ABSTRACT
The overall length and width of the test beam are 5.0 m and 1.6 m respectively. Figure 9 shows the details of SS-1. Four virgin steel, sheet piles whose yield strength is 450 MPa are assembled to fabricate the test beam. Its central area of 3.0 m is covered with reinforced concrete. Deformed bars of 16 mm in diameter are arranged along the axial direction of the beam at intervals of 150 mm, while those of 13 mm in diameter are arranged transversely at intervals of 130 mm. Their strength was about 360 MPa. The beams are modified their details according to Table 3. For SS-1 to SS-4, studs of 16 mm in diameter and 75 mm in length are used as shear connectors. They are arranged in 2 lines at intervals of 600 mm for SS-1 through SS-3 and in 1 line at intervals of 1200 mm for SS-4. For SS-5 and SS-6, J-shaped bars of about 230 mm in length and stirrups made of deformed bars of 13 mm in diameter are arranged respectively. In SS-5 and SS-6, the shear connectors are densely arranged near the end of the concrete. The test beam is strengthened by steel at its loading point and supports to prevent widenning or twisting. Initial stresses of 175 MPa and 290 MPa are introduced to SS-2 and SS-3 respectively before concrete casting. The initial stress simulates actual condition of a pipe which is induced fairly large stress due to external forces on corroded parts. The maximum size of aggregate of the concrete is 25 mm. Compressive strength of the concrete ranged from 21 to 30 MPa at the tests.
