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The purpose of this paper is to investigate the effect of laundering on the drape, shear, and bending properties of bottom weight fabrics.

Six bottom‐weight 100 percent cotton fabrics were included. Collier's Drape Tester was utilized to obtain drape values. Bending and shear values were measured on the KES‐F Shear Tester and the Pure Bending Tester. Three laundering cycles (unlaundered, one and five home launderings) following AATCC methods were explored.

Laundry cycle did not have a significant effect on fabric drape, shear or bending properties. However, drape values increased overall, while shear and bending modulus and hysteresis decreased, resulting in a more drapable, pliable fabric after five laundry cycles.

Future research examining a wider variety of fabrics and conducting a greater number of laundry cycles to approximate an average yearly number of laundry cycles is recommended. An expansion of this preliminary study should give more conclusive evidence of the trends observed.

Objective measurement of drape and fabric mechanical properties related to drape after laundry treatments would assist the apparel manufacturer in developing laundry recommendations based on the fabric's performance and in selecting fabrics which maintain their drape characteristics, mechanical properties, and dimensional stability with use. Higher quality garments with increased consumer satisfaction would result.

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.

The purpose of this paper is to study the effect of the addition of silicon carbide (SiC) microparticles and their contributions regarding the tensile and shear properties of the T800 fiber reinforced polymer composite at various fiber volume fractions. The tensile and shear properties of the hybrid composites where continuous T800 fibers are used as reinforcements in an epoxy matrix embedded with SiC microparticles have been studied.

The results were obtained by implementing a micromechanics approach assuming a uniform distribution of reinforcements and considering one unit cell from the whole array. Using the two-step homogenization process, the properties of the materials were determined by using the finite element analysis (FEA). The predicted elastic properties from FEA were compared with the analytical results. The analytical models were implemented in the MATLAB Software. The FEA was performed in ANSYS APDL.

The mechanical properties of the hybrid composite had increased when compared with the properties of the conventional FRP. The results suggest that SiC particles are a good reinforcement for enhancing the transverse and shear properties of the considered fiber reinforced epoxy composite. The microparticle embedment has significant effect on the transverse tensile properties as well as in-plane and out-of-plane shear properties.

This is significant because improving the properties of the composite materials using different methods is of high interest in the materials community. Using this study people can work on the process of including different type of microparticles in to their composite designs and improve their performance characteristics. The major influence of the particles can be seen only at lower volume fractions of the fiber in the composite. Only FEA and analytical methods were used for the study.

Material property improvements lead to more advanced designs for aerospace and defense structures, which allow for high performance under unpredictable conditions.

This type of study proves that the embedment of different microparticles is a method that can be used for improving the properties of the composite materials. The improvement of the transverse and shear properties will be useful especially in the design of shell structures in the different engineering applications.

This study aims on a broad review of Concrete's Rheological Properties. The Concrete is a commonly used engineering material because of its exquisite mechanical interpretation, but the addition of constituent amounts has significant effects on the concrete’s fresh properties. The workability of the concrete mixture is a short-term property, but it is anticipated to affect the concrete’s long-term property.

In this review, the concrete and workability definition; concrete’s rheology models like Bingham model, thixotropy model, H-B model and modified Bingham model; obtained rheological parameters of concrete; the effect of constituent’s rheological properties, which includes cement and aggregates; and the concrete’s rheological properties such as consistency, mobility, compatibility, workability and stability were studied in detail.

Also, this review study has detailed the constituents and concrete’s rheological properties effects. Moreover, it exhibits the relationship between yield stress and plastic viscosity in concrete’s rheological behavior. Hence, several methods have been reviewed, and performance has been noted. In that, the abrasion resistance concrete has attained the maximum compressive strength of 73.6 Mpa; the thixotropy approach has gained the lowest plastic viscosity at 22 Pa.s; and the model coaxial cylinder has recorded the lowest stress rate at 8 Pa.

This paper especially describes the possible strategies to constrain improper prediction of concrete’s rheological properties that make the workability and rheological behavior prediction simpler and more accurate. From this, future guidelines can afford for prediction of concrete rheological behavior by implementing novel enhancing numerical techniques and exploring the finest process to evaluate the workability.

Some of the basic mechanical characteristics such as tensile, bending, shear, compression, and surface properties of cotton knitted fabrics after a durable flame‐retardant finishing, were studied by the objective‐evaluation method developed by Kawabata and Niva using the KES‐F system. In addition, properties such as bursting strength, drape and sewability were studied in order to further explore the influence of this treatment on the fabrics. All treated fabrics were flame‐retardant but their mechanical properties showed changes as a result of the above finishing. More specifically, a significant reduction in the bending and shear properties was recorded, which suggests that the flame‐retardant finishing primarily affects the above characteristics.

In transforming fabrics into garment it is necessary to know, besides the manner of processing, the behaviour of the fabric in particular manufacturing processes. It is necessary to define why and how fabrics behave in a particular way when exposed to various strains. The answers to these questions are obtained by investigating fabric mechanics, as non‐linear mechanical fabric properties at lower strains, which is the case in transforming fabrics into garments. The area to be investigated is quite wide and the investigations presented here deal only with the most important elastic strains occurring in processing fabrics into garments, such as tensile, pressure, shear and bending, as each individual type of strain bears specific importance in studying fabric behaviour, as well as in garment quality control. Strains impacting the fabric, i.e. the reaction of the fabric to these strains, are presented through the parameters of mechanical properties. A relation is also explained between characteristic histeresis curves and fabric behaviour in real garment manufacturing processes, obtained through recording fabric behaviour in particular garment manufacturing processes. Results obtained through the investigations of mechanical properties of the fabrics analysed and their behaviour in garment manufacturing processes helped to determine the so‐called critical, or border values for particular parameters of mechanical properties.

