[en] The microplane model proves in this paper to be suitable also to the description of the multiaxial behavior of concrete, subjected either to tension or to compression, with or without shear. The microcracking, which is the most relevant caused of nonlinearity, is assumed to be localized in the thin mortar layers (cement paste and fine aggregates) which separate the coarse aggregate particles: these layers, called ''microplanes'' or ''weak planes'', are assumed to be present both at the microscopic and at the macroscopic level. Each microplane is characterized by a uniaxial constitutive relationship between the normal stress and the normal strain. The behavior of the concrete as a whole is adequately described (loading in compression, strain softening excluded; loading in tension, strain softening included; unloaded either from previous tension or from previous compression). Attention is focused on plane stress situations. Comparisons are made with many test data on the biaxial behavior of concrete. (orig./HP)

[en] The allowable structural stress properties of a straight pipe section are compared with the combined effect of accidental jetstream impact stresses and the stresses under operational conditions. The elastic stress analysis will be described. The assumptions applying to the full plastic stress analysis, and the required restrictions needed in order to deduce acceptable results, are discussed. (author)

[en] The concepts of fatigue strength analysis as the nominal stress concept, the local strain approach, the hot spot stress concept and the fracture mechanic concept are explained. As an example of welded structures a thick-walled pipe with butt weld is chosen. For the stress and strain analysis two-methods, the boundary element method (BEM) and the finite element method (FEM) were used. The mechanical model is defined, which was the basis of a strain analysis. Afterwords the results of the investigations (elastic and elastic-plastic conditions, yield curve, cyclic tension, torsion) are presented. (DG)

[en] The developments of measuring techniques, measuring methods and measuring instruments as well as their connection with computer technology are a challenge to experimental mechanics. The relevant knowledge and experiences are discussed in detail. 32 separate papers document the practical application of scientific fundamentals. Particular emphasis is placed on the reliability, the safe predetermination of structural loads, the quality and operational behaviour of structures. Nine papers have been abstracted separately. (DG)

[en] To determine the most accurate of cystourethrometric parameters in detecting urodynamic stress incontinence (USI ) in women. A case-control study was carried out in the Urodynamic Units in Aleppo University Hospitals, Aleppo, Syria, between January 2008 and June 2010. Seventy-six women suffering from either urgency, urge incontinence, stress incontinence, or mixed symptom, and attended to the urodynamic units were included in this study. Two groups were recruited, USI group (study group; n=52), who had the diagnosis of USI by the urodynamic study and non-USI group (control group; n=24), who did not have this diagnosis by urodynamic study. Comparison between the 2 groups in urodynamic findings was carried out. In the urodynamic study, maximal urethral closure pressure (MUCP) in the sitting position, transmission ratio (TR) in the sitting position, MUCP change (changing position from supine to sitting), and MUCP change% (percentage of maximal closure pressure change with position) were statistically lower in the USI group compared to control group. The most accurate parameters in detecting USI were MUCP change and MUCP change%, with a sensitivity of more than 90% and specificity of more than 70% at cut off values of Cystourethrometric parameters such as MUCP sitting, TR sitting, MUCP change, and MUCP change% measurement could be of value in distinguishing between USI women and non-USI women (Author).

[en] The 39 papers of the symposium present latest results and novel experience in the domain of stress analysis. For eight of the papers, a separate subject analysis has been made for the data base. (HP)

[en] The highest stresses in many thin walled piping systems are the local stresses at the pipe supports. These secondary stresses are caused by saddles or other structural discontinuities that restrain pipe ovalization. A static analysis of a thin walled pipe supported on structural steel saddle under dead weight loading is presented herein. The finite element analysis is performed using a shell model with distributed gravity and hydrostatic pressure loading. Parametric studies on global and local stress are performed to determine the effect of the pipe diameter to thickness ratio. Two aspects of the saddle design are also investigated: the effect of saddle width, and the effect of saddle wrap angle. Additionally, the computed stresses are compared to closed form solutions

[en] A method of separating the main tensions in the case of elements in plane state of stresses is presented. The method is based on determining the main stresses sum using the electrooptic analog. (orig.)

[en] Ultrasonic testing techniques yield information on residual stress conditions at the surface and in the body of a specimen or component. The testing principle uses the effects of elongation states on the propagation rate of ultrasonic waves. By combining two wave modes evaluation relations are obtained, with the travel times of ultrasonic waves being the only measured quantities in them. Computed analysis of stress in component parts relies on automated measurement of the ultrasonic wave travel time, as affected by elongation, and stress conditions are calculated by means of the material-specific elasticity constants. A universal measuring device has been built and tested that automatically measures the travel times and computes the absolute stress values, or stress differences, with recourse to evaluation relations stored in the memory which are defined for every specific testing task. (orig.)

[en] The guided wave propagation in inhomogeneous multi-layered structures is experimentally explored based on theoretical dispersion curves. It turns out that proper selection of incident angle and frequency is critical for guided wave generation in multi-layered structures. Theoretical dispersion curves greatly depend on adhesive zone thickness, layer thickness and material properties. It was possible to determine the adhesive zone thickness of an inhomogeneous multi-layered structure by monitoring experimentally the change of dispersion curves.