Machine learning techniques for reinforced concrete’s tensile strength assessment under different wetting and drying cycles

Ibrahim AlBaijan,Danial Fakhri,Adil Hussein Mohammed,Arsalan Mahmoodzadeh,Hawkar Hashim Ibrahim,Khaled Mohamed Elhadi,Shima Rashidi 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.49 No.3

Successive wetting and drying cycles of concrete due to weather changes can endanger the safety of engineering structures over time. Considering wetting and drying cycles in concrete tests can lead to a more correct and reliable design of engineering structures. This study aims to provide a model that can be used to estimate the resistance properties of concrete under different wetting and drying cycles. Complex sample preparation methods, the necessity for highly accurate and sensitive instruments, early sample failure, and brittle samples all contribute to the difficulty of measuring the strength of concrete in the laboratory. To address these problems, in this study, the potential ability of six machine learning techniques, including ANN, SVM, RF, KNN, XGBoost, and NB, to predict the concrete’s tensile strength was investigated by applying 240 datasets obtained using the Brazilian test (80% for training and 20% for test). In conducting the test, the effect of additives such as glass and polypropylene, as well as the effect of wetting and drying cycles on the tensile strength of concrete, was investigated. Finally, the statistical analysis results revealed that the XGBoost model was the most robust one with R2 = 0.9155, mean absolute error (MAE) = 0.1080 Mpa, and variance accounted for (VAF) = 91.54% to predict the concrete tensile strength. This work’s significance is that it allows civil engineers to accurately estimate the tensile strength of different types of concrete. In this way, the high time and cost required for the laboratory tests can be eliminated.

Application of computer methods for the effects of nanoparticles on the frequency of the concrete beams experimentally and numerically

Chencheng Song,Junfeng Shi,Ibrahim AlBaijan,H. Elhosiny Ali,Amir Behshad 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.48 No.1

Due to high application of concrete structures in construction industry, however, the quality improvement is essential. One of the new ways for this purpose is adding the nanoparticles to the concrete. In this work, vibration analysis of concrete beams reinforced by graphene oxide (GO) nanoparticles based on mathematical model has been investigated. For the accuracy of the presented model, the experimental study is done for comparing the compressive strength. Since the nanoparticles can not be solved in water without any specific process, at the first, GO nanoparticles should be dispersed in water by using shaker, magnetic striker, ultrasonic devices and finally mechanical mixer. For modelling of the strucuture, sinusoidal shear deformation beam theory (SSDBT) is utilized. Mori-Tanak model model is utilized for obtaining the effective properties of the beam including agglomeration influences. Utilizing the energy method and Hamilton’s principal, the motion equations are calculated. The frequency of the concrete beam is obtanied by analytical method. Three samples with 0.02% GO nanoparticles are built and its compressive strength is compared which shows a good accuracy with maximum 1.29% difference with mathematical model and other papers. The aim of this work from the theoretical study is investigating the effects of nanoparticles volume percentage and agglomeration, length and thickness of the beam on the frequency of the structure. The results show that the with enhancing the GO nanoparticles, the frequency is increased. For example, with enhancing the volume percent of GO nanoparticles from zero to 0.08%, the compressive strength is increased 48.91%. and 46.83%, respectively for two cases of with and without agglomeration.

Optimization of the cross-section regarding the stability of nanostructures according to the dynamic analysis

Qiuyang Cheng,H. Elhosiny Ali,Ibrahim Albaijan Techno-Press 2023 Advances in concrete construction Vol.15 No.4

The vibrational behavior of nanoelements is critical in determining how a nanostructure behaves. However, combining vibrational analysis with stability analysis allows for a more comprehensive knowledge of a structure's behavior. As a result, the goal of this research is to characterize the behavior of nonlocal nanocyndrical beams with uniform and nonuniform cross sections. The nonuniformity of the beams is determined by three distinct section functions, namely linear, convex, and exponential functions, with the length and mass of the beams being identical. For completely clamped, fully pinned, and cantilever boundary conditions, Eringen's nonlocal theory is combined with the Timoshenko beam model. The extended differential quadrature technique was used to solve the governing equations in this research. In contrast to the other boundary conditions, the findings of this research reveal that the nonlocal impact has the opposite effect on the frequency of the uniform cantilever nanobeam. Furthermore, since the mass of the materials employed in these nanobeams is designed to remain the same, the findings may be utilized to help improve the frequency and buckling stress of a resonator without requiring additional material, which is a cost-effective benefit.

