The writer’s complaint is not that the theories of reinforced concrete are not fully developed.  They are developed too highly, developed out of all comparison with the materials dealt with.  It is just because reinforced concrete structures are being built in increasing numbers that it behooves engineers to inject some rationality (not high-strung theory) into their designs, and drop the idea that “whatever is is right.”

Mr. Porter has much to say about U-bars.  He states that they are useful in holding the tension bars in place and in tying the slab to the stem of a T-beam.  These are legitimate functions for little loose rods; but why call them shear rods and make believe that they take the shear of a beam?  As to stirrups acting as dowel pins, the writer has already referred to this subject.  Answering a query by Mr. Porter, it may be stated that what would counteract the horizontal cleaving force in a beam is one or more rods curved up to the upper part of the beam and anchored at the support or run into the next span.  Strangely enough, Mr. Porter commends this very thing, as advocated in the paper.  The excellent results shown by the test referred to by him can well be contrasted with some of the writer’s tests.  This floor was designed for 250 lb. per sq. ft.  When that load was placed on it, the deflection was more than 1 in. in a span of 20 ft.  No rods were curved up and run over the supports.  It was a stirrup job.

Mr. Porter intimates that the correct reinforced concrete column may be on lines of concrete mixed with nails or wires.  There is no doubt but that such concrete would be strong in compression for the reason that it is strong in tension, but a column needs some unifying element which is continuous.  A reinforced column needs longitudinal rods, but their office is to take tension; they should not be considered as taking compression.

Mr. Goodrich makes this startling remark:  “It is a well-known fact that the bottom chords in queen-post trusses are useless, as far as resistance to tension is concerned.”  The writer cannot think that he means by this that, for example, a purlin made up of a 3 by 2-in. angle and a 5/8-in. hog-rod would be just as good with the rod omitted.  If queen-post trusses are useless, some hundreds of thousands of hog-rods in freight cars could be dispensed with.

Mr. Goodrich misunderstands the reference to the “only rational and only efficient design possible.”  The statement is that a design which would be adopted, if slabs were suspended on rods, is the only rational and the only efficient design possible.  If the counterfort of a retaining wall were a bracket on the upper side of a horizontal slab projecting out from a vertical wall, and all were above ground, the horizontal slab being heavily loaded, it is doubtful whether any engineer would think of using any other scheme than diagonal rods running from slab to wall and anchored into each.  This is exactly the condition in this shape of retaining wall, except that it is underground.