Beam Sampling Research Articles

BEARING CAPACITY, DEFORMABILITY AND CRACK RESISTANCE OF A DAMAGED BEAM REINFORCED WITH FIBER CONCRETE IN THE COMPRESSED ZONE

The paper presents the results of the study of the load-bearing capacity, deformability and crack resistance of a damaged beam reinforced with fiber concrete in the compressed zone. A beam with 40% damage is considered. The research was conducted in two stages. At the first stage, tests of prisms and cubes made of concrete and fiber concrete were carried out, which showed that the introduction of steel fiber into the composition of concrete in the amount of 2% by volume increases the compressive strength by 15.3%. The initial modulus of elasticity of fiber concrete of the specified mixture is 38.0% higher than that of ordinary concrete of this composition. According to the results of experimental studies of prisms, a diagram of concrete deformation, the nature of changes in relative linear deformations of fiber concrete, as well as graphs showing a comparison of the nature of deformation of concrete and fiber concrete were constructed. At the second stage, the beam sample was tested on a specially designed stand. Before concreting, a foam insert was installed in the zone of planned damage, the shape and dimensions of which corresponded to the planned damage. After the concrete set to 70% strength, the liner was removed, and the formed cavity was filled with a 2% fiber concrete mixture. A beam with 40% cross-sectional damage in the mid-compression zone and a near-rectangular damage shape was found to have a load-bearing capacity of 92.0 kN, or 93.9% of the load-bearing capacity of an undamaged beam. Cracking started at the 4th loading stage, when the load value was 26.0kN, i.e. 28.3% of the bearing capacity of the damaged beam. At the same time, 5 cracks formed in the area of pure bending. At the fifth stage, two more cracks appeared. At the 8th and 9th loading stages, 4 more cracks formed. A total of 12 cracks were formed. The maximum final crack opening width was 0.6 mm. Thus, the strengthening of a beam with 40% damage in the compressed zone by the method considered in the work allows you to achieve its bearing capacity, which is 93.9% of the bearing capacity of an intact beam.

Interleaving Carbon-Glass Veil in Glass Epoxy Composite for Improved Mode-I Fracture Toughness – A Hybrid Approach

The present study investigates the influence of hybrid interleaving technique using Glass and Carbon veils to improve the mode-I fracture toughness in Glass epoxy laminates. Commercially available non-woven Carbon and Glass veils with different areal densities were used to develop hybrid interleaved composites. Two approaches of interleaving, namely inter-ply and inter-weaved veils, were followed to manufacture the interleaved composite laminates using the hand layup technique. Double Cantilever Beam (DCB) samples were tested to estimate the interlaminar fracture toughness (IFT). Test results indicate that the inter-ply interleaved composite (I-C30G30) exhibited an improved initial and propagation fracture toughness of about 16.98% and 3.08%, respectively. A decreased IFT during initiation and propagation was observed for I-C15G30 and I-C20G30 when compared to plain samples. In case of inter-weaved veil interleaving approach, an improved fracture toughness (GIC and GIP) of about 7.96% and 12.94%, respectively, was observed for W-C15G30 sample, nevertheless W-C20G30 and W-C30G30 showed a drop in fracture toughness (GIC) of an about 12.15% and 9.22%, respectively, and an improvement in fracture toughness (GIP) of about 12.37% and 13.82%, respectively, when compared to plain sample. Scanning electron photo images (SEPI) of cracked laminates witnessed the fracture mechanisms involved in hybrid ply interleaved and non-interleaved composite laminates.

Prediction of the Physical-Mechanical Properties of Roller-Compacted Concrete Pavements under Different Service and Mix Conditions Based on Cement and Water Content.

Roller-compacted concrete (RCC) for pavements has experienced problems with its physical-mechanical performance over extended periods due to ambient and in situ curing conditions. Accordingly, this study aimed to present multiple regression equations for calculating the physical-mechanical properties of RCC for pavements under different service and mix conditions. For this purpose, the research included two cement and two water contents, one reduced with admixture, and four combinations of temperature and relative humidity. For model calibration and definition of the equations, cubic and beam samples were fabricated to carry out physical-mechanical tests, such as moisture content, shrinkage, and modulus of rupture. Laboratory-obtained data were studied with the Response Surface Methodology (RSM) to determine the best regression equations. The main findings determined that the behavior of a mixture of RCC at a prolonged ambient exposure time is possible because the surface models and the RSM were consistent with the different service and mix conditions. The models showed an accuracy of 98.99% in detecting shrinkage changes from 12 to 16% cement with 5.65% water in dry to wet ambient conditions. Similarly, moisture content and modulus of rupture had a 98.27 to 98.88% fit. Finally, the drying shrinkage, with mixes of 12% cement and water content variations with water-reducing admixture and superplasticizer effects, had an adjustment of 94.87%.

