e = 410, length = 30m, stress induced = 1000
Slope of cable ? = (4e/l) = ((4×410)/(30×1000)) = 0.0547.

The method of calculating crack width is of considerable importance in checking limit state of cracking at service loads and it is well established that width of crack primarily depending upon stress in reinforcement is also influenced by cover and type of reinforcement.

Load combinations: Dead and imposed (and earth and water pressure) ? Dead beneficial is 1.0, Dead and wind (and earth and water pressure) ? Dead beneficial is 1.0, Dead and wind and imposed (and earth and water pressure) ? Dead beneficial is 1.2.

Actual self weight of beam and girder = 8.8kn/m, span = 30m
Minimum moment M_min = 990knm, Design working load = 19.8kn/m,
Working moment M_d = (0.125×19.8×30²) = 2230knm.

Range of stress f_br = (?f_ct-f_cw) = (0.85×15-0) = 12n/mm², f_tr = (f_cw ? ?_fu) = (17-0.8x(-1)) = 17.8n/mm², f_ct = 15n/mm², f_cw = 17, f_tw = 0, f_u = -1n/mm², ? = 0.8.

It is well established that fully prestressed members due to ir higher rigidity have a lower energy absorption capacity in comparison with partially prestressed members, which exhibit a ductile behavior.

In partially prestressed members limited tensile stresses are permitted in concrete under service wads with controls on maximum width of cracks and depending upon type of prestressing and environmental conditions and use of partial prestressing was first proposed by Emperger in 1939 and furr progress in this field was mainly due to sustained work of abeles, Goschy and ors and west German code DIN 42227 has provided for partial prestressing even before C.E.B-FIP provisions were introduced in 1970.

Bennelt has recently proposed a simple formula for estimating self weight of girder by considering several influencing parameters
w_min/w_ud = KD_cg?(L/h)L/f_cu(d/h)²
w_min = Self weight or minimum load, L = effective span, K = numerical constant, D_c = density of concrete member, g = acceleration, ? = moment coefficient, h = overall depth of girder,
w_ud = Ultimate design load.

The value of numerical constant K is between 6 to 7.5 for rectangular sections and I section girders of short spans, while it takes a value between 4 and 5 for flanged T or I section girders of long spans for self weight equation.

p = (A(f_infZ_b+f_subZ_t)/Z_t+Z_b)
F_inf = ((f_tw/?+(m_q+m_g)/?z_b)) = (0+ (26.36×10⁶/0.8x230x10⁴))
F_sup = (f_u ? m_g/z_t) = (-1 ? (3.86×10⁶)/(230×10⁴)) = -2.68n/mm².