Intrados

The under, or concave, side of the voussoir is called the intrados or soffit, and the upper, or convex, side, the extrados of the arch. ❋ 1840-1916 (1913)

These spans are dictated by the coursing of the arches: the aim is to achieve high quality masonry with the height of the arch, from the intrados at the spring point to the extrados at the key-stone, contained within the height of two courses of earth blocks. ❋ Unknown (1995)

The drawing of the arches, on the elevation, also shows exactly how the thickness of the arches is included within a precise number of earth block courses, from the intrados at the springpoint to the extrados at the keystone. ❋ Unknown (1995)

The four sides of the mold formed the extrados, the intrados, and the two ends of the block; the other two sides being left open. ❋ Halbert Powers Gillette (N/A)

The reinforcement consists of arch and transverse bars; the arch bars are spaced 6 ins. on centers 2½ ins. from both extrados and intrados, and the transverse bars are spaced 24 ins. on centers inside both lines of arch bars. ❋ Halbert Powers Gillette (N/A)

The stability of such structures depends on the position of the line of pressure in relation to the extrados and intrados of the arch ring. ❋ Various (N/A)

The stability of such structures depends on the position of the line of pressure relatively to the intrados and extrados of the arch ring. ❋ Various (N/A)

It was determined to attempt to stop these leaks by the application of a water-proof cement coating on the intrados of the arch. ❋ James H. Brace (N/A)

Pressures due to the widening of mines beyond the limits of safety must not be taken as a controversion of this statement, as all arches have limits of safety, more especially if the useless material below the theoretical intrados is only partly supported, or is allowed to be suspended from the natural arch. ❋ J. C. Meem (N/A)

For instance, a soft clay arch of larger dimensions, under the condition described early in this paper, would undoubtedly stand if the rods supporting the intrados of the arch were keyed back to washers covering a sufficiently large area. ❋ J. C. Meem (N/A)

Again, on the following page, a somewhat similar qualification should be added to the sentence referring to the soft clay arch, that it would "stand if the rods supporting the intrados of the arch were keyed back to washers covering a sufficiently large area," by inserting the words, "unless creeping pressures (such as those encountered by the writer in his experiments) were exceeded." ❋ J. C. Meem (N/A)

In a flat arch the voussoirs are wedge-shaped, but the extrados and intrados are composed of straight lines. ❋ 1840-1916 (1913)

The rise of an arch is the height of the highest point of its intrados above the line of the impost; this point is sometimes called the underside of the crown, the highest point of the extrados being the crown. ❋ 1840-1916 (1913)

With their pommels cunningly affixed so that their points touched and interlaced, yet swung free, they lined the piers of the arch from base to span and all the graceful sweep of the intrados, a curtain of shimmering, trembling steel, barring the way to the Mystery beyond. ❋ Louis Joseph Vance (1906)

Norman arches resemble the doorways in having sub-arches recessed within an outer arch, the intrados often being decorated with mouldings such as the zigzag or the lozenge. ❋ Unknown (1892)

The silk curtains, she was sure, were hanging over the arch; for she remembered distinctly having noticed a large and very beautiful golden butterfly which had fluttered in from the terrace, and was flitting over the glowing folds that fell from the carved intrados to the marble floor. ❋ Unknown (1872)

Page 248 over the arch; for she remembered distinctly having noticed a large and very beautiful golden butterfly which had fluttered in from the terrace, and was flitting over the glowing folds that fell from the carved intrados to the marble floor. ❋ Augusta Jane (1867)

It consists of five parts: (1) Six concrete piers running the full width of the bridge upon which the structure was moved; (2) a steel framework up to E G, called the "primary bent"; (3) a separate timber portion below the heavy lines E I and W 'I'; (4) the "main staging" included in the trapezoid E I W 'I', and (5) the "upper trestle" extending from I I 'to the intrados. ❋ Halbert Powers Gillette (N/A)

One layer of felt with 4 "overlap to be nailed to lagging of inch boards, using tin washers on nails over the whole of the intrados of the arch before starting any concrete or placing any of the permanent felt and pitch water-proofing. ❋ F. Lavis (N/A)