SONGS CONTINUATION GENERATION TECHNOLOGY BASED ON TEST GENERATION STRATEGIES, TEXTMINING AND LANGUAGE MODEL T5

Context. Pre-trained large language models are currently the driving force behind the development of not only NLP, but also deep learning systems in general. Model transformers are able to solve virtually all problems that currently exist, provided that certain requirements and training practices are met. In turn, words, sentences and texts are the basic and most important way of communication between intellectually developed beings. Of course, speech and texts are used to convey certain emotions, events, etc. One of the main ways of using language to describe experienced emotions is songs with lyrics. However, often due to the need to preserve rhyme and rhyming, the dimensions of verse lines, song structure, etc., artists have to use repetition of lines in the lyrics. In addition, the process of writing texts can be long.
 Objective of the study is to develop information technology for generating the continuation of song texts based on the T5 machine learning model with (SA, specific author) and without (NSA, non-specific author) consideration of the author's style.
 Method. Choosing a decoding strategy is important for the generation process. However, instead of favoring a particular strategy, the system will support multiple strategies. In particular, the following 8 strategies: Contrastive search, Top-p sampling, Top-k sampling, Multinomial sampling, Beam search, Diverse beam search, Greedy search, and Beam-search multinomial sampling.
 Results. A machine learning model was developed to generate the continuation of song lyrics using large language models, in particular the T5 model, to accelerate, complement and increase the flexibility of the songwriting process.
 Conclusions. The created model shows excellent results of generating the continuation of song texts on test data. Analysis of the raw data showed that the NSA model has less degrading results, while the SA model needs to balance the amount of text for each author. Several text metrics such as BLEU, RougeL and RougeN are calculated to quantitatively compare the results of the models and generation strategies. The value of the BLEU metric is the most variable, and its value varies significantly depending on the strategy. At the same time, Rouge metrics have less variability, a smaller range of values. For comparison, 8 different decoding methods for text generation, supported by the transformers library, were used. From all the results of the text comparison, it is clear that the metrically best method of song text generation is beam search and its variations, in particular beam sampling. Contrastive search usually outperformed the conventional greedy approach. The top-p and top-k methods are not clearly superior to each other, and in different situations gave different results.

External standard calibration method for high-repetition-rate shock tube kinetic studies with synchrotron-based time-of-flight mass spectrometry.

The signal levels observed from mass spectrometers coupled by molecular beam sampling to shock tubes are impacted by dynamic pressures in the spectrometer due to rapid pressure changes in the shock tube. Accounting for the impact of the pressure changes is essential if absolute concentrations of species are to be measured. Obtaining such a correction for spectrometers operated with vacuum ultra violet photoionization has been challenging. We present here a new external calibration method which uses VUV-photoionization of CO2 to develop time-dependent corrections to species concentration/time profiles from which kinetic data can be extracted. The experiments were performed with the ICARE-HRRST (high repetition rate shock tube) at the DESIRS beamline of synchrotron SOLEIL. The calibration experiments were performed at temperatures and pressures behind reflected shock waves of 1376 ± 12 K and 6.6 ± 0.1 bar, respectively. Pyrolytic experiments with two aromatic species, toluene (T5 = 1362 ± 22 K, P5 = 6.6 ± 0.2 bar) and ethylbenzene (T5 = 1327 ± 18 K, P5 = 6.7 ± 0.2 bar), are analyzed to test the method. Time dependent concentrations for molecular and radical species were corrected with the new method. The resulting signals were compared with chemical kinetic simulations using a recent mechanism for pyrolytic formation of polycyclic aromatic hydrocarbons. Excellent agreement was obtained between the experimental data and simulations, without adjustment of the model, demonstrating the validity of the external calibration method.

