Under section of sustained transverse loads, compressive stress distribution in concrete changes with time, axial force is a measurement of forces required to pull something such as rope, wire or structural beam to point where it breaks compression force is application of power, pressure and erection against an object.

Floors roofs not supporting and not attached to non structural element likely to be damaged by large deflection such deflection is considered as immediate deflection due to live load, deflection limitations are given as (span/180).

The computations of short term or instantaneous deflections, which occur immediately after transfer of prestress and on application of loads is conveniently done by Mohr?s orem from certain surveys it is concluded that maximum deflection should be noted including with limiting deflection span ratio.

According to ACI: 318-1989 uses a similar approach whereby an additional long term deflection resulting from creep and shrinkage of flexural members is determined by multiplying immediate deflection caused by sustained load.

Experimental investigations have shown that micro cracks develop at a tensile stress of about 3n/mm² which is invisible to naked eye, on furr loading cracks are first visible at flexural tensile stresses between 3.5 and 7n/mm² higher values generally correspond to beams with well bonded steel distributed close to tensile face as in case of pretensioned members.

The deformation of prestressed members change with time as a result of creep and shrinkage of concrete and relaxation of stress in steel, practically change in stress obtained is relatively very small and hence it may be assumed that at constant stress formation of creep occurs in concrete.

The prediction of time dependant deflections is complicated in case of cracked members due to redistribution of flexural stresses, according to Neville an exact solution results in nonlinear integral equations for which no closed solution is available is ? = ?/1+50??
?? = (A?_s/bd) at midspan, A?_s = area of compression reinforcement, b = width of section, d = effective depth, ? = time dependent factor.

Mohr?s second orem states that
Intercept, a = (moment of area of bending moment deflections/flexural rigidity), a = AX/EI,
a = deflection at centre for symmetrically loaded, simply supported beam (since tangent is horizontal for such cases), A = area of bending moment deflection between A and C, x = distance of centroid of bending moment deflection between A and C from left support, EI = flexural rigidity of beam.

Several methods have been proposed to evaluate curvature under simplified assumptions and important ones are attributed by Buseman, Mchenry, Douglas, Corley, Sozen and Siessand and numerical solutions developed ignore influence of tensile concrete zone on strain distribution in section, which considerably effect deflection equation for long term deflection of cracked members.

The deflection of beam with parabolic tendons having an eccentricity e at center and zero at supports is given by a = ?5PeL²/48EI, a beam with a parabolic tendon having an eccentricity e₁ at centre of span and e₂ at support sections and resultant deflection at centre is obtained as sum of upward deflection of a beam with a parabolic tendon of eccentricity e₁+e₂ at centre and zero at supports and downward deflection of a beam subjected to a uniform sagging bending moment of intensity pe₂ throughout length, resultant stress becomes a = PL²/48EI(-5e₁+e₂).