The Essesntials of Reinforced Concrete Design. Part VIII. - Dispersion Effect of Slabs Upon "Point"

The accompanying photograph is of a reinforced-concrete bridge, carrying the roadway over the River Alde, and is part of a scheme prepared by the County Surveyor, Mr. W. Jervis. The superstructure above the normal water level is in Portland Cement, and the whole structure is carried on twenty Ciment Fondu piles. A rather interesting feature of this bridge is the construction of the 4/13 ft. counterfooted walls; these are properly bonded into, and are part of, the bridge; in fact, the piers seen at the corners are really part and parcel of these walls. The walls at their outer ends are free, and can slide on the pile heads, a bituminous pad being placed between the pile cap and the underside of the wall base to allow for free movement. The wall is prevented from sliding outward from the roadway by being keyed into the inner pile cap.

THE attempt to give a ferro-concrete or steel framework " truthful " expression is beset with many difficulties. These difficulties, however, are, of course, not practical, but purely aesthetic. If one altogether ignores the aesthetic aspect of the problem there is nothing to prevent one from leaving all the girders or other constitutional members bare and then pretending that the result is satisfactory. There are a few theorists, chiefly to be found among the ranks of architects, who hold the doctrine that the candid expression of structure must inevitably lead to beauty,- but one is correct in saying that engineers for the most, part have no such illusions, and are quite as ready to cover up their steel girders as they are to provide decorative, casements for machinery of all sorts. The modern railway locomotive, for instance, may be cited as an example of a composition in which a very definite, and indeed successful attempt has been made to achieve a certain formality which is not the result: of the naked display of structure. The cylindrical boiler, emphasised in front by the funnel, which feature is itself invariably punctuated by a brass rim or by other means, is well balanced by the canopied hood of the driver, and in between these two features rests a smooth dome-like protrusion coficealing valves beneath it, and it self often showing a surface of polished brass. But while the practice of engineers shows that they are quite prepared to cover up machinery or other portions of the structures erected by them, this act of concealment should be governed by certain conventions which cannot be defied without the creation of an artistic abuse. For instance, the very common practice of superimposing shop fronts upon sheets of glass, without there being any visible support for the solid wallage is an anomaly. Yet the practice continues, and even quite reputable architects are guilty of it. Of course, these latter may say, in extenuation of their conduct, that they were obliged to accede to the demands of their clients, and that they themselves, if left to their own devices, would never have countenanced such an architectural solecism. One would like to know, however, what steps, if any, these complacent architects took in order to convince their clients of the impropriety of resting a considerable height of stone or brick wall upon what appears to be a ground floor storey of glass. It is quite easy to imagine the nature of the arguments which the client would bring forward on such an occasion. He would point out that it was necessary for his business to have the widest possible extent of window for the display of his merchandise, and he would say that in this instance the widest possible extent of the street frontage is nothing less than the whole extent, and he would claim his right to insist that no column, pier or abutment should be allowed to break up the surface of his great glass shop-front. Nor need one criticise him too severely for ha

There are many interesting problems connected with the construction of tube railways; the following has reference to forming the modern escalator entrances to the stations. J.P. Clark