Experimental and Statistical Study of Flexural Strength in Concrete using Novel Kaolinite Coal

The purpose of this research is to measure the flexural strength of both traditional and newly modified concrete beams with kaolinite coal added. Two sets of eighteen samples each were ready for the data collection. Two sets of specimensare prepared: 18 specimens of one set using modified concrete that has been treated with kaolinite coal, and the other set of 18 specimens using traditional concrete beams. The preparation and examination of the samples involved the use of flexural strength test equipment. The beam specimen size was taken as 100 x 100 x 500mm. The SPSS software version 29 has been utilized to conduct the independent sample T-test. The statistical analysis included Levene's test for equality of variances and a t-test for equality of means to assess the flexural strength of two groups. Levene's test revealed a significant difference in variances between the groups (F=2.909, p=0.097). Subsequently, the t-test assuming equal variances indicated a highly significant difference in means (t=-16.954, df=34, p=0.000). The mean difference in flexural strength was -1.43578, with a standard error of 0.08469 and a 95% confidence interval ranging from -1.60788 to -1.26367. The t-test assuming unequal variances corroborated the significant difference in means (t=-16.954, df=29.822, p=0.000), with a consistent mean difference and confidence interval. The modified concrete beam sample with kaolinite coal added has a mean flexural strength of 4.75 N/mm2, while the standard concrete beam sample has a mean flexural strength of 2.73 N/mm2.

NUMERICAL AND ANALYTICAL INVESTIGATION OF THE J-INTEGRAL VALUE IN A DOUBLE CANTILEVER BEAM SAMPLE WITH AN EXTREMELY THIN ELASTIC-PLASTIC ADHESION LAYER

The loading of a double cantilever beam sample, which is a composition of cantilevers and an adhesive layer, is considered, which leads to deformation of the layer by normal rupture. The basis of the mathematical model describing the equilibrium of the composite is the variational equilibrium equation connecting the stresses averaged over the thickness of the layer and the stress-strain state of the cantilever by a linear parameter. The behavior of the cantilever is considered within the framework of a linearly elastic body, the adhesive layer is considered elastic-plastic without hardening. The composite is considered in a state of plane deformation. Assuming the fulfillment of the condition of complete plasticity of the equality of two principal stresses acting orthogonally to separation and elastic volumetric deformation, the constitutive relations of the behavior of the layer at the stage of elastoplastic deformation are obtained. Using the distribution of the displacement field according to the theory of Mindlin-Reisner plates, a system of ordinary differential equations, conjugation conditions for solutions, and boundary conditions are obtained from the variational formulation of the problem. It is shown that, depending on the ratio of the linear parameter and the height of the console, the characteristic equation of the corresponding homogeneous system of differential equations has both real and complex roots. The corresponding general solutions of the system are found. Based on the consideration of one region of elastoplastic deformations, an iterative procedure for finding the length of the plastic zone is proposed, taking into account the satisfaction of boundary conditions. From the solution of the problem for a given value of the linear parameter and a critical external load, the stress-strain state of the layer is found, on the basis of which the J-integral is calculated. It is shown that as the linear parameter tends to zero, the J-integral asymptotically tends to the value found in the framework of the linearly elastic behavior of the layer material. For a certain range of values of the linear parameter, the obtained solution was compared with the finite element solution of the 2D problem.

Experimental and Statistical Study of Flexural Strength in Concrete using Novel Kaolinite Coal

The purpose of this research is to measure the flexural strength of both traditional and newly modified concrete beams with kaolinite coal added. Two sets of eighteen samples each were ready for the data collection. Two sets of specimensare prepared: 18 specimens of one set using modified concrete that has been treated with kaolinite coal, and the other set of 18 specimens using traditional concrete beams. The preparation and examination of the samples involved the use of flexural strength test equipment. The beam specimen size was taken as 100 x 100 x 500mm. The SPSS software version 29 has been utilized to conduct the independent sample T-test. The statistical analysis included Levene’s test for equality of variances and a t-test for equality of means to assess the flexural strength of two groups. Levene's test revealed a significant difference in variances between the groups (F=2.909, p=0.097). Subsequently, the t-test assuming equal variances indicated a highly significant difference in means (t=-16.954, df=34, p=0.000). The mean difference in flexural strength was -1.43578, with a standard error of 0.08469 and a 95% confidence interval ranging from -1.60788 to -1.26367. The t-test assuming unequal variances corroborated the significant difference in means (t=-16.954, df=29.822, p=0.000), with a consistent mean difference and confidence interval. The modified concrete beam sample with kaolinite coal added has a mean flexural strength of 4.75 N/mm2, while the standard concrete beam sample has a mean flexural strength of 2.73 N/mm2.

