A Practical Theory of Voussoir Arches

a₁ abutment angle of friction apex applied arch balanced arch ring b₁ base of pier beam Bland's bricks bridge centre of gravity centre of pressure cloth column components compressibility considered construction contour curves corresponding crown and springing crown joint curve of pressures depth of joint depth of keystone drawing edge of joint edge of pier Engineer experiments extrados form of arch Gothic arch half arch hence horizontal force horizontal thrust Hypsometry Illustrated inner edge inner third joints of rupture limiting curves line of pressures lower edge method middle third minimum mortar NOSTRAND'S PUBLICATIONS outer edge P₁ P₂ pass a curve point of application practice pressures passes proper limits R₁ rafter resultant rolling load Scheffler side sliding span spandrel springing joint stability stone sultant summit suppose surface symmetrical Telegraphy theory thick tical tion Treatise U. S. Navy vertical weight