in existing design codes, with an average test-to-predicted ratio of 1.20 and a coefficient of variation of 14.4%.
ACI STRUCTURAL JOURNAL
(2022)
Article
Construction & Building Technology
Jacob Yager, Neil A. Hoult, Evan C. Bentz, Joshua Woods
Summary: Novel functionally graded concrete deep beams without transverse reinforcement were constructed for transfer girder applications. The beams were tested and monitored, revealing the highest load capacity increase in diagonal-shaped embedded struts. Distributed fiber-optic sensors (DFOS) enhanced the understanding of the strut-and-tie mechanisms.
ACI STRUCTURAL JOURNAL
(2022)
Article
Construction & Building Technology
Jack J. Poldon, Neil A. Hoult, Evan C. Bentz
Summary: This study used distributed fiber-optic sensors and digital image correlation to investigate the shear-carrying mechanism in reinforced concrete beams. The results have provided insights into the main elements of shear resistance for the first time.
ACI STRUCTURAL JOURNAL
(2022)
Article
Construction & Building Technology
Zhongyue Zhang, Frank J. Vecchio, Evan C. Bentz, Stephen J. Foster
Summary: Ultra-high-performance fiber-reinforced concrete (UHPFRC) is a material used to solve engineering problems, but the reliability of its finite element modeling has not been assessed. The existing steel fiber-reinforced concrete (SFRC) material models have limited ability in characterizing UHPFRC. This study investigates the existing SFRC material models and improves crack-related formulations and steel reinforcement rupture formulations to enhance the accuracy of the models.
ACI STRUCTURAL JOURNAL
(2022)
Article
Construction & Building Technology
Allan Kuan, Giorgio T. Proestos, Evan C. Bentz, Michael P. Collins
Summary: The experimental investigation of interior beams with integral slabs showed that the strength of these members was significantly underestimated by the ACI 318-19 and CSA A23.3-19 codes. Additionally, there was no significant difference in torsional response between specimens detailed with open stirrups and closed stirrups.
ACI STRUCTURAL JOURNAL
(2021)
Article
Construction & Building Technology
Jack J. Poldon, Neil A. Hoult, Evan C. Bentz
Summary: The use of distributed fiber-optic strain sensors allows for a new level of detail in quantifying and understanding reinforced concrete behavior. This investigation found variations in the behavior of longitudinal and transverse reinforcement bars under different shear demands.
ACI STRUCTURAL JOURNAL
(2021)