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Estimation of modulus of elasticity of compacted loess soil and lateritic-loess soil from laboratory plate bearing test

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CASE STUDIES IN CONSTRUCTION MATERIALS 2022年 16卷

作者： Chindaprasirt, Prinya Sriyoratch, Arkhom Arngbunta, Anukun Chetchotisak, Panatchai Jitsangiam, Peerapong Kampala, Apichit Khon Kaen Univ Fac Engn Sustainable Infrastruct Res & Dev Ctr Dept Civil Engn Khon Kaen Thailand Royal Soc Thailand Acad Sci Bangkok 10300 Thailand Rajamangala Univ Technol Isan Fac Engn Dept Civil Engn Khon Kaen Campus Khon Kaen 40000 Thailand Chiang Mai Univ Fac Engn Ctr Excellence Nat Disaster Management Dept Civil Engn Chiang Mai 50200 Thailand Rajamangala Univ Technol Isan Rail Syst Inst Nakhon Ratchasima 30000 Thailand

In this paper, the moduli of elasticity of compacted loess and lateritic-loess soils on-site were estimated from the laboratory test. These were coarse grain soils used for the construction of base course and embankment of the railway line. The knowledge of the soil properties on-site such as the compacted elastic moduli is essential for the design and selection of materials. A total of 108 samples consisting of 36 samples of compacted soils on-site and 72 samples of compacted soils in laboratory were tested using plate bearing tests. The water contents of the compacted soil on-site were controlled to be within +/- 2% of optimum water content. The water content and density of compacted soil on-site were determined and used for the compaction of soils in the laboratory. For the testing in laboratory, two loading types viz., point load and uniform load were performed using the compacted 15-cm diameter mold (California Bearing Ratio). The results showed that the point load test gave a slightly better estimation of elastic modulus with R-2 of 0.977 than the uniform load test with R-2 of 0.970. The experiment showed that the on-site elastic moduli of loess and lateritic-loess soils could be accurately estimated from the laboratory load tests.

关键词： modulus of elasticity Loess soil Lateritic soil Compaction Plate bearing test

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A Comparison Among Some Non-linear Prediction Tools on Indirect Determination of Uniaxial Compressive Strength and modulus of elasticity of Basalt

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JOURNAL OF NONDESTRUCTIVE EVALUATION 2022年第1期41卷 10-10页

作者： Yesiloglu-Gultekin, N. Gokceoglu, C. Hacettepe Univ Baskent Chamber Ind Organized Ind Zone Vocat Sch Dept Construct Construct Technol Program Ankara Turkey Hacettepe Univ Dept Geol Engn TR-06800 Ankara Turkey

Basalt is among the most used rocks as aggregate, ballast, ornamental stone and for other construction purposes. Therefore, the uniaxial compressive strength (UCS) and elasticity modulus (E-i) of intact rock are required to be known for several purposes. For this reason, the purpose of the present study is to develop various non-linear prediction Model s for UCS and E-i by employing simple and non-destructive test results. Here, a dataset including 137 cases was analyzed. Each case includes unit weight, porosity, sonic velocity, E-i and UCS. The non-linear multiple regression (NLMR), adaptive-neuro fuzzy inference system (ANFIS) and artificial neural networks (ANN) were utilized as non-linear prediction algorithms. The performances of the developed Model s were assessed using various metrics such as coefficient of correlation (R-2), values account for (VAF), root mean squared error (RMSE) and a20-index. To obtain these metrics, a ranking approach was employed. When the metrics were compared, the performance of ANFIS was found slightly higher for the Model s that predict UCS. The ANN was the most successful prediction tool for the Model s predicting E-i. Also, a series of Taylor diagrams were constructed to analyze the Model performances. According to the results, the Model s using porosity and sonic velocity as input parameters for predicting UCS exhibit the highest correlation with the observed data. Regarding the E-i prediction, the Model s with three inputs have the highest performance. The results show that the investigated algorithms reveal comparable performances and the Model s developed here can be used in feasibility assessment stages.

