Fiber Reinforced Concrete with Natural Plant Fibers—Investigations on the Application of Bamboo Fibers in Ultra-High Performance Concrete

Abstract

Natural plant fibers represent a sustainable alternative to conventional fiber reinforcement materials in cementitious materials due to their suitable mechanical properties, cost-effective availability and principle carbon neutrality. Due to its high tensile strength and stiffness as well as its worldwide distribution along with rapid growth, bamboo offers itself in particular as a plant fiber source. In experimental studies on concrete beams reinforced with plant fibers, a positive influence of the fibers on the flexural behavior was observed. However, the load-bearing effect of the fibers was limited by the poor bond, which can be attributed, among other things, to the swelling behavior of the fibers. In addition, the plant fibers degrade in the alkaline environment of many cementitious building materials. In order to improve the bond and to limit the alkalinity and to increase the durability, the use of ultra-high performance concrete (UHPC) offers itself. Since no tests have been carried out, investigations on the flexural behavior of UHPC with bamboo fibers were carried out at the Institute of Concrete Construction of Leibniz University Hannover. The test results show a significantly improved load-bearing behavior of the fibers and the enormous potential of the combination of UHPC and bamboo fibers.

Fatigue resistance of concrete – Influence of time-dependent scattering of compressive strength

“…Fibre reinforcement, which is required in ultra-high-strength concretes [9,18,33], for example, tends to lead to a slight reduction in fatigue strength. This is due to the crack-inducing effect of the steel fibres at a maximum compression stress level 𝑆 max < 0.80.…”

Optimization and mechanism analysis of a compound additive for unfired bricks made of construction and demolition wastes

“…However, an excessive content of wood fiber resulted in inadequate dispersion of wood fibers in the bricks, creating a weak interface and deteriorating the compressive strength. The flocculated wood fiber strongly absorbed water, making the brick prone to microcracking upon freezing (Can Mark and Vincent, 2022). Therefore, the reasonable additional Cracks in unfired bricks with a fiber content of (A) 0%, (B) 0.1%, and (C) 0.2%.…”

Bruchlastwechselzahlen von druckschwellbeanspruchtem Beton unter Berücksichtigung der Streuung der Druckfestigkeit

“…Eine Faserverstärkung, die z. B. in ultrahochfesten Betonen erforderlich ist [3,15,32], verursacht tendenziell eine geringfügige Reduktion der Ermüdungsfestigkeit, die auf die rissinduzierende Wirkung der Stahlfasern bei einem Oberspannungsniveau S max < 0;80 zurückzuführen ist [33]. Gleichzeitig überbrücken die Stahlfasern die Mikrorisse, was einen positiven Einfluss auf die Ermüdungsfestigkeit hat, aber die rissinduzierende Wirkung in der Regel nicht aufhebt.…”