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This paper aims to present the methodology and results of the experimental characterization of three-dimensional (3D) printed acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) parts utilizing digital image correlation (DIC).

Tensile and shear characterizations of ABS and PC 3D-printed parts were performed to determine the extent of anisotropy present in 3D-printed materials. Specimens were printed with varying raster ([+45/−45], [+30/−60], [+15/−75] and [0/90]) and build orientations (flat, on-edge and up-right) to determine the directional properties of the materials. Tensile and Iosipescu shear specimens were printed and loaded in a universal testing machine utilizing two-dimensional (2D) DIC to measure strain. The Poisson’s ratio, Young’s modulus, offset yield strength, tensile strength at yield, elongation at break, tensile stress at break and strain energy density were gathered for each tensile orientation combination. Shear modulus, offset yield strength and shear strength at yield values were collected for each shear combination.

Results indicated that raster and build orientations had negligible effects on the Young’s modulus or Poisson’s ratio in ABS tensile specimens. Shear modulus and shear offset yield strength varied by up to 33 per cent in ABS specimens, signifying that tensile properties are not indicative of shear properties. Raster orientation in the flat build samples reveals anisotropic behavior in PC specimens as the moduli and strengths varied by up to 20 per cent. Similar variations were observed in shear for PC. Changing the build orientation of PC specimens appeared to reveal a similar magnitude of variation in material properties.

This article tests tensile and shear specimens utilizing DIC, which has not been employed previously with 3D-printed specimens. The extensive shear testing conducted in this paper has not been previously attempted, and the results indicate the need for shear testing to understand the 3D-printed material behavior fully.

This research is part of a project that aims to investigate using foamed concrete structurally in houses. Foamed concrete has a porous structure that makes it light in weight, good in thermal insulation, good in sound insulation and workable.

An experimental program is conducted in this research to investigate the behavior of polypropylene fiber reinforced foam concrete beams laterally reinforced with/without glass fiber grid.

The results proved the effectiveness and efficiency of using glass fiber grid as lateral reinforcements on the shear strength of reinforced foam concrete ribs, in reducing the cracks width and increasing its shear capacity, contrary to using glass fiber grid of reinforced foam concrete beams since glass fiber grid did not play good role in beams.

Limited literature is available regarding the structural use of foam concrete. However, work has been done in many countries concerning its use as insulation material, while limited work was done on structural type of foam concrete.

The sheathing panels of traditional light wood frame shear walls mainly use oriented strand board (OSB) panels, and the damage of the traditional walls is mainly caused by the tear failure at the bottom corner of the OSB panel. In order to improve the lateral performance of the traditional light wood frame shear wall, a new type of end narrow panels reinforced light wood frame shear wall is proposed.

The monotonic loading tests and finite element analysis of nine groups of walls, with different types of end narrow panel, types of fasteners used on the end narrow panels and the end narrow panels edge fastener spacing, are carried out. The effects of different characters on lateral performance of light wood frame shear walls are reported and discussed.

The failure modes of the wall reinforced by parallel strand bamboo narrow panels with 150 mm edge nails spacing are similar to the traditional wall. Conversely, the failure modes of other groups of walls reinforced by end narrow panels are the tears of the bottom narrow panel or the bottom beam. The end narrow panel reinforced light wood frame shear wall can make full use of the material property of sheathing panels. Compared with the lateral performance of traditional walls, the new-type end narrow panels reinforced walls have better lateral performance.

A new type of end narrow panels reinforced light wood frame shear wall is proposed, which can enhance the lateral performance of the traditional light wood frame shear wall. The new-type walls have advantages of convenient operation, manufacture cost saving and important value of engineering application.

The study aims to display the bubbles' evolution in the shear layer and their relationship with the pressure fluctuations. Furthermore, the coherent structures of the first six modes are extracted, in order to provide insight into their temporal and spatial evolution and determine the relationship between cavitating bubbles and coherent structures.

In the present study, numerical simulations of submerged jet cavitating flow were carried out at a cavitation inception condition inside an axisymmetric cavity using the large eddy simulation (LES) turbulence model and the Schnerr–Sauer (S–S) cavitation model. Based on snapshots produced by the numerical simulation, dynamic mode decomposition (DMD) was performed to extract the three-dimensional coherent structures of the first six modes in the shear layer.

The cavitating bubbles in the shear layer are deformed to elongated ellipsoid shapes by shear forces. The significant pressure fluctuations are induced by the collapse of the biggest bubble in the group. The first mode illustrates the mean characteristics of the flow field. The flow in the peripheral region of the shear layer is mainly dominated by large-scale coherent structures revealed by the second and third modes, while different small-scale coherent structures are contained in the central region. The cavitating bubbles are associated with small size coherent structures as the sixth or higher modes.