关键词： Basalt Uniaxial compressive strength modulus of elasticity ANFIS ANN Non-linear multiple regression

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Workability, Strength, modulus of elasticity, and Permeability Feature of Wheat Straw Ash-Incorporated Hydraulic Cement Concrete

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BUILDINGS 2022年第9期12卷 1363页

作者： Katman, Herda Yati Binti Khai, Wong Jee Bheel, Naraindas Kirgiz, Mehmet Serkan Kumar, Aneel Khatib, Jamal Benjeddou, Omrane Univ Tenaga Nas Inst Energy Infrastruct Putrajaya CampusJalan IKRAM UNITEN Kajang 43000 Malaysia Univ Teknol PETRONAS Dept Civil & Environm Engn Tronoh 32610 Malaysia Nisantasi Univ Engn Architecture Fac Dept Civil Engn TR-34398 Istanbul Turkey Istanbul Sabahattin Zaim Univ Fac Engn & Nat Sci Dept Architecture TR-34303 Istanbul Turkey Mehran Univ Engn & Technol Dept Civil Engn Jamshoro 76062 Sindh Pakistan Beirut Arab Univ Fac Engn Dept Civil & Environm Engn Beirut 115020 Lebanon Prince Sattam Bin Abdulaziz Univ Coll Engn Dept Civil Engn Alkharj 16273 Saudi Arabia

The extensive use of Portland cement (PC) in the manufacturing of concrete is responsible for the depletion of natural resources that are part of cement production. Cement supply is permanently threatened by the ongoing depletion of natural materials, including sand, limestone, and clay. Concurrently, the incineration of agricultural residues presents a significant ecological problem. This study explores the substitution of cement in concrete with 5%, 10%, 15%, and 20% wheat straw ash as an environmentally friendly alternative. The purpose of this investigation is to evaluate the effect of substituting wheat straw ash (WSA) for PC on the mechanical characteristics of concrete. A total of 75 concrete samples were made by cement or cement + WSA/fine aggregate/coarse aggregate ratio of 1:1, 5:3, and water-to-cement ratio was kept constant at 0.50. All of these specimens were cured and tested at 28 days. The properties tested in the paper were workability, compressive strength, splitting tensile strength, flexural strength, modulus of elasticity, and permeability. The outcomes showed that the substitution of PC with WSA 10% resulted in the greatest concrete strength. In contrast, the mechanical properties and permeability of concrete were reduced when 20% WSA was substituted for PC at 28 days. In addition, the slump value dropped as increasing the content of WSA diminished the weight of PC in the concrete. This could be attributed to the fact that the water content in the WSA 20% concrete was not enough for mechanical strength. Other concretes with WSA showed similar properties to those of the WSA 10% concrete. It was concluded from the results that since the WSA 10% concrete showed the best properties, it can be recommended as the best recipe in this research work.

关键词： energy wheat straw ash-incorporated concrete workability strength modulus of elasticity permeability modelling

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The influence of quartz content on modulus of elasticity and Poisson's ratio in quartz sandstone

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BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT 2022年第7期81卷 287-287页

作者： Sujatono, Supandi Wijaya, Andy Erwin Inst Teknol Nas Yogyakarta Yogyakarta 55281 Indonesia

High content of quartz in various sizes can affect the physical and mechanical properties, in particular the modulus of elasticity and Poisson's ratio. Sandstones are composed of clay-sized to coarse sand-sized quartz minerals, which will affect rock plasticity. The existence of clay-sized sand will certainly have a different impact from the clay-sized material composed of clay minerals. This study aims to determine the influence of quartz mineral content in sandstone on the modulus of elasticity and Poisson's ratio. The analysis was carried out on undisturbed samples of quartz sandstone taken from the Warukin Formation. Uniaxial test was performed on the samples by referring to the ASTM standard. To identify the relationship between the quartz content and the modulus of elasticity as well as Poisson's ratio, simple regression method was implemented. The result shows that quartz content has a very strong correlation with modulus of elasticity in both axial and diametral conditions as well as with Poisson's ratio, indicated by the correlation degree of above 0.90. Each of 1% increase in quartz content is followed by 5% increase in modulus of elasticity in axial condition, 2.4% increase in modulus of elasticity in diametral condition, and 0.84% increase in Poisson's ratio. The elastic modulus increases as the quartz content increases due to the friction among the very heterogeneous quartz minerals (fine to coarse sand in size). When there is pressure, fine-sized quartz will experience deformation and will move to fill the voids so that the sandstone has a high strain.

