Index

18 May 2011

Pitman's Vol 14 - Types of Arches


Front Cover of Volume 14
Building Educator
Volume 14


by R Greenhalgh (Ed)

Published by Pitman & Sons Ltd
16th April 1927

No ISBN number

Extract from pages 648-650
There are many different forms of the arch in use at the present time, built up by a combination of different curves

The setting out of these will not present any great difficulty, once the student is thoroughly acquainted with the methods of connecting the different curves with their centres

Arches can be divided into three classes:
  1. Rough arches
  2. Axed arches
  3. Gauged arches
Arches can also be classified according to their shape, and the number of centres from which they are struck:

Semicircular arch
Segmental arch and
Flat (or camber) arch
One Centre
Pointed or Gothic arch
Two Centres

Semi-elliptical arch
Three, five, seven
and upwards


Tudor arch
Four Centres

Axed Arches
This term is applied where the voussoirs are cut to a wedge-shape, by means of the boaster, and trimmed to
an approximately true bed with the scutch. They may be rough axed, or fine axed, according to the class of work

The former usually applies to arches of sharp curvature, where strength is required and appearance is of little or no consequence

Where both appearance and strength are essential, and the arch is an ornamental feature, fine-axed work is generally used


Sem-circular brick arch
Image fromThe Heritage Directory
The arrises of the bricks are cut true and sharp, their beds being trimmed to a true surface and finished with a few rubs on the rubbing stone, so that the voussoirs can be bedded with a fine joint, usually about ⅛" to ¼", approx 5mm

Gauged Arches
Where a still finer finish is required, or special mouldings are to be cut on the face of the arch, rubber bricks are cut to shape by means of a wire saw, and the beds and arrises finished on the rubbing stone

The arch is then set in lime putty with a 1/32" joint, which is only 1mm

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