Basic principles of prestressed concrete

Obviously, at this point, the pre stress will completely cancel out the tensile stress generated by the load at the lower edge of the section.

Of course, if e and Np are not equal to the above values, the stress at the upper and lower edges of the cross-section will also have different values.

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But the overall trend is that the lower edge tensile stress caused by the load is partially or completely offset by the pre stress.

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