Project Details
Projekt
Ultraleichte, dünnwandige stabförmige Betonhohlbauteile unter Querkraft- und Torsionsbeanspruchung
Applicant
Professor Dr.-Ing. Martin Empelmann
Subject Area
Structural Engineering, Building Informatics and Construction Operation
Term
from 2011 to 2020
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 198434790
Truss members can fulfill the idea "Form Follows Force in an excellent way. because they can be adjusted to the distribution of stresses in a concentrated and optimized way. Examples from building practice are two-dimensional and spatial truss models, girders, columns, and mast constructions. Currently. these are erected in steel at most. Developments like high-performance concretes and innovative reinforcement concepts open the way to an increasing use of reinforced concrete for light truss structures.The design of force-flow-optimized structural members can be advanced by taking into account bionic analogies and abstractions of natural structures. because they inherit an evolutionary optimization.Following the principle ''Light Constructions with Concrete", bamboo is a brilliant and inspiring example for ultra-light. thin-walled hollow concrete members.Research to the bearing capacity and deformation behavior of thin-walled hollow reinforced concrete members under general loads (axial force. flexure, shear and torsion) is rare and only some test evidence exists. ln the 1st period of the SPP 1542, the structural behavior of thin-walled hollow reinforced concrete members was investigated under predominant axial force or bending moment. The results show that. one can achieve a high bearing capacity despite a low use of material and high demands on resource-efficiency.Yet, the structural behavior under shear and torsion remains still unclear. Indeed. first comparative tests on bamboo sections encourage hopes that for those load cases. a bionically motivated optimization could lead towards good results.Currently, experimental basics are missing to verify the behavior under shear and torsion for wall thicknesses that just match the size of the concrete cover in non-hollow concrete cross sections. Similarly, failure mechanisms and robustness of thin-walled concrete members are inadequately researched.Under theses aspects, stabilizing measures utilizing the bionic example of bamboo can be anticipated at the system level like molded stiffeners or bulkheads. which are typical for steel construction but not yet common for reinforced concrete. Existing design models for other groups of structural members should be verified and adjusted for the comprehensive data out of the new tests.In the current, missing knowledge stands against the use of ultra-light hollow concrete members in building practice. For general use of such hollow concrete members and constitutive to the works during the 1st period of SPP 1542 further leading theoretical and experimental research on the load conditions shear and torsion becomes necessary. This should be conducted within the frame of the suggested project.As the expected result, then theoretical and detailing foundations will be laid for design, calculation and construction of thin-walled hollow concrete truss members under general loading conditions.
DFG Programme
Priority Programmes
