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-The research investigation was carried out to determine the effect of different modes of continuity of tension reinforcement bars on the flexural strength of reinforced concrete beams. Nine (9) full size beams (2150 mm × 250 mm × 180 mm) were cast with 2 numbers of 16 mm diameter high yield bars in tension and 10 mm diameter high yield stirrups at 100 mm centres at the shear spans. Three (3) beams each were cast with full length bars (reference), lap-spliced bars and butt-welded reinforcement bars in tension. Twenty-seven (27) 150 mm cubes were also cast to monitor concrete strength. The beams and cubes were cured for twenty-eight (28) days and tested in flexure under four points bending system and in compression respectively. The test results showed that full length bars, lap-spliced and butt-welded bars had an average moment capacity of 25.54 kN·m, 19.16 kN·m and 10.64 kN·m respectively. Lap-spliced beam gave a higher moment of resistance compared to the beams with butt welded steel reinforcing bars. The average midspan deflection of butt welded reinforcement was smaller than that of in the beam with lap spliced type of continuity. It was concluded that continuity using lap spliced bars in tension is more effective and efficient than butt welded continuity. 58.34 %, 25.00 % of the moment capacity of beams with full length reinforcement was lost by using butt weld, without a coupler, and lap spliced bars, respectively.

The paper reports an experimental research investigation carried out to compare the bond resistance and efficiency of various coating materials, including epoxy, which were sourced locally. Thirty-four full size beams of varying lengths and sectional dimensions, with lap spliced bars in constant moment region were cast and tested in a four-point bending system. Three varying high yield diameter bars 16 mm, 20 mm and 28 mm were coated with various coating materials such as epoxy, chlorinated rubber, tyrolin, vinyl chloride and zinc ethyl silicate in an attempt to find a cheaper but effective coating material than epoxy. The ultimate moment from the tests were used to determine the stress developed in the steel rods. The bond efficiency, i.e. the ratio of test bond stresses and the theoretical bond stresses was used for the comparison of the various coating materials. The bond resistance and efficiency of vinyl chloride coated bars were found to be higher than that of epoxy and other materials, in all the beams tested. Statistically, there appear not to be significant difference between the bond efficiency of epoxy and vinyl chloride.