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One of the main problems in control is that the overwhelming number of physical quantities cannot be measured directly. Hence, there arise so-called inverse problems on the determination of physical quantities from the results of their manifestations. In the mechanics of a deformable solid there is a problem of obtaining material properties at all stages of deformation and especially at the overcritical stage. In this paper, we formulate and solve the inverse problem of finding the tensile diagram of a material element from the diagram of the dependence of the bending moment on the curvature of a rectangular beam under pure bending. [ABSTRACT FROM AUTHOR]

The paper presents a shear strength model used to evaluate information of interest from shock experiments aimed at studying the properties of the hardened 30KhGSA steel and the MA14 magnesium alloy subjected to low- and high-intensity loadings. The model parameters are adjusted by experimental deformation curves obtained from static and dynamic tests at different temperatures and the data from shock experiments to account for strength variation at high strain rates. The simulation of low-intensity loading tests helped to improve the description of elastic-plastic properties and to adjust our failure model. The data from the shock experiments with high-intensity loading of 30KhGSA steel samples and unloading of the shocked samples in window materials were used to verify the phase diagram and the kinetics of direct and inverse phase transitions, and to determine more exactly how the changed phase state influences the strength. The model presented here has allowed us to reproduce the complicated strength behavior of the MA14 alloy at different loading intensities. [ABSTRACT FROM AUTHOR]

This paper deals with the development and approbation of a computational model of damage accumulation in a vertical steel tank at the non-uniform foundation subsidence. The object of research is structure behavior at the survivability stage, namely, the character and sequence of damage initiation and accumulation (elastic-plastic strain, bottom and wall buckling) in the tank structure. [ABSTRACT FROM AUTHOR]

The paper presents an automated system for monitoring the deformation state of a building complex. The measurement unit of the system records the vertical displacements of a number of bearing columns using the hydroleveling method. In the analytical block, numerical modeling of deformation processes in the subsoil–foundation– building system is performed. The information on the foundation settling obtained during monitoring is used to specify the boundary conditions for modeling the stress-strain state of the structure. Thus, the deformation response of all structural elements to uneven vertical settling of supporting columns is evaluated. The monitoring system has been working since 2010 and it has demonstrated high efficiency. [ABSTRACT FROM AUTHOR]

With advances in computer capabilities, cost of sheet metal forming has being reducing mainly due to the reduction of trial and error approaches. At the moment, a complete process can be simulated on computer and appropriate forming conditions optimized before actual industrial forming process is carried out. While formability predictions have improved, the problem of springback exhibited by most metal, including aluminum alloy AA6111-T4, after forming persist and often leads to significant part fit-up problems during assembly. There are a number of factors that affect springback and perhaps the most significant one is constitutive equation. In this paper springback predicted by six advanced kinematic models are evaluated. In addition an improved constitutive kinematic model is presented. It is shown that by adding stress correction term (SCT) to Armstrong-Frederick model a relatively simple and yet accurate stress prediction could be obtained. The SCT was developed with the assumption that the yield surface remains convex, yield center depends on translation, size and shape variations of the yield surface. The model is implemented in a commercial finite element code (ABAQUS/Standard) via its user material interface (UMAT). Numerical simulations of U-bending were performed using automotive aluminum sheet material (AA6111-T4). It was noted that springback has inverse relationship with residual stress. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]