The effects of failure mode and strain conditions of CFRP, concrete and stirrups on the shear capacity of reinforced beams bonded by geopolymer and epoxy are studied. In addition, a prediction model of the ultimate bearing capacity of CFRP-shear-strengthened beams is proposed, which considers adhesive performance parameters adhesive performance parameter ßE and FRP width parameter ßw.

This paper presents an experimental study on ultimate bearing capacity of CFRP-shear-strengthened pre-cracked beams with geopolymer and epoxy resin, which considers parameters such as impregnated adhesives types and CFRP-strengthened scheme.

The failure modes of CFRP-strengthened beams bonded by geopolymer are the combination of the CFRP-concrete interface substrate failure and fracture failure of CFRP, and that of epoxy is the local substrate failures with small area. The ultimate load of CFRP-strengthened beams is directly affected by the failure modes. The ultimate bearing capacity of CFRP-strengthened beams with geopolymer is 91.4% of that of epoxy resin. Compared with ultimate bearing capacity of CFRP-strengthened beams with U-shaped, that of complete-wrapping increases by 2.5%. Moreover, the stirrup peak strain is reduced by more than 30% in CFRP-strengthened beams bonded with geopolymer and epoxy resin in comparison with the unstrengthened beam. The existing prediction model cannot accurately predict the CFRP shear capacity contribution of strengthened beams with different CFRP-strengthened schemes and adhesive properties. The estimated results are much lower than the test data, and the deviation is much larger than 20%.

Geopolymer alternative to epoxy as an adhesive is feasible and effective for CFRP reinforcement. Furthermore, the accuracy is improved by introducing parameters about adhesive properties based on the existing prediction model. The estimated results are in excellent agreement with the test data, and the deviation is controlled within −12.80%, and the model is suitable for predicting the shear capacity of FRP-strengthened beams with ßf = 90° in shear capacity database.

For cloths having direct contact with the skin, comfort properties are a priority than the physical and mechanical properties. Innerwear clothes should induce pleasant feelings because they have a direct influence on human psychological satisfaction, health and work efficiency. The purpose of this study is to investigate the impact of cotton fiber parameters on the sensorial comfort of woven fabrics.

Four types of cotton fiber with different fineness, mean length, uniformity index, short fiber content, strength and elongation were used to develop yarns used to weave fabric samples. Kawabata evaluation system (KES) was used to analyze the fabrics’ sensorial comfort.

Results showed that cotton fiber parameters have a significant effect on surface friction and roughness properties. Low stress tensile, tensile resilience and tensile strain properties were affected by fiber micronaire, mean length, uniformity index, short fiber content, fiber strength and elongation. However, fabric shear, bending and compression properties were least dependent on fiber parameters. The correlation of the dependent variable and the independent variable was also statistically analyzed and reported. From the results, it was shown that cotton fiber parameters play a significant role in woven fabrics’ sensorial comfort.

The cloths that are in contact with the skin can be developed using the results of these studies to feel pleasant. This will, in turn, have a direct effect on the customer's psychological satisfaction, health and work performance.

The purpose of this paper is to present experimental research on the behaviour of a new electrorheological fluid (ETSERF).

The ETSERF is a suspension based on diatomite powders dispersed in silicon oil with a surfactant. A design of experiments is conducted to investigate the effects of electric field strength, particle concentration, surfactant percentage, particle size and shear rate on the efficiency of ETSERFs. The influence of the interactions on shear stresses is analyzed by varying all the combinations of the independent variables. The dielectric properties of the ETSERF are investigated in order to explain the interactions between these independent variables. Furthermore, a quantitative relationship between the dynamic shear stresses and the independent variables is developed.

The relationship provides a very useful explanation for the contributions of each independent variable to the viscosity and yield stress.

A new empirical model is proposed to explain the rheological behaviour of the ER fluids with a shear‐thinning behaviour.

Considering the “size effect” and the properties degradation of building materials on the strengthened engineering, in this paper, the technology of pasting steel plate was adopted to shear strengthen a 16 m prestressed concrete hollow slab, which had serviced 20 years in cold regions. The shear properties of shear strengthen beams are analyzed.

Shear loading test of the shear strengthened beam and the contrast beam was conducted. Then the mechanical characteristics, failure mechanism, the mechanical response and shear capacity of shear strengthened beam and contrast beam had been discussed.

The failure mode of shear strengthened beam and contrast beam was shear compression failure, and the bond failure between concrete and prestressed reinforcement happened in both of test beams. The shear strengthening method of pasting steel plate can effectively improve the mechanical response for the shear strengthened beam. Compared with the contrast beam, the cracking load and failure shear capacity for the shear strengthened beam can be effectively increased by 12.2 and 27.6%, respectively.

The research results can be a reference for the detection and evaluation of shear strengthened bridges, which are strengthened by pasting steel plate. Engineers can refer to the shear strengthening method in this paper to strengthen the existing bridge, which can guarantee the safety of shear strengthened bridges.