Determination of the Strength Characteristics of Sporosarcinal -PasteuriiConcrete

The strength characteristics ofSporosarcinal Pasteuriiconcrete (S. Pasteurii concrete)was investigated.To achieve this aim, the suitability of the materials used for concrete specimens weretested before the compressive, tensile and flexural strength of the S.Pasteurii concrete was investigated.Bacteria concentration of 0, 0.5, 2, 4 and 6OD was mix with the concrete. The water cement ratio adapted was 0.5.For the compressive strength, three cubes of size 150 x 150 x150mm was crushed for each curing day of 1, 3, 7,14, 28 and 56 days. The average compressive strength was obtained as the compressive strength of the concrete at eachcuring age. For the split tensile strength, three cylindrical specimen of size 100mm x 200mm was used at each day to obtain the strength at 7, 14, 21 and 28 days. The average tensile strength was obtained and for the flexural strength, three beam samples of 100 x 100 x 450mm was used at each curing day of 7, 14, 21 and 28days to obtain the average flexural strength.All the properties of the materials used for the concrete production met the standard requirement of the relevant code of practice. The compressive, tensile and flexural strength of S. Pasteurii concrete was improved in comparison with the control concrete. The percentage increase of the compressive strength at 28days are 17.76%, 19.72%, 25% and 4.04% for 0.5OD, 2OD, 4OD and 6OD respectively.The highest tensile strength was increased by 16.24% and obtained when 0.5OD bacteria concentration was used and cured for 14days. The flexural strength of S. Pasteurii concrete was improved by 44.44%, 8.89%,47.40% and 8.52% for 0.5OD, 2OD,4OD and 6OD respectively at 28 day of curing.

DEFORMABILITY AND CRACK RESISTANCE OF REINFORCED CONCRETE AND FIBER CONCRETE BEAMS

The work presents the results of the study of deformability and crack resistance of reinforced concrete beams with additional steel fiber reinforcement. Beam samples of three series were produced (three in each series): series I ― beams made of ordinary concrete; II series ― steel-reinforced concrete beams; III series ― beams of combined section, in which the lower zone (0.5 from the height of the beam) is made of steel fiber concrete, and the upper zone is made of ordinary concrete. One sample of each series was made from one batch. At the same time, material samples were made from the same batch. Fiber, the total volume of which was 1% of the volume, was uniformly added to the composition of the concrete mass for the II and III series of samples during mixing. The load was applied in increments of 1 ton. Deformations were determined using strain gauges, watch-type indicators with a division value of 0.01 mm in the middle of the beam span. At each stage, a certain amount of time was required to read the instruments, find and fix the cracks, as well as to measure the length and width of their opening using a Brinell tube. The tests showed that the deformability of the beams of the three series and the character of the crack formation are significantly different from each other. Moreover, the series III beam with combined reinforcement occupies an intermediate position in terms of these characteristics. Thus, by the end of the tests, the reinforced concrete beam (series I) had 19 cracks, the fiber concrete beam (series II) ― 28, the beams with combined reinforcement (series III) ― 23. At the same time, the maximum final crack opening width for beams I, II, III series was 0.8 mm, 0.1 mm (one crack) and 0.1 mm (two cracks), respectively. Cracks in a fiber concrete beam are much smaller in width. And the maximum length of the cracks here turned out to be the largest ― 31.3 cm, while in the beams of the I and III series this value was 25.5 cm and 20.4 cm, respectively.
 The analysis of the given results shows that the best indicators of crack resistance are revealed by beams with full dispersion reinforcement. The use of fiber allows you to change the nature of the destruction process. Unlike ordinary concrete, in which this process occurs almost instantaneously, in fiber concrete there is no brittle failure, and the beam continues to resist the load, and the nature of the failure changes from brittle to viscous.

