Krisztian Hincz

Budapest University of Technology and Economics · Department of Structural Mechanics

The research deals with the analytical, numerical and experimental analysis of an air-inflated beam. The paper introduces the experimental setup of the 4-point bending analysis of the inflated beam and the investigated air-inflated beam prototype. The membrane forces in the beam at different external loads, the wrinkling load (the smallest load tha...

The use of textile membranes in architecture and civil engineering has increased rapidly in the last decades. Membrane structures are lightweight, economic structures with unique shapes. At the same time, their structural analysis is particular compared to the analysis of conventional structures. The form-finding procedure, the large displacements...

Background: Some medical and technological tasks lead to the geometrical problem of how to cover the unit circle as much as possible by n congruent circles of given radius r, while r varies from the radius in the maximum packing to the radius in the minimum covering. Proven or conjectural solutions to this partial covering problem are known only fo...

The Computational Fluid Dynamics (CFD) analysis of wind actions on a cube and on the hyperbolic surface of a mast-supported tensile structure is presented. As standard in Computational Wind Engineering (CWE) the models were analyzed in incompressible fluid flow. For the CWE study, the Reynolds-Averaged Navier-Stokes (RANS) equations were solved wit...

This paper presents a study on the mechanical behaviour of thin membranes modelling the common 32-panel soccer balls. Most soccer balls are fabricated of synthetic flat panels subject to an internal pressure. Unlike most tensile structures such as tents, balls form closed surfaces, which are expected to comply strict conditions, most importantly re...

How must n equal circles of given radius be placed so that they cover as great a part of the area of the unit circle as possible? In this paper the case of n = 4 is investigated. It is known that the centres of the four equal circles form a square in both the maximum packing and the minimum covering configurations, and it is expected that for radii...

Conventionally, the pressure coefficients of tensile membrane structures are determined in wind tunnels on rigid models and the effect of the typically large deformations of the membranes on the pressure coefficients is not taken into account. The aim of the current research is to analyze the effect of the displacements of membrane structures on th...

How must n equal circles of given radius be placed so that they cover as great a part of the area of the unit circle as possible? To analyse this mathematical problem, mechanical models are introduced. A generalized tensegrity structure is associated with a maximum area configuration of the n circles, whose equilibrium configuration is determined n...

How must n equal circles of given radius r be placed so that they cover as great a part of the area of the unit circle as possible? In this Part II of a two-part paper, a conjectured solution of this problem for n = 5 is given for r varying from the maximum packing radius to the minimum covering radius. Results are obtained by applying a mechanical...

The volume enclosed by a membrane forming a convex polyhedron increases for inflation even if the deformation is inextensional. Here, in the case of a cube, the following problem arises: How must the surface of a cube be deformed inextensionally so that the volume of the obtained polyhedron will be as large as possible? In the paper, this problem i...

The pressure coefficient field of a mast supported membrane structure was determined by the help of wind tunnel tests and on the basis of Design Codes number MSZ EN 13782 and number MSZ 15021/1-86. The membrane forces in warp and weft (fill) directions were calculated on the basis of the experimental and the code-based pressure coefficient fields....

This paper introduces some results of the optimization of tensile roofs suspended from arches by the help of different suspension systems. In the case of "conventional" suspension the individual suspension cables connect the breakpoints of the ridge cables of the tensile roof with the joints of the supporting arches directly. In the case of block a...

The paper presents the comparative analysis of cable net roofs supported by truss arches with block and tackle suspension system. The effect of the friction (between the pulley and its shaft) on the internal forces of the supporting arches and on the displacements of the cable net roofs has been analysed. Structures with different number of support...

A numerical procedure for the static analysis of arch-supported tensile structures with block and tackle suspension system is presented. The procedure, based on dynamic relaxation, is suitable for a structural analysis both in the prestressing process and in a final state under external loads. The friction between the pulley and its shaft is also t...

There is a growing need for lightweight tensile structures for covering large areas without inner support. The structural analysis of cable net structures is a special engineering problem, third order theory is used because of the large displacements. During the analysis of cable net structures, different equilibrium shapes have to be determined. T...

Most soccer balls are made of stitched leather or synthetic panels with a bladder inside. The initial configuration of the balls can be represented by polyhedra in the three dimensional space. For the numerical evaluation of the sphericity of the ball, a method previously proposed by the first author is used in this paper. Following previous studie...

This paper deals with the parametric analysis of special arch-supported cable net structures. Based on an invention of Kolozsváry [5], the cable net is suspended from the arches with block and tackle suspension system. The aim of this special suspension system is to minimize the bending moments in the supporting arches by converting the random mete...

This paper introduces special arch-supported tensile structures, based on a new invention, which makes possible building structures with clear spans longer than allowed by existing technologies. The invention converts random roof loads (wind and snow) into uniform, symmetric arch loads using a unique suspension system, based on the well known princ...

The dynamic relaxation method is applied to membrane analysis using an eight-node quadrilateral element. The element uses second order shape functions to approximate the geometry of the structure. The element is based on the element of Gosling and Lewis [Gosling PD, Lewis WJ. Optimal structural membranes—I. Formulation of a curved quadrilateral ele...

The paper reports about a procedure, developed for the long-term analysis of prestressed membrane structures. The procedure is based on the Dynamic Relaxation Method [1] and uses visco-elastic material model. The governing equations of the procedure and the numerical results of an analysed structure is introduced.

Our research can be divided into two different areas according to our main objectives. On the one hand, we made experiments to learn as much as possible about the long-term behavior of the PVC-coated polyester textile; the most commonly used material type for the construction of tents in Hungary. On the other hand, we developed a procedure for the...

Cutting patterns of a simple form of a tent, so called 'Chinese hat', were analyzed in the paper. Stress distributions in prestressed membrane structures, according to cutting patterns prepared by the help of various numerical methods, were compared. A recently developed computer program, based on the dynamic relaxation method was used for the nume...

This paper describes a technique for the determination of cutting pattern of prestressed tent structures and for the rebuilding of the tents from the cutting pattern. The basis of the calculation of the shape and the internal forces in the tent is the dynamic relaxation method.

This paper describes a method for the analysis of prestressed tent structures. With the help of this method, it is possible to take into account the effect of the approximations, which have to be used during the cutting pattern generation. During the determination of the real shape of the tent and during the structural analysis, it is possible to t...