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This research aims to determine the influence of water-soaking on polyester-based coated woven fabrics for ultimate tensile strength and elongation at break under uniaxial tensile tests. The paper begins with a short survey of literature concerning the investigation of the determination of coated woven fabric properties. The authors carried out the uniaxial tensile tests with an application of a flat grip to establish the values of the ultimate tensile strength of groups of specimens treated with different moisture conditions. SEM fractography is performed to determine the cross-section structures of coated woven fabrics. The change in the mechanical properties caused by the influence of water immersion has not been noticed in the performed investigations. [ABSTRACT FROM AUTHOR]

The main aims of the current research were: (1) to analyze in detail the tensile modulus and ultimate tensile strength (UTS) of orbital wall bones separately for the left and right orbit of the same cadaver and (2) to compare the obtained results with a flexural modulus of the left and right orbit reported earlier by A. C. van Leeuwen et al. [14]. A set of 54 specimens of orbital superior and/or medial walls harvested from 16 human skulls (4 female, 12 male) were tensioned at 0.01 mm/s till fracture. The samples were taken always from both orbits of the same cadaver. For each sample, cross-section area, apparent density, tensile modulus, and UTS were identified. For pooled female and male group apparent density for right and left orbit was identified to be 1.59 ± 0.52 SD) g/cm³ and 1.51 ±0.48 SD) g/cm³, tensile modulus of 2028 ±1729 SD) MPa and of 2706 ±2812 SD) MPa, and UTS of 14.17 ±15.00 SD) MPa and of 15.03 ±11.44 SD) MPa, respectively. For tensile tests, there were no statistical differences between the left and right orbit for pooled male and female groups for (a) apparent density (Student's t-test p = 0.567), (b) UTS (Mann-Whitney U-test p = 0.350) and (c) tensile modulus (Mann-Whitney U-test p = 0.716). For bending tests, there were no statistical differences between the left and right orbit for the pooled male and female group for (a) orbital wall thickness (Student's t-test p = 0.811) and (b) flexural modulus (Mann-Whitney U-test p = 0.206). The comparative analysis between tensile and flexural moduli for pooled left and right groups (with no distinction for male and female) revealed no statistically significant difference (Mann-Whitney U-test p = 0.074). The maximum tensile modulus was 7279 MPa and 9913 MPa for the right and left orbit, respectively, and was similar to the maximum flexural modulus of 6870 MPa and 9170 MPa reported in an earlier study, for the right and left orbit, respectively. [ABSTRACT FROM AUTHOR]

This research aims to determine the influence of the cyclic process of freezing and defrosting on the mechanical properties of the chosen glass fibres and PTFE-coated woven fabrics. The specimens were subjected to freezing at about -20°C for 4 h and thawing by full immersion into the water at about ,20°C for 4 h. The fabric samples after 25 and 50 frozen cycles were air-dried at room temperature for one week and then subjected to uniaxial tensile tests. The same tests have been performed on a reference group of specimens, which were not exposed to temperature change. The authors determined the tensile strength, and longitudinal stiffnesses resulting from performed tests. Although the investigated coated woven fabrics expressed a reduction in the tensile strength in water soaking conditions, the performed frozen cycles don't show a significant decrease in strength under uniaxial tensile tests. [ABSTRACT FROM AUTHOR]

This paper describes the current condition of some dovetail joints which form the wall corners of two Greek Catholic churches of wooden construction in Polish Subcarpathia. It also gives the historical background of the sacral architecture of that region. The two structures, which represent the same type of log corner joints are situated in Chotylub and Cewków. The buildings were examined e.g. for damage, wood moisture content, out-of-plane deviations and changes in the geometry of the walls. The study is based on in-situ examination and structural analysis of the joints. Finite element simulations of the statics of joints built of old, and mixture of old and new, wood are performed in order to show how the change of material properties affects their structural behaviour. Also, a sensitivity analysis is performed to describe the effect on potential repairs that combining old damp wood with new and dry joint members might have. [ABSTRACT FROM AUTHOR]

The purpose of the paper is the estimation of the polyvinyl chloride – polyester-coated fabric (Precontraint 1202 S2) mechanical properties under uniaxial tensile tests as well as short- and long-time creep tests. The uniaxial tests are the basis of non-linear elastic description while the creep tests are used for the evaluation of the stiffness parameters in time and for the identification of the standard viscoelastic model. The paper also includes a short survey of literature concerning the coated woven fabric description. [ABSTRACT FROM AUTHOR]

This paper describes the method of laboratory tests necessary for identification of temperature influence on mechanical properties of polyvinylidene fluoride-coated polyester fabric often used for tensile structures. Two nonlinear model descriptions are investigated. The first one is based on the piece-wise linear relations between stress and strain and the second one on the Murnaghan model of solid behavior. This paper is proposed as an introduction to the comprehensive investigation on thermal changes of material properties of coated woven fabrics. [ABSTRACT FROM PUBLISHER]

The aim of the present paper is to propose a method of laboratory tests necessary for the identification of mechanical properties of the coated fabric. The material parameters of the coated fabric AF 9032 are specified on the basis of the uniaxial and biaxial tensile tests. For the identification process, the techniques based on the least squares methods are used. Additionally, the uniaxial and biaxial cyclic tests are performed in order to observe a change of immediate mechanical properties under cyclic load. [ABSTRACT FROM AUTHOR]

The impact of water-induced degradation on the mechanical properties of the chosen two PTFE-coated, glass threads woven fabrics is investigated in this paper. The paper begins with a survey of literature concerning the investigation and determination of coated woven fabric properties. The authors carried out the uniaxial tensile tests with an application of flat and curved grips to establish the proper values of the ultimate tensile strength and the longitudinal stiffness of groups of specimens treated with different moisture conditions. Despite the water resistance of the main materials used for fabrics manufacturing, the change of the mechanical properties caused by the influence of water immersion has been noticed. The reduction in the tensile strength resulting under waterlogged is observed in the range from 5% to 16% depending on the type of investigated coated woven fabric and direction of weft or warp. [ABSTRACT FROM AUTHOR]