(Invited) The Laser-Integrated FIB-SEM for Faster 3D Packages Characterization and Failure Analysis

The semiconductor industry is constantly looking for new technologies and materials to provide more functionality and performance in a smaller volume.Modern innovations in the development of 3D advance packaging require new methods of materials research and failure analysis. Three-dimensional multi-level electronic components, whose packages contain a stack of chips and interconnections, require visualization and analysis of undersurface structures withhigh resolution and performance [2].Modern methods of electron microscopy based on ion beam (FIB-SEM) sample preparation provide a high quality of the cross-sectional surface and accurateinformation about the subsurface structure, however, FIB-SEM does not provide access to deep buried structures and high speed of sample preparation, what is required by the modern electronics industry. A unique solution for cross-sectional access to deeply buried structures is the integration of a laser beam into the FIB-SEM (laser FIB), which provides fast removal of large volumes of material with high speed. Laser FIB provides all advantages of integrates a fs-laser for speed, a Ga+ beam for accuracy, and a SEM for high resolution imaging to enable the fastest workflows. The isolated laser chamber prevents contamination of the electron column and detectors, while ensuring sample integrity with automated transfer between the SEM and laser chamberunder vacuum. Integration of the laser and FIB into a single system, automation of process parameters and laser shuttling and correlative workflows provide the fastest results and highest success rates. Fs-laser ablation is a thermal so the laser affected zone is minimal, and it is often possible to image cross sectional structure immediately after laser ablation, without FIB polishing [1].The latest developments, implemented in the laser-integrated FIB-SEM, such as an automated shuttle, NavCam integration, preset recipes, and the Cross-jet option for cover glass protection, improve the cross-sectioning process and ensure the automation, repeatability, and efficiency of the sample preparation. The combination of batch mode and other parameters of the laser milling process improves the high ablation rate and surface quality, which is especially effective for wide-gap semiconductor cross-sections. A combination of 3D X-ray microscopy (XRM) techniques and integrated laser scanning electron microscopes with a focused ion beam for sample preparation provides a workflow to improve precise targeting for specific analysis of buriedfeatures and correlation with additional equipment to provide subsurface analysis [3]. We describe a workflow using 3D XRM and Laser FIB for precise targeting and high throughput results and demonstrate the application examples. Correlated workflows accelerate results by connecting tools to quickly navigate between multiple length scales and imaging modes.[1] B.Tordoff, C. Hartfield, A. Holwell, S.Hiller, M. Kaestner, S. Kelly, J. Lee, S. Müller, F. Perez-Willard, T.Volkenandt, R. White, T. Rodgers; The LaserFIB: new application opportunities combining a highperformance FIB-SEM with femtosecond laser processing in an integrated second chamber; AppliedMicroscopy 50 (2020), 24.[2] C.Hartfield, W.Harris, A. Gu, M.Terada, V.Viswanathan, L. Jiao and T. Rodgers; Emerging Technologiesfor Advanced 3D Package Characterization to Enable the More-Than-Moore Era; ECS Transactions 109(2022), 15.[3] A. Gu, M. Terada, H. Stegmann, T. Rodgers, C. Fu, Y. Yang; From System to Package to Interconnect:An Artificial Intelligence Powered 3D X-ray Imaging Solution for Semiconductor Package StructuralAnalysis and Correlative Microscopic Failure Analysis; 2022 IEEE International Symposium on thePhysical and Failure Analysis of Integrated Circuits (IPFA) (2022)

Wear Reduction in Heavily Loaded Units of Transport Vehicles

Introduction. The pivot assembly provides connection between the rotating and non-rotating parts of machines and mechanisms such as cranes, excavators, trailers, railway rolling stocks. In relation to rolling stock, it connects the load-carrying part of the car with the bogie and is one of the most critical and wear-out friction units. Its technical condition affects the intensity and form of wear of the surfaces themselves, the amount of resistance to rotation of the bogie when the car moves in curved sections of the track, the amplitude of the lateral rocking of the car, the intensity of wear of the wheel flanges and, as a consequence, the safety of operation of the rolling stock as a whole. Until now, periodic grease is used for this unit, which, even with a short mileage, manages to be squeezed out of the contact zones and, thereby, creates conditions for the predominance of dry friction. Until now, various proposals to solve this problem have not found application in mass production for a number of reasons, and therefore the search for ways to reduce wear in the pivot assembly of cars is still relevant. This study proposes a solution to this problem that does not require structural changes to the pivot assembly itself. The aim of this work was to develop a technologically advanced anti-friction coating with good adhesion, which will be applied to the surface of a replaceable disk installed between the rubbing surfaces of the pivot assembly during scheduled repairs of the car chassis. This approach will reduce the friction force and wear rate in the unit when lubrication shortage occurs due to squeezing out of the grease. Materials and Methods. Antifriction characteristics of the developed coating was observed on a friction machine providing specific loads on the test sample up to 5000 N and a sliding speed from 0.13 m/s. The samples were examined by scanning electron microscopy (FEI Quanta 200 microscope). SEM images were acquired in a back-scattered electron (BSE) mode using a semiconductor detector. To analyze the elemental composition of beam samples, an energy dispersive spectrometer (EDAX Element EDS system) was used. Results. A three-layer functional phosphorus-containing composite coating of the surfaces of the unit was developed, which made it possible to significantly reduce the coefficient of friction and, as a consequence, the intensity of wear of the pivot unit surface during dry friction. The optimal conditions for obtaining composite coating layers were determined. The influence of the thickness of each layer and the conditions for its production on its functional characteristics was studied. Discussion and Conclusion. The proposed solution is manufacturable and, with appropriate adaptation, can be used to reduce wear in any open pivot assembly without radically changing its design. The methods for producing coating layers are accessible and technologically advanced for serial use.