关键词： Quartz sandstone modulus of elasticity Strain Poisson's ratio

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Study of the relationship between flatwise and edgewise modulus of elasticity of plantation fibre-managed E. nitens sawn boards

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CONSTRUCTION AND BUILDING MATERIALS 2022年 349卷

作者： Hou, Jian Taoum, Assaad Nolan, Gregory Kotlarewski, Nathan Univ Tasmania Sch Engn Hobart Tas 7005 Australia Univ Tasmania Ctr Sustainable Architecture Wood CSAW Launceston Tas 7250 Australia

This study investigated the relationship between flatwise and edgewise modulus of elasticity (MoE) of plantation fibre-managed E. nitens sawn boards. 331 boards were used to build a complete picture of this resource by measuring the density, moisture content, and static edgewise MoE. Then, 147 boards were tested for static flatwise MoE. Results showed that average static flatwise MoE is highly linearly related to static edgewise MoE. The average flatwise MoE could be predicted through the linear relationship considering the contribution of the width of the boards. The R-2 value of this linear regression formula is 0.9.

关键词： E. nitens modulus of elasticity Stiffness Bending test Edgewise MoE Flatwise MoE Visual features

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Assessment of Different Measurement Methods/Techniques in Predicting modulus of elasticity of Plantation Eucalyptus nitens Timber for Structural Purposes

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FORESTS 2022年第4期13卷 607页

作者： Ettelaei, Azin Taoum, Assaad Nolan, Gregory Univ Tasmania Ctr Sustainable Architecture Wood Launceston Tas 7250 Australia Univ Tasmania Sch Engn Coll Sci & Engn Hobart Tas 7005 Australia

The mechanical properties of plantation Eucalyptus Nitens timber are currently assessed by applying visual stress grading (VSG) designed for the sawn timber from the mature plantation and do not represent the actual characteristics of the resource. However, the well-known limitation of VSG application for this resource led to the discovery of other methods to grade the timber to its relevant structural grade. There is potential for hardwood plantations in Australia to supply wood to the timber industry and be used in structural applications. However, it is necessary to employ criteria to evaluate the structural properties of this resource before it could be satisfactorily used for structural purposes. This research aimed to assess the use of non-destructive technique (NDT) through acoustic wave velocity (AWV), machine stress grading (MSG), and multiple linear regression (MLR) model to predict the modulus of elasticity (MOE) as a grade-determining factor. The results showed that there was a strong correlation (R-2 = 0.88) between the dynamic MOE (MOEdyn) and static MOE (MOEs) of the boards, proving the NDT as a reliable method for the MOE estimations of E. nitens timber. The results from the MLR model also showed that the density and AWV are effective parameters and their combination can be practical to estimate the MOE. There was a high correlation between the MOE obtained from MSG and MOE obtained from four-point bending, demonstrating that the MSG method through the flat-wise bending can be a suitable method for fast grading. The results also indicated that the measured MOE in the edgewise direction correlates with both the flatwise and longitudinal directions. The results also showed that the E. nitens timber resource has the potential to be used in structural applications with a wide range of MOE from 7 GPa to 21 GPa.

关键词： Eucalyptus nitens structural applications hardwood plantation structural grading modulus of elasticity

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Estimation of temperature-dependent yield strength and modulus of elasticity during laser bending

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MEASUREMENT 2020年第0期154卷 107515-000页

作者： Kumar, Vikash Dixit, Uday S. Indian Inst Technol Guwahati Dept Mech Engn Gauhati 781039 Assam India

In this work, an inverse method is developed to estimate the temperature-dependent value of yield strength (Y) and modulus of elasticity (E) of the material during a laser bending process. The method requires measurement of bend angle of the laser scanned workpiece. The inverse model uses the bend angle computed by a direct model. The temperature-dependent Y and E are inversely estimated by minimizing the difference between actual and direct model predicted bend angles. The validation of the proposed method is demonstrated with the help of two examples. For this purpose, inversely estimated values of E and Y are used to predict bend angles for various processing conditions and predicted values are compared with actual values. In examples, actual data has been obtained from a detailed FEM simulation in lieu of shop floor experiments. Later on, the proposed method is also validated by performing shop floor experiments for AH36 steel. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Laser bending Finite element method Inverse technique Yield strength modulus of elasticity

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ANALYSIS OF modulus of elasticity OF SPRUCE BEAMS UNDER BENDING WITH AND WITHOUT FIBRE REINFORCEMENT

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WOOD RESEARCH 2020年第1期65卷 101-110页