This work demonstrates the feasibility of LES for high Reynolds number shear layer flow. The dynamic mode decomposition method is a novel method to extract coherent structures and obtain their dynamic information that will help us to optimize and control the flow.

(1) This paper first displays the three-dimensional coherent structures and their characteristics in the shear layer of confined jet flow. (2) The relationship of bubbles shape and pressure fluctuations is illustrated. (3) The visualization of coherent structures benefits the understanding of the mixing process and cavitation inception in jet shear layers.

The purpose of this study is to improve the lateral capacity of Cold-Formed Steel (CFS) frame walls filled with lightweight foamed concrete (LFC) and supported with straw boards by introducing structural foamed concrete and/or bracing.

Finite element models are developed and calibrated based on previous experimental work. Then, these models are extended to conduct a parametric study to quantify the effect of filling CFS walls and structural LFC and the effect of supporting CFS walls with bracing.

Results of the study conclude that the finite element analysis can be used to simulate and analyze the lateral capacity of CFS walls effectively since the maximum deviation between calibrated and experimental results is 10%. The structural LFC usage in CFS walls improves the lateral capacity considerably by (25–75) % depending on the wall properties. Besides, the application of lateral bracing does not always have a positive effect on the lateral performance of these walls.

Although CFS walls are preferred due to it is light in weight, low in cost, easy to install and recyclable, low seismic performance, buckling vulnerability, poor thermal insulation and sound insulation properties, low lateral stiffness, and low shear strength limit their use. This study proposes the use of structural foamed concrete and a different bracing method than what is available in the literature. This can overcome the drawbacks of the CFS walls alone which can permit the usage of such walls in mid-rise buildings and other applications.

Sandwich construction has developed and has become an integral part of lightweight construction. In the recent projects, it has been shown that by using sandwich panels as stabilizing members, a considerable amount of savings of steel can be achieved for structural members at ambient temperature. These stabilizing effects may also help to achieve similar savings in case of fire.

The response of a sandwich single panel as well as the behaviour of the whole structure at ambient temperature and in case of fire is influenced by joints between the sandwich panels and the sub-structure. The fastenings used to fix the sandwich panels to a sub-structure may be loaded by shear forces caused by self-weight, live loads or diaphragm action. Therefore, an experimental investigation was conducted to investigate the shear behaviour of sandwich panel joints in fire.

This paper summarized briefly the experimental results, numerical simulations and analytical models on the shear behaviour of sandwich panel joints at ambient and elevated temperatures.

The work is limited to studied types of screws and sandwich panels which are generally used in current sandwich construction.

These stabilizing effects in sandwich construction help to achieve savings in case of fire.

Sandwich construction has developed and has become an integral part of lightweight construction. In the recent projects, it has been shown that by using sandwich panels as stabilizing members, a considerable amount of savings of steel can be achieved for structural members at ambient temperature. These stabilizing effects help to achieve similar savings in case of fire.

This paper summarized briefly the experimental results, numerical simulations and analytical models on the shear behaviour of sandwich panel joints at ambient and elevated temperatures, which were not published yet.

Recycled concrete is an economical and environmentally friendly green material. The shear performance of recycled concrete load-bearing masonry is studied, which is great of significance for its promotion and application and also has great significance for the sustainable development of energy materials.

In total, 30 new load-bearing block masonry samples of self-insulating recycled concrete are subjected to pure shear tests, and 42 samples are tested subjected to shear-compression composite shear tests. According to the axial design compression ratio, the test is separated into seven working conditions (0.1–0.8).

According to the test results, the recommended formula for the average shear strength along the joint section of recycled concrete block masonry is given, which can be used as a reference for engineering design. The measured shear-compression correlation curves of recycled concrete block masonry are drawn, and the proposed limits of three shear-compression failure characteristics are given. The recommended formula for the average shear strength of masonry under the theory of shear-friction with variable friction coefficient is given, providing a valuable reference for the formulation of relevant specifications and practical engineering design.

Simulated elastoplastic analysis and finite element modeling on the specimens are performed to verify the test results.

This paper aims to investigate the effect of shear rate, concentration (4–20 kg/m³) and temperature (20°C–60 °C) on the apparent viscosity of apricot gum solutions.

Apparent viscosity has been measured using a rotational viscometer.

