Annotation

The article presents results of lightweight concrete elements, reinforced with fibre-reinforced plastic rebar of various widths. Bearing capacity and stress-strain behavior of the complex lightweight concrete elements are investigated and compared experimentally. Four experimental samples have been made in order to study bending complex lightweight concrete elements, reinforced with fibre-reinforced with plastic rebar of various widths. All experimental samples were made with a 160x160 mm cross section. One of them was not reinforced (B-1) and three – reinforced with fibre-reinforced plastic rebar of the width of 5 mm (B-2p), 10 mm (B-3p) and 35 mm (B-4p). The total length of the samples was 660 mm.

Examination of the lightweight concrete samples was carried out on a testing bench, located in the laboratory of building structures. Experimental samples were based on two supporting structures: movable and stationary. In the places of applied load, one was fitted to the metal details, and the traverse, the ring dynamometer for measuring of the applied loads, and the hydraulic jack to create loads were placed on the tops of those details, and a clock type indicator for measuring of the deflections was mounted in the middle of the experimental sample.

As a result of the experimental studies, the greatest effect concerning increase of the bearing capacity and reduction of the stress-strain behavior is observed in the experimental sample B-2p, reinforced with a fibre-reinforced plastic ribbon of 5 mm width, so that the bearing capacity of the experimental sample B-2p is 1.76 times higher than the B-2p sample, and 1.27 times higher, as compared to the B-4p sample and 1.87 times higher, as compared to the unexpressed experimental sample B-1. The smallest stress-strain behavior under the same loading rates is observed in the experimental sample B-2p, which has been reinforced by the ribbon of 5 mm width. Comparing the experimental samples for the loading F = 20.47 kN, the stress-strain behavior in B-2p is practically the same while comparing to B-3p; it is 1.08 times lower than B-4p and B-1.

The most effective version of the reinforcement was secured by the ribbon of 5 mm width due to the experiments, carried out with the tested samples of the section of 160 x 160 mm and the length of 660 mm, made of aerated concrete blocks and monolithic slag of expanded clay concrete.