TiO₂-containing nanocomposite structure: Application and investigation in shoes sports medical soles in physical activities

Xufei Li,H. Elhosiny Ali,Ibrahim Albaijan Techno-Press 2023 Advances in nano research Vol.15 No.4

Wearing the right sportswear is one of the essential points in exercising, which is mainly neglected. Sportswear should be suitable for the ambient temperature and not cause more heat or cold in the athlete's body. On the other hand, increased sweating and blood circulation during exercise should not cause fatigue or heatstroke in the athlete. Nanotechnology has grown significantly in the field of producing more efficient equipment in the field of sports. The increase in demand in sports for complete sports equipment has revealed the necessity of using the highest quality materials in this sector. In the world of championship sports, a minor change in equipment can lead to significant changes in causing failure and victory. Since the sole is the most critical part of sports shoes, with the introduction of nanotechnology and nanocomposites, it is possible to help athletes rush and increase their sense of calm and satisfaction. Using nanocomposites in the soles of shoes can improve some of their characteristics, prevent the smell and sweat of shoes, and induce water repellency in these shoes. In this research, titanium dioxide (TiO₂) nanocomposite, along with cellulose, has been used to create antibacterial and hydrophobic properties in the soles of sports shoes. The synthesized nanocomposite has been synthesized using the least amount of chemicals, which shows this method's easy and cost-effective synthesis.

The gene expression programming method to generate an equation to estimate fracture toughness of reinforced concrete

Ahmadreza Khodayari,Danial Fakhri,Adil Hussein Mohammed,Ibrahim AlBaijan,Arsalan Mahmoodzadeh,Hawkar Hashim Ibrahim,Ahmed Babeker Elhag,Shima Rashidi 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.48 No.2

Complex and intricate preparation techniques, the imperative for utmost precision and sensitivity in instrumentation, premature sample failure, and fragile specimens collectively contribute to the arduous task of measuring the fracture toughness of concrete in the laboratory. The objective of this research is to introduce and refine an equation based on the gene expression programming (GEP) method to calculate the fracture toughness of reinforced concrete, thereby minimizing the need for costly and time-consuming laboratory experiments. To accomplish this, various types of reinforced concrete, each incorporating distinct ratios of fibers and additives, were subjected to diverse loading angles relative to the initial crack (α) in order to ascertain the effective fracture toughness (Keff) of 660 samples utilizing the central straight notched Brazilian disc (CSNBD) test. Within the datasets, six pivotal input factors influencing the Keff of concrete, namely sample type (ST), diameter (D), thickness (t), length (L), force (F), and α, were taken into account. The ST and α parameters represent crucial inputs in the model presented in this study, marking the first instance that their influence has been examined via the CSNBD test. Of the 660 datasets, 460 were utilized for training purposes, while 100 each were allotted for testing and validation of the model. The GEP model was finetuned based on the training datasets, and its efficacy was evaluated using the separate test and validation datasets. In subsequent stages, the GEP model was optimized, yielding the most robust models. Ultimately, an equation was derived by averaging the most exemplary models, providing a means to predict the Keff parameter. This averaged equation exhibited exceptional proficiency in predicting the Keff of concrete. The significance of this work lies in the possibility of obtaining the Keff parameter without investing copious amounts of time and resources into the CSNBD test, simply by inputting the relevant parameters into the equation derived for diverse samples of reinforced concrete subject to varied loading angles.

