Load cracks, also known as stress cracks, are structural cracks that occur under external loads.
This type of crack has a strong regularity, and accurate conclusions can generally be drawn through calculation and analysis.
A typical simply supported beam experiences stress cracks, with a normal section bending crack at the mid span, perpendicular to the beam axis and larger at the bottom and smaller at the top; The end is a diagonal section shear crack, starting from the support and pointing towards the concentrated load at the top of the beam.
Cracks in steel-concrete columns under axial compressive loads are distributed longitudinally along the column axis, with slightly denser cracks in the middle.
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