Structural analysis programs usually compute a static model with cross sections given by the engineer or set to reasonable defaults. Any optimization of the structure with respect to a variable, for ...example weight/cost, is left to the experience of the engineer, usually because adding optimization capabilities to a structural analysis program is not trivial. Many optimization algorithms are available, each one with their own peculiarities, requirements, and performance. The variable to optimize is different for different projects such as material cost, construction cost, first eigen frequency and others. Adding to the complexity is the fact a static or dynamic analysis is computational expensive (time consuming) and thus the algorithms needs to be tuned to perform as few static analyses as possible. Optimization Computing Platform (OCP) is software developed at ISAAR-NTUA, which in combination with widely known structural analysis programs such as SAP2000 and ETABS, can optimize any structure with various algorithms, and with respect to various variables or a combination of them. Recently, OCP is actively developed to be program agnostic, so that it can be linked with any structural analysis program. The program gains painlessly mature and sophisticated optimization capabilities. In this case study OCP platform was linked with SCIA engineering, structural analysis and design software to provide addition optimization capabilities. To validate the software connection one structural examples is tested with very good results.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The construction of bridges with use of seismic isolation is a less-used concept in Slovakia and the Czech Republic. The concept of seismic isolation of bridges is a way of protecting bridge ...construction without damaging the pillars and substructure unlike the currently used methodology of consideration and development of plastic joints. When using this concept correctly, it is possible to prevent serious damage of construction and greatly reduce economic losses. Creation of a FEM (Fine Element Method) model, that is capable of correct description of the bridge behavior during a seismic event is often problematic. In this paper, the features of designing and modeling of bridge constructions with use of seismic insulation based on elastomeric bearings are presented. Furthermore, the calculations of stiffness constants required for numerical modeling are presented as well. In this paper are described methods of modeling of seismic isolations in a commonly and commercially available FEM based software. The work also contains a comparison of possibilities as well as limits of these programs. We further present recommendations for correct modeling by use of nonlinear material properties or elastic bonds between elements.
Creating an analytical model for a bridge structure is one of the most challenging engineering tasks. For the design of all supporting elements and in all design situations., It is often necessary to ...create several models. One of the common modeling problems is related to the area between the bridge girder and piers. A Correct representation of the upper and lower structure interaction is particularly important in case of seismic design and the subsequent design of the piers. With a suitably built analytical model, it is possible to significantly reduce the horizontal effects from the upper structure and consequently, to reduce the shear strain of the piers. This contribution discusses the particularities of designing and modeling of bridges with elastomeric bearings. Further follows the description of the main methods for designing such structural elements in three commonly available commercial software based on the Finite Element Methods, hereinafter referred to as FEM. At the end of the paper the individual software options are compared.
This paper presents design, development and application of a finite-element based least cost optimisation model (named ResOp) for reservoirs using a Genetic Algorithm. The model makes use of site ...specific parameters not normally considered at outline design but which are usually available; such as site plan limits, maximum height above ground level and geotechnical conditions.
The results show that such site based parameters have a significant effect on cost which can be easily incorporated at outline design stage without making expensive changes at the detailed design stage of a project. This would also be suitable when considering a selection of sites. Current cost models in the industry are too basic and should become more site specific.
The design of a reservoir constructed in Cornwall was compared to an optimised reservoir design using ResOp. The results show a potential for substantial savings to be made. The aspect ratio and shape found reasonable correlation to best practice, but the developed model suggests a more refined optimisation approach which includes site variables.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The paper deals with construction design of special device which is used for launching the TMS temporary bridge set. The device is used with the vehicle that is used to push the bridge structure over ...the obstacle. The device is frame construction made of steel and connected to end bay of the bridge by the pins. Dismountable, portable and easy to maintain were the main requirements for the device. Paper presents the reasons why this device is designed by this way and there is also made suggestion for static assessment.
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