A symmetrical prestressed I beam having total depth 48 in, flange width 24 in., flange thickness...

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A symmetrical prestressed I beam having total depth 48 in, flange width 24 in., flange thickness 9.6 in, and web thickness 9.6 in. is to span 70 ft. It is post-tensioned using 18 Grade 270 in. diameter low-relaxation strands in a single tendon having a parabolic profile, with e = 18 in. at midspan and O in. at the supports. (The curve can be approximated by a circular arc for loss calculations.) The jacking force A = 618 kips. Calculate losses due to slip, elastic shortening, friction, creep, shrinkage, and relaxation. Express your results in tabular form both numerically and as percentages of initial prestress pi. Creep effects may be assumed to occur under the combination of prestress force plus self-weight. The beam is prestressed when the concrete is aged 7 days. Anchorage slip = 0.25 in., coefficient of strand friction = 0.20, coefficient of wobble friction = 0.0010, creep coefficient = 2.35. Member properties are as follows: Ac = 737 in2, Ic = 192,000 in4, q = c2 = 24 in., fc = 5000 psi, Ec = 4,000,000 psi, Es = 27,000,000 psi, wc = 150 pcf, and Cc = 2.65. %3D A symmetrical prestressed I beam having total depth 48 in, flange width 24 in., flange thickness 9.6 in, and web thickness 9.6 in. is to span 70 ft. It is post-tensioned using 18 Grade 270 in. diameter low-relaxation strands in a single tendon having a parabolic profile, with e = 18 in. at midspan and O in. at the supports. (The curve can be approximated by a circular arc for loss calculations.) The jacking force A = 618 kips. Calculate losses due to slip, elastic shortening, friction, creep, shrinkage, and relaxation. Express your results in tabular form both numerically and as percentages of initial prestress pi. Creep effects may be assumed to occur under the combination of prestress force plus self-weight. The beam is prestressed when the concrete is aged 7 days. Anchorage slip = 0.25 in., coefficient of strand friction = 0.20, coefficient of wobble friction = 0.0010, creep coefficient = 2.35. Member properties are as follows: Ac = 737 in2, Ic = 192,000 in4, q = c2 = 24 in., fc = 5000 psi, Ec = 4,000,000 psi, Es = 27,000,000 psi, wc = 150 pcf, and Cc = 2.65. %3D