Static analysis of 2D-FG nonlocal porous tube using gradient strain theory and based on the first and higher-order beam theory

Xiaozhong Zhang,Jian-Feng Li,Yan Cui,Mostafa Habibi,H. Elhosiny Ali,Ibrahim AlBaijan,Tayebeh Mahmoudi 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.49 No.3

This article focuses on the study of the buckling behavior of two-dimensional functionally graded (2D-FG) nanosize tubes, including porosity, based on the first shear deformation and higher-order theory of the tube. The nano-scale tube is simulated using the nonlocal gradient strain theory, and the general equations and boundary conditions are derived using Hamilton’s principle for the Zhang-Fu’s tube model (as a higher-order theory) and Timoshenko beam theory. Finally, the derived equations are solved using a numerical method for both simply-supported and clamped boundary conditions. A parametric study is performed to investigate the effects of different parameters, such as axial and radial FG power indices, porosity parameter, and nonlocal gradient strain parameters, on the buckling behavior of the bi-dimensional functionally graded porous tube. Keywords: Nonlocal strain gradient theory; buckling; Zhang-Fu’s tube model; Timoshenko theory; Two-dimensional functionally graded materials; Nanotubes; Higher-order theory.

Predicting the splitting tensile strength of manufactured-sand concrete containing stone nano-powder through advanced machine learning techniques

Manish Kewalramani,Hanan Samadi,Adil Hussein Mohammed,Arsalan Mahmoodzadeh,Ibrahim Albaijan,Hawkar Hashim Ibrahim,Saleh Alsulamy Techno-Press 2024 Advances in nano research Vol.16 No.4

The extensive utilization of concrete has given rise to environmental concerns, specifically concerning the depletion of river sand. To address this issue, waste deposits can provide manufactured-sand (MS) as a substitute for river sand. The objective of this study is to explore the application of machine learning techniques to facilitate the production of manufactured-sand concrete (MSC) containing stone nano-powder through estimating the splitting tensile strength (STS) containing compressive strength of cement (CSC), tensile strength of cement (TSC), curing age (CA), maximum size of the crushed stone (Dmax), stone nano-powder content (SNC), fineness modulus of sand (FMS), water to cement ratio (W/C), sand ratio (SR), and slump (S). To achieve this goal, a total of 310 data points, encompassing nine influential factors affecting the mechanical properties of MSC, are collected through laboratory tests. Subsequently, the gathered dataset is divided into two subsets, one for training and the other for testing; comprising 90% (280 samples) and 10% (30 samples) of the total data, respectively. By employing the generated dataset, novel models were developed for evaluating the STS of MSC in relation to the nine input features. The analysis results revealed significant correlations between the CSC and the curing age CA with STS. Moreover, when delving into sensitivity analysis using an empirical model, it becomes apparent that parameters such as the FMS and the W/C exert minimal influence on the STS. We employed various loss functions to gauge the effectiveness and precision of our methodologies. Impressively, the outcomes of our devised models exhibited commendable accuracy and reliability, with all models displaying an R-squared value surpassing 0.75 and loss function values approaching insignificance. To further refine the estimation of STS for engineering endeavors, we also developed a user-friendly graphical interface for our machine learning models. These proposed models present a practical alternative to laborious, expensive, and complex laboratory techniques, thereby simplifying the production of mortar specimens.

Effect of perlite powder on properties of structural lightweight concrete with perlite aggregate

Gongxing Yan,Mohammed Zuhear Al-Mulali,Amirhossein Madadi,Ibrahim Albaijan,H. Elhosiny Ali,H. Algarni,Binh Nguyen Le,Hamid Assilzadeh 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.84 No.3