Interaction Strength of Hanger and Horizontal Steel Reinforcement of Dapped End Beams

The dapped end beam members have a special end with low depth at the support area, which results in a weak area against shear stresses. Classical structural analysis doesn’t capture the precise steel reinforcement interaction at the dapped zone area. The main objectives of this study are to investigate the strength of the dapped end area and to analyze stresses in the steel reinforcement to evaluate the shear failure mechanism at the re-entrant corner. The experimental tests conducted on RC beam samples, in addition to the numerical simulation of these samples by a finite element program, have been compared with a mathematical model. The experimental program highlighted the strains in the steel reinforcement in the dapped region to calculate the magnitude of the stresses in the steel reinforcement. In the experimental program, six dapped beams were fabricated with a length of 3 m, a width of 150 mm, and a depth of 300 mm. The notched end has a 150-mm depth and 150-mm height. These beams were loaded by a concentrated load near support to investigate the shear strength capacity. From the results for steel reinforcement strain, it is found that hanger and horizontal steel reinforcements interact to provide dapped end shear strength. The study proposes a new approach to computing shear strength capacity at the re-entrant corner by adding the contributions of the horizontal and hanger steel reinforcement using an appropriate proportion strain factor. This method revealed greater carrying capacity for the dapped end beam compared with other common structural methods. The results of the numerical analysis were done by the ABAQUS finite element program, showing the same behavior as the experimental work. This study proved the common contribution of hanger and horizontal re-entrant corner steel reinforcement and proposed a new formula to determine the updated nominal shear strength. Doi: 10.28991/CEJ-2023-09-12-015 Full Text: PDF

Increasing the Strength of Fine-Grained Concrete with the Use of Carbon Nanotubes and Mechanical Activation of the Mixture

The results of studies to determine the effect of introducing a complex additive of carbon nanotubes and plasticizer into the composition of fine-grained concrete are presented. Two series of tests of beam samples were performed, and the strength characteristics of the studied compositions were determined. Two methods of introducing nano-additives into concretes were compared: using an ultrasonic dispersant and a linear induction wave action apparatus (LIA) by analyzing two series of tests of different compositions. It was established that the introduction of nanotubes using LIA provides a minimally greater increase in the compressive strength due to the activation of the cement binder by means of regrinding. However, the maximum increase in strength is achieved equally for each of the injection methods.

Operando two-terminal devices inside a transmission electron microscope

Advanced nanomaterials are at the core of innovation for the microelectronics industry. Designing, characterizing, and testing two-terminal devices, such as metal-insulator-metal structures, is key to improving material stack design and integration. Electrical biasing within in situ transmission electron microscopy using MEMS-based platforms is a promising technique for nano-characterization under operando conditions. However, conventional focused ion beam sample preparation can introduce parasitic current paths, limiting device performance and leading to overestimated electrical responses. Here we demonstrate connectivity of TEM lamella devices obtained from a novel electrical contacting method based solely on van der Waals forces. This method reduces parasitic leakage currents by at least five orders of magnitude relative to reported preparation approaches. Our methodology enables operation of stack devices inside a microscope with device currents as low as 10 pA. We apply this approach to observe in situ biasing-induced defect formation, providing valuable insights into the behavior of an SrTiO3-based memristor.

Feasibility of Green Concrete as a Material of Precast Beams for Residential House

The development of the residential house construction industry requires the discovery of cheap materials and the production of effective work systems. This study focuses on finding feasible measures and maintenance methods in the pre-painted beam industry that are cheap and suitable for simple homes. Researchers made three types of reinforced concrete beam samples, totaling 60 samples. Reinforced concrete beams are made from green concrete made from rice husk ash as a partial replacement for cement. The types of treatment applied in making samples are air curing and hessian. The results of this research show that the effective bending strength of the beam is found at a size of 15 x 20 x 60 cm. while the type of treatment that is good and easy to apply is hessian.

