Bending behavior of high-performance, micro-reinforced concrete

摘要

The development of high-performance concretes enables a reduction of the dimensions of concrete members. If these dimensions are reduced down to the size of 30-50mm, a conventional reinforcement cannot be used and alternative concepts are required. In this case, micro-reinforced concrete, internationally also known as ferro-cement, can be used advantageously. In this paper, results of bending tests on micro-reinforced beams made of high and ultra-high performance concrete with varying micro-reinforcement ratios and orientations are presented. Furthermore, approaches based on DIN EN 1992-1-1 (EC 2), allowing the determination of a minimum micro-reinforcement ratio as well as the secure assessment of the ultimate flexural strength of micro-reinforced beams were developed based on the test results. In addition, a finite element analysis of the beams is shown, enabling a precise recalculation of the load-bearing behavior as well as the ultimate flexural strengths obtained during the tests. Overall, the described experimental and theoretical investigations are a valuable contribution towards the development of a general design approach for thin-walled, micro-reinforced concrete members.