TINJAUAN KUAT GESER SENGKANG ALTERNATIF DAN SENGKANG KONVENSIONAL PADA BALOK BETON BERTULANG

Abstract

Reinforced-concrete requires bending and shearing reinforcement. Bending reinforcement is used to detain bending moment, whereas shearing reinforcement (sengkang) is used to detain shearing load. Generally, vertical shearing reinforcement has a function to detain shearing load. Whereas horizontal shearing reinforcement is not calculated in detaining load force occured on a beam. Vertical shearing reinforcement prevents a beam to apart due to shear force. This research was done to find whether horizontal shearing reinforcement (alternative reinforcement) is required in construction. The objectives of this research is to know the maximum shear load and the difference between alternative reinforcement and conventional reinforcement in reinforced-concrete beam. This research was carried out in 5 steps, i.e., preparation of research equipment and material; inspection of research material quality; provision of test materia; concrete strength compression test and reinforced-concrete beam shear compression test; and analysis and discussion. The research took place at Construction Material Laboratory at Civil Engineering Department, Faculty of Engineering UMS. The number of object test were 12 pieces, and 2 pieces of object test were used for each variation. The space variation used were 40 mm, 80 mm and 120 mm, with reinforcement weidth 15 cm and height 20 cm, and beam length 150 cm. According to analysis result, it is known that maximum shear force occurred in a reinforcement with space 40 mm, i.e., 1797,7 kgs for conventional reinforcement and 1735,2 kgs for alternative reinforcement. Whereas, maximum shear compression is 766,5 kgs for conventional reinforcement and 704 kgs for alternative reinforcement, and the biggest difference between conventional reinforcement shear compression and alternative reinforcement shear compression is 28,31% which occurred in a reinforcement with space 80 mm, and the difference of shear load is 8,49%. Generally, it can be said that shear strength between conventional reinforcement and alternative reinforcement is relatively equal.