Tragfähigkeit von schlanken Druckgliedern aus Beton und Mauerwerk

Bearing capacity of slender compression members in concrete and masonry. Theoretical analysis about the bearing capacity of slender structural members use for the derivation of the bearing capacity reduction factors differential equation or numerical analysis. The analytical formulation by Hansen [4] delivers with similar assumptions as by Haller [2] a design concept with direct derivation of the eccentricity‐curvature relation and the bearing capacity for linear and non‐linear stress distribution in the section. In this paper the bearing capacity with rectangular stress distribution in the section has been derived in similar way. Using the limit term it's able to differ between cracked and uncracked sections. Another limit term defines, whether the section is in the buckling or the compression area. Depending on state and area the bearing capacity can be calculated directly. On the compressed side of the section it can lead to material softening. The stress decrees at the edge enlarge the curvature of the column and reduce bearing capacity.     

Zur Tragfähigkeit von Ankerplatten in bewehrtem Beton

Load‐carrying capacity of anchor plates in reinforced concrete. For the load transmission into concrete constructions frequently anchor plates with welded studs are used. At the Institute of Structural Design two test series at reinforced concrete specimens were accomplished, which show that reinforcement decisively influences the load‐carrying capacity and the actually calculated design loads tend to underestimate the real resistance. On the basis of 27test results and supplementary FE analyses a first mechanical model based on the component method is presented, describing the load‐carrying capacity of anchor plates with welded studs in reinforced concrete elements.     

Zur Tragfähigkeit von druck‐ und biegebeanspruchten C‐Profilen aus Stahl

Die Regelungen und Nachweiskonzepte in den Stahlbaunormen DIN 18800 und Eurocode 3 zur Stab‐ und Gesamtstabilität von Bauteilen unter Normalspannungen sind weitestgehend durch Untersuchungen an I‐ und Kastenprofilen hergeleitet und verifiziert worden. Eine Übertragung und Überprüfung für davon abweichende Profilformen, im Speziellen für die hier behandelten C‐Profile, existiert nicht. Es wird ein geschlossenes, durchgängiges Bemessungskonzept vorgestellt, das es erlaubt, das Tragverhalten von Bauteilen mit C‐förmigem Querschnitt ohne längsaussteifende Querschnittselemente unter Druck‐ und/oder Biegebeanspruchung wirklichkeitsnah zu beschreiben und rechnerisch zu erfassen. Dabei wird den möglichen Stabilitätsproblemen – das heißt lokalem Plattenbeulen, globaler Stabstabilität und dem Zusammenspiel beider einzelnen Stabilitätsprobleme – besondere Aufmerksamkeit geschenkt. Ultimate loads of steel channel sections in compression and bending. Especially for members susceptible to global buckling or coupled instabilities the design rules in the relevant codes DIN 18800 and Eurocode 3 have been developed for and verified by research on I‐shaped or hollow sections. For deviant shapes, particularly the regarded channel sections, a transfer or verification of these design concepts does not exist. A comprehensive design method is presented, allowing to describe the load‐carrying behavior of channel‐shaped members without longitudinal stiffeners in compression and/or bending realistically. Special attention has been paid to the regards of stability problems, i.e. local and global buckling as well as a combination of both, the so‐called coupled instability.     

Tragfähigkeit von Spannbeton‐Fertigdecken auf biegeweichen Auflagern

Load bearing Capacity of Prestressed Hollow Core Slabs on Flexible Support Precast prestressed concrete hollow core slabs, the design and application of which are regulated in Germany by a general technical approval, are produced in production lines with a length of approximately 100 meters. In the longitudinal direction they are reinforced with tendons, in the transverse direction no vertical or horizontal reinforcement is arranged. If the width of the slabs is limited to 1.20 meters no transverse reinforcement is required. While the transverse load distribution is guidelined in the approval, the shear resistance of flexible supported slabs in connexion with a possible crack initiation due to the forced displacements is not regulated until now. In order to determine the actual failure mechanisms and the influence on the bearing capacity, a full scale test was carried out at the Kaiserslautern University of Technology by the Institute of Concrete Structures and Structural Design.