作者： Andor, Krisztian Bellovics, Bertalan Univ Sopron Fac Simonyi Karoly Tech Wood Sci & Art Inst Appl Mech & Struct Bajcsy Zs EU 4 H-9400 Sopron Hungary

The modulus of elasticity has been assumed constant during the finite element (FE) analysis of CFRP reinforced real sized timbers analyzed in load test in laboratory. The latest investigations have shown that it varies significantly during the loading process. Analysis of the modulus of elasticity during the loading provides answers to several questions, by which the FE analysis can be profoundly optimized and yield more accurate estimates. Analysis has been extended to load-modulus functions of previous investigations. Specimens without reinforcement were also included in the investigations, in order to eliminate anomalies of previous measurements and to get easier comparison.

关键词： Carbon fibre reinforcement beam modulus of elasticity load-bearing four-point bending

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Investigations on modulus of elasticity of aluminium reinforced 3D printed structures

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Materials Today: Proceedings 2022年 48卷 1055-1058页

作者： Piyush Raman Kumar Ranvijay Kumar Department of Mechanical Engineering Chandigarh University Mohali 140413 India University Centre for Research and Development Chandigarh University Mohali 140413 India

Reinforcements in polymers provide the modification over mechanical properties. In this study, aluminium (Al) is reinforced with acrylonitrile butadiene styrene (ABS) using spraying technique and hybrid composite samples were prepared. Input parameters used in study are infill density (60%, 80%, 100%), infill pattern (linear, triangular, cubic) and number of Al layers (2, 3, 4). Samples were prepared according to ASTM D638 type IV standards and subjected to tensile testing. Considering 4 aluminium sprayed layers, 100% infill density and linear infill pattern, it has been resulted into maximum modulus of elasticity of prepared specimen. It has been observed that number of aluminium layers sprayed is the most influencing factor for modulus of elasticity. Optimized printing parameters were established at 3 no. of aluminium layers, 100% infill density with linear pattern.

关键词： Reinforced polymers 3D printing modulus of elasticity ABS FDM

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modulus of elasticity and Poisson's ratio of fiber-reinforced concrete in Colombia from ultrasonic pulse velocities

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JOURNAL OF BUILDING ENGINEERING 2019年 23卷 18-26页

作者： Carrillo, Julian Ramirez, Julieth Lizarazo-Marriaga, Juan Nueva Granada Mil Univ UMNG Dept Civil Engn Bogota Colombia Nueva Granada Mil Univ UMNG Struct & Earthquakes Res Grp Bogota Colombia Univ Nacl Colombia Dept Civil & Environm Engn Bogota Colombia

modulus of elasticity and Poisson's ratio are the main mechanical properties of concrete for assessing the flexural and shear stiffness of concrete elements. Although steel fibers are beginning to be accepted in modern building codes, equations for estimating the elasticity modulus and Poisson's ratio of Fiber Reinforced Concrete (FRC) are not provided in such building codes. Even though the direct measurement of the modulus of elasticity and the Poisson's ratio is adequately established, the use of non-destructive methods such the Ultrasonic Pulse Velocity (UPV) test offers an economical and easy alternative that must be explored. The aim of this paper is to propose empirical relationships for estimating the dynamic modulus of elasticity and Poisson's ratio of concrete reinforced with steel, synthetic and hybrid fibers, using results measured during the UPV tests. The research is also intended to assess results of models reported in a literature review, to evaluate the effect of test setup (direct, semi-direct and direct), and to establish a relationship between the dynamic modulus of elasticity of FRC and the characteristics of steel, polypropylene/polyethylene and hybrid fibers. The experimental program included dynamic non-destructive tests and static destructive tests of 29 concrete specimens. The variables included in the experimental program were the fiber type (steel, synthetic and hybrid), the fiber content and the ultrasonic pulse velocity setup (direct and semi-direct). The length, diameter and aspect ratio of fibers were 50 mm, 1.05mm and 48 for the steel fibers, and 50 mm, 0.68mm and 74 for the polypropylene/polyethylene synthetic fibers. Fiber volume fractions in the concrete varied between 0.17% and 0.93%. The study also compared the results obtained in the static tests with the dynamic results, in order to identify the differences between static and dynamic behavior.

关键词： Fiber reinforced concrete modulus of elasticity Poisson's ratio Non-destructive test Ultrasonic pulse velocity test

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