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bond, with one stopped end, the governing line in each case being marked G.

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Figs. 34, 35, 36, 37, 38, 39, 40, and 41 show the treatment of reveals; A in each case being termed the reveal, and B the

The thickness of wall, depth of reveal, and plan of recess

recess.

G

G

Fig. 32.

Fig. 33.

will be gathered from the figures: Figs. 36 and 37 are illustrations of splayed jambs; Figs. 42, 43, 44, 45, 46, and 47 are plans of alternate courses of 2, 23, and 3-brick square piers.

In junctions of walls, as Figs. 48, 49, 50, and 51, there are two rules to bear in mind : First, that the stretching courses of the thicker wall must open to receive 2" or the multiple of 21"

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of the alternate courses of the thinner wall. When the latter consists of an even multiple of a brick, then it is always the heading course that is let in, and this course will project 21" from the major wall. Secondly, that the remaining courses of the minor wall will butt against the heading courses of the thicker wall; the

A

B

FIG. 48.

Fig. 49.

centre of one of these headers on each side of the thinner wall coinciding with the wall-line, as in AB, Fig. 49. Figs. 52, 53, 54, and 55 illustrate the bonding of obtuse and acute angles. The rules for these will be similar to those for square angles, with

FIG. 50.

FIG. 51.

the exception that in the obtuse angle a squint brick, S, is used for the quoin, and that the internal angle is bonded alternately with a bird's-mouth brick, B, and a joint. It will be noticed that the squint brick is 6%" on the stretching, and 21" on the heading face; the 21" return being followed immediately by a closer, thus maintaining 21" bond. Again, it would be advisable to make a tracing of one course and place it over the course above or below, to ascertain the correctness of the bond.

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Flemish Bond (Double).—This is considered by many to be superior in appearance to English. It is certainly not so strong, and the only advantage that can be brought forward in its favour is that, owing to the want of proper relative proportion between the headers and stretchers of most classes of bricks, the use of the alternate header and stretcher upon the same course renders it far easier to keep the perpends than when using alternate courses of headers and stretchers. The principles underlying correct bonding

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in English must, as far as practicable, be applied to Flemish bond, though the rules cannot be adhered to as rigidly as in the former. Thus in the 14-brick wall (Figs. 56 and 57) the quarter-bonding stretcher on the internal angle projects 69"; this is also the position of the governing line. Again, in the 2-brick wall, while, as in English, the quarter-bonding on the inside angle is obtained by means of a header, for the sake of keeping the transverse joints unbroken, the bat A is introduced, corresponding as far as possible with the stretcher B. Figs. 56, 57, 58, and 59 are plans of

С

alternate courses of 1 and 2-brick walls in double Flemish bond, with one stopped end.

The mode of finishing at C, Fig. 59, is strictly Flemish, but for the sake of strength this should be treated as in English bond.

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If tracing-paper be used, as already advised, it will be seen that there are several instances of joint upon joint, thus proving the inferiority of the bond, in point of strength, to English.

Double Flemish bond is not used in walls of very great thickness, neither is it often used in cross or junction walls, but the

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example given in Figs. 60 and 61, may occur in practice. Here an 18" wall, English, is intersected by a 1}-brick wall, double Flemish. The rules given for English bond are again applicable, the only difficulty being to obtain perfect bond between A and B. This will be overcome by remembering that the centre line drawn

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