Contribution of Plastic Waste in Recycles Concrete Aggregate Paving Block

Road pavements generally use asphalt and cement concrete as flexible and rigid pavements. A flexible pavement covering material with concrete paving blocks has been developed for low-traffic road structures. Paving block compressive strength tests still use beam samples; some have used cube samples. Concrete waste and plastic waste can reduce material requirements and support environmental sustainability. Therefore, it is used as a recycled material. This research utilizes concrete waste and plastic waste in the composition of the concrete paving block mixture. Compressive and flexural strength tests with a cement and aggregate ratio 1:3 was used in this study. The aggregate comprises screening, sand, stone ash, recycled concrete aggregate, and plastic waste additives. The test results showed that the concrete paving block test objects in the form of cubes and beams produced different characteristics. Cube-shaped concrete paving blocks make more realistic compressive strength test values. Judging from the results of the compressive strength and flexural strength tests, the addition of plastic decreased the strength of the concrete paving block. Still, the addition of 4-6% plastic waste positively contributed to the value of flexural strength.

Correction and integration of solid-angle data from the azimuthally resolving 2D detector at ID06-LVP, ESRF.

The unique diffraction geometry of ESRF beamline ID06-LVP offers continuous static 2D or azimuthally resolving data collections over all accessible solid angles available to the tooling geometry. The system is built around a rotating custom-built Pilatus3 CdTe 900k-W detector from Dectris, in a configuration equivalent to three butted 300k devices. As a non-standard geometry, here the method of alignment, correction and subsequent integration for any data collected over all solid angles accessible, or over any azimuthal range contained therein, are provided and illustrated by parameterizing and extending existing pyFAI routines. At 1° integrated intervals, and typical distances (2.0 m), the system covers an area of near 2.5 m2 (100 Mpx square equivalent), to 0.65 Å resolution, at 53 keV from a total dataset of some 312 Mpx. Standard FWHMs of SRM660a LaB6 vary from 0.005° to 0.01°, depending on beam size, energy and sample dimensions, and are sampled at an elevated rate. The azimuthal range per static frame ranges from <20° to ∼1° over the full range of the detector surface. A full 2θ-intensity data collection at static azimuth takes 1-3 s typically, and can be reduced to ms-1 rates for measurements requiring time-rate determination. A full solid-angle collection can be completed in a minute. Sample detector distances are accessible from 1.6 m to 4.0 m.

Laser-based vibration measurement using diffractive beam samplers for vibration monitoring of large-scale bridges

This paper introduces an innovative design for a laser-based apparatus employing diffractive beam sampling technology, with the primary purpose of characterizing vibration frequencies induced within large-scale bridges. The functioning principle of the device hinges upon its ability to discern minute alterations in the relative positions of a subset of the laser beam, resulting from the oscillatory behavior of a laser pendulum mechanism. The captured dynamic variations are seamlessly integrated into a real-time monitoring framework through the utilization of an adept image sensor, complemented by sophisticated software functionalities. Noteworthy for its amalgamation of straightforward implementation and remarkable precision, the proposed methodology stands as a potent instrument poised to ensure the secure and robust surveillance of the structural well-being of large-scale bridges.

Experimental and numerical investigations of masonry ‎ beams performance under bending loads

An experimental and numerical study was achieved to investigate the behavior of masonry beams internally reinforced using carbon fiber-reinforced polymer (CFRP) and hybrid steel/CFRP reinforcements. In addition, the use of masonry equivalent material characteristics in the numerical modeling instead of modeling the blocks and mortar was evaluated. Three beams were built using cement bricks and tested in three-point bending with an effective simply supported span of 840 mm. The bricks were designed with a hole that was filled with grout before placing the rebar inside. Material characterization tests were performed to evaluate the mechanical properties of the brick, mortar, and masonry blocks. The beam samples were tested under static loads and the load deformation and failure load were monitored. Finite element methods were built for the beams and validated using the experimental results. The model was used to study more parameters such as the distance between the stirrups and the hybrid reinforcement configuration. Results showed that hybrid reinforcement is the best reinforcement configuration. It can be concluded that the reinforced masonry systems were able to achieve flexural resistance with maximum resistance when using the hybrid reinforcement.