44 



REINFORCED CONCRETE CONSTRUCTION 



imately the directions of the maximum stresses for a beam 

 uniformly loaded. It should be noted that the common theory 

 of flexure gives the unit stress correctly at the important section 

 of maximum moment and also for the extreme fibers in other 

 sections, since at these points the shear is zero. Where the 



Lines of maximum tension 

 Lines of maximum compression 



FIG. 16. 



shear is not zero an inclined stress is the result and our flexure 

 formula gives only the horizontal component of this 'stress 

 namely, the fiber stress. 



By the use of the above formulas the value of the maximum 

 tensile (or inclined) stress at any point may be determined, 

 x 



FIG. 17. 



also the angle K it makes with the horizontal. The stress t, Fig. 

 17, produces the greatest intensity upon a plane perpendicular 

 or normal to its line of action namely, upon the plane be. 

 In the same manner considering point A', it is a comparatively 

 simple matter to derive the magnitude of If and the angle K' 

 it makes with the horizontal. The stress t' causes the greatest 

 stress on the inclined plane 6V. 