A high-performance reactive powder concrete (RPC) has been readied alongside river sand, with 1.25 mm particle size when under the condition of 80C steam curing. As a heat and sound insulation, expanded perlite aggregate (EPA) provides economic advantages in building. Concrete containing EPA is examined in terms of cement types (CEM II 32.5R and CEM I 42.5R), doses (0, 2%, 4% and 6%) as well as replacement rates in this research study. The compressive and density of concrete were used in the testing. At the end of the 28-day period, destructive and nondestructive tests were performed on cube specimens of 150 mm150 mm150 mm. The concrete density is not decreased with the addition of more perlite (from 45 to 60 percent), since the enlarged perlite has a very low barrier to crushing. To get a homogenous and fluid concrete mix, longer mixing times for all the mix components are necessary due to the higher amount of perlite. As a result, it is not suggested to use greater volumes of this aggregate in RPC. In the presence of de-icing salt, the lightweight RPC exhibits excellent freeze-thaw resistance (mass is less than 0.2 kg/m2). The addition of perlite strengthens the aggregate-matrix contact, but there is no apparent ITZ. An increased compressive strength was seen in concretes containing expanded perlite powder and steel fibers with good performance.

Mechanical and corrosion resistant properties of ATIG welded 2205 duplex stainless-steel via different fluxes

Hussein Alrobei,Kamel Touileb,Rachid Djoudjou,Abousoufiane Ouis,Abdeljlil Chihaoui Hedhibi,Ibrahim AlBaijan,Rizwan Ahmed Malik,El-Sayed M. Sherif 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.12

In this study, 6 mm thick duplex stainless-steel grade 2205 plate was welded by active tungsten inert gas (ATIG) using different oxide fluxes and the effect of optimal oxide fluxes on structure, mechanical and corrosion properties was systematically analyzed and discussed. Initially, fourteen oxides were tested (SiO 2 , TiO 2 , ZnO, MnO 2 , Cr 2 O 3 , Fe 2 O 3 , ZrO 2 , SrO, CaO, MoO 3 , V 2 O 5 , Mn 2 O 3 , Co 2 O 3 and MgO). Among these, three candidate oxides, i.e., SiO 2 , Ti 2 O and ZnO were selected for further evaluation based on the depth ratio, depth-to-width (D/W), and ultimate tensile strength (UTS) results. By using Minitab 17 software, optimal combinations of these fluxes for maximum penetrations were estimated. The obtained results revealed that the optimal flux composition is 76 % SiO 2 -24 % ZnO. The results showed that the depth attained by the optimized flux is 2.9 times greater than tungsten inert gas (TIG) weld. The D/W ratio was also improved 3.7 times when contrasted with typical TIG welding. The energy absorbed in fusion zone in the case of ATIG weld is greater when contrasted with TIG weld. It was found that the weld bead obtained with optimal flux combination in ATIG weld can better withstand sudden loads. The obtained UTS value (810 MPa) for ATIG weld was close to parent metal (825 MPa) and greater than the weld produced by TIG welding (766 MPa). However, the corrosion resistant property was found to be slightly decreased for metal welded with ATIG as compared to metal welded by using TIG. These results give a comprehensive guideline for further investigations on TIG welding of 2205 duplex stainless-steel.

Geometry impact on the stability behavior of cylindrical microstructures: Computer modeling and application for small-scale sport structures

Yunzhong Dai,Zhiyong Jiang,Kuan-yu Chen,Duquan Zuo,Mostafa Habibi,H. Elhosiny Ali,Ibrahim AlBaijan 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.48 No.4

This paper investigates the stability of a bi-directional functionally graded (BD-FG) cylindrical beam made of imperfect concrete, taking into account size-dependency and the effect of geometry on its stability behavior. Both buckling and dynamic behavior are analyzed using the modified coupled stress theory and the classical beam theory. The BD-FG structure is created by using porosity-dependent FG concrete, with changing porosity voids and material distributions along the pipe radius, as well as uniform and nonuniform radius functions that vary along the beam length. Energy principles are used to generate partial differential equations (PDE) for stability analysis, which are then solved numerically. This study sheds light on the complex behavior of BD-FG structures, and the results can be useful for the design of stable cylindrical microstructures.