column is due to the inherent weakness of brittle material in
compression when there are sharp corners which may spall off.

Mr. Worcester says that several of the writer's indictments hit at
practices which were discarded long ago, but from the attitude of their
defenders this does not seem to be true. There are benders to make sharp
bends in rods, and there are builders who say that they must be bent
sharply in order to simplify the work of fitting and measuring them.

There are examples in engineering periodicals and books, too numerous to
mention, where no anchorage of any kind is provided for bent-up rods,
except what grip they get in the concrete. If they reached beyond their
point of usefulness for this grip, it would be all right, but very often
they do not.

Mr. Worcester says: "It is not necessary that a stirrup at one point
should carry all the vertical tension, as this vertical tension is
distributed by the concrete." The writer will concede that the stirrups
need not carry all the vertical shear, for, in a properly reinforced
beam, the concrete can take part of it. The shear reinforcement,
however, should carry all the shear apportioned to it after deducting
that part which the concrete is capable of carrying, and it should carry
it without putting the concrete in shear again. The stirrups at one
point should carry all the vertical tension from the portion of shear
assumed to be taken by the stirrups; otherwise the concrete will be
compelled to carry more than its share of the shear.

Mr. Worcester states that cracks are just as likely to occur from stress
in curved-up and anchored rods as in vertical reinforcement. The fact
that the vertical stretching out of a beam from the top to the bottom,
under its load, is exceedingly minute, has been mentioned. A curved-up
bar, anchored over the support and lying near the bottom of the beam at
mid-span, partakes of the elongation of the tension side of the beam and
crosses the section of greatest diagonal tension in the most
advantageous manner. There is, therefore, a great deal of difference in
the way in which these two elements of construction act.

Mr. Worcester prefers the "customary method" of determining the width of
beams--so that the maximum horizontal shearing stress will not be
excessive--to that suggested by the writer. He gives as a reason for
this the fact that rods are bent up out of the bottom of a beam, and
that not all of them run to the end. T