It has been observed that the shear stress and apparent viscosity values increase at high concentrations in the prepared apricot gum solutions. However, it is understood that the higher the temperature in the operation conditions, the lower the apparent viscosity results. Power-law is found the best-fitting model to illustrate the changes in temperature and concentration. According to the consistency coefficient and flow behavior indices, the apricot gum displayed shear-thinning behavior (pseudoplastic). The apricot gum is a polysaccharide with amino and uronic acids, according to Fouirer Transform Infrared Spektrofotometre spectra.

The results suggest that power-law model can be used to estimate the viscosity of apricot gum solutions at different temperatures and concentrations for applications for which flow behavior should be taken into account.

Exudate gums have good rheological properties and, therefore, are widely used in the food industry. Apricot gum is a biodegradable and abundant polysaccharide that enhances viscosity, stabilizes suspension or emulsion and improves the flow properties of foods. Different rheological models are used to investigate rheological properties. However, those models are time-independent to fit the experimental data.

The objective of this paper is to quantitatively assess shear band evolution by using two-dimensional discrete element method (DEM).

The DEM model was first calibrated by retrospectively modelling existing triaxial tests. A series of DEM analyses was then conducted with the focus on the particle rotation during loading. An approach based on particle rotation was developed to precisely identify the shear band region from the surrounding. In this approach, a threshold rotation angle ω₀ was defined to distinguish the potential particles inside and outside the shear band and an index g(ω₀) was introduced to assess the discrepancy between the rotation response inside and outside shear band. The most distinct shear band region can be determined by the ω₀ corresponding to the peak g(ω₀). By using the proposed approach, the shear band development of two computational cases with different typical localised failure patterns were successfully examined by quantitatively measuring the inclination angle and thickness of shear band, as well as the microscopic quantities.

The results show that the shear band formation is stress-dependent, transiting from conjugated double shear bands to single shear band with confining stress increasing. The shear band evolution of two typical localised failure modes exhibits opposite trends with increasing strain level, both in inclination angle and thickness. Shear band featured a larger volumetric dilatancy and a lower coordination number than the surrounding. The shear band also significantly disturbs the induced anisotropy of soil.

This paper proposed an approach to quantitatively assess shear band evolution based on the result of two-dimensional DEM modelling.

From the factors that affect shear strength of reinforced concrete (RC) beams, the study examines the effect of controversial parameters, width-to-depth (b/d) and effective length-to-depth (l_eff/d) ratio on shear strength of RC slender beams.

The researchers utilized a database of 676 experimental test results from ACI-DAfStb database, Conducted regression analysis to examine relationship between b/d and l_eff/d ratios and shear strength, compare and analyze sensitivity to changes in b/d and l_eff/d ratios for the selected 12 shear models for RC beams.

Increasing b/d ratio enhanced shear strength until b/d ˜ 3, but further increases had limited impact and increasing l_eff/d ratio resulted in decreased shear strength. From comparative analysis, the models provided by various design standards were found to be safe, with EC-2 and JSCE models being conservative. From considered research models, Campione and Arslan models were conservative, while Kim and White model were observed to be unsafe. Sensitivity analysis indicated ACI318-19, JSCE, CEB-FIP-90 and Arslan models were sensitive to changes in b/d and l_eff/d ratios. National code models generally captured shear strength characteristics well. Certain models suggested a constant/decreasing b/d effect despite observed shear strength enhancement. Most models indicated improved shear strength with an increasing l_eff/d ratio, contrary to experimental findings while TS500 and Hwang models aligned with experimental results.

The study's limitations include the dependence on the available database, which may not encompass all possible experimental scenarios. Further research should aim to expand the database and investigate additional parameters that may influence shear strength in RC beams.

The findings of this study have practical implications for the design and analysis of RC beams by suggesting that the width-to-depth and length-to-depth ratios should be carefully considered to optimize shear strength. The identified models can assist engineers in selecting appropriate shear strength prediction models based on specific design scenarios.

The study contributes to the advancement of knowledge in the field of reinforced concrete beam design, which has implications for the safety and reliability of structural systems. By understanding the factors influencing shear strength, engineers can design more efficient and robust structures, ensuring the safety of buildings and infrastructure.

This study provides valuable insights into the influence of the width-to-depth and effective length-to-depth ratios on shear strength in reinforced concrete beams. It contributes to the understanding of these factors and their impact on shear strength, addressing the lack of consensus among researchers. The comparative analysis of shear models and the sensitivity analyses add value by identifying the models that align better with experimental observations. The study emphasizes the need for accurate models that account for these factors and highlights the importance of further research to refine and develop improved predictive models.