Bracing

“ Old structures are very frequently deficient in bracing, which may, in such cases, be advantageously introduced; or girders individually weak may be rendered collectively efficient by suitable bracing. ”

“ In buildings of small width in proportion to their height this method of securing rigidity is generally found to be inadequate, and the frame is also braced at right angles to the outer walls to take up the strains directly. In each case all strains are carefully computed. The bracing is accomplished by the introduction at the angles of the columns and girders or beams of gusset plates or knee braces, or by diagonal straps or rods properly attached by rivet or pin connexions. ”

“ But most braces, you may not be aware, slip down unpleasantly on the shoulder-blade, and so lead to an awkward habit of hitching them up by the sleeve-hole of the waistcoat at frequent intervals. Such a habit must be felt to be ungraceful. ”

“ Old braces were braces, these are mere sources of weakness, they do not brace; when weight is applied to the seat the tendency is to drive the legs apart, then out falls the brace. No mortice holds it, it has no function to fulfil. In the old chair how firm all the joints are made! Stout oak pegs are driven through [70] every mortice, and every precaution is taken to prevent gaping at the joints, to resist strain put on them. ”

“ In a steel structure, a can very easily be made a tension member by anchoring its lower end to a heavy [Pg 35] foundation. This resists the tendency to overturn and makes a very stable structure. In practice, braces can generally be located parallel to the line of resultant strain, Fig. 29, or outside this line, as shown in Fig. 30, so that the strain due to the pull of the rope will come mainly on the inclined brace and not on the upright. ”

“ If we wish to lay out a brace having a three-foot run on both post and beam, the matter is quite simple, for we can take 12 inches on the tongue and 12 inches on the blade and transfer this distance three times on a straight line and we have the extreme length of the brace from point to point, and by marking along the blade at one end of this length and along the tongue at the other end we also get the bevels. ”

“ In cutting braces always allow in length from a sixteenth to an eighth of an inch more than the exact measurement calls for.
Directly under the half-inch marks on the outer edge of the back of the tongue will be noticed two figures, one above the other. These represent the run of the brace, or the length of two sides of a right-angled triangle; the 62 figures immediately to the right represent the length of the brace or the hypothenuse. For instance, the figures 36-36 59-91 show that the run on the post and beam is 36 inches, and the length of the brace is 50.91 inches. ”

“ Braces and trusses are something like rafters and when the run is known, there should be no difficulty in getting the lengths and proper bevels.
In the first place it is always best to make a pattern and then mark out the timber work from the pattern. Suppose we want braces having a “four-foot run”—that is, the brace is to form a diagonal from points four feet from the post and four feet from the girt. Take a piece of stuff already prepared, six feet long, four 109 inches wide and half-inch thick, gauge it three-eighths from jointed edge. ”

“ Fig. 13.—Outside Braces. In the village of Naruge, in Yamato, I noticed in an old inn a diagonal brace which made a pleasing ornamental feature to a solid frame-work, upon which rested a ponderous supplementary roof, heavily tiled. As the horizontal beams were supported by uprights beyond the ends of the brackets, no additional strength was gained by these braces in question, except as they might prevent fore and aft displacement. ”

“ Straining pieces are secured to the upper and lower faces of the shore to serve as abutments for the ends of the braces. The best angle for these braces is one of 45°, but a smaller inclination than this is frequently adopted. Wedges are inserted, usually at the end of the flyer so as to tighten this up between the wall-plates, and sometimes between the braces and the straining piece, and carefully driven to tighten up the whole and cause each timber to find a close bearing. ”

“ But the limb they carry is heavy, so they rapidly become overstretched and it is difficult to keep them properly adjusted.
b. The stretching is naturally diminished if the upper part of the brace is not elastic but an elastic section is inserted in its lower third, in front and behind.
c. But the patients almost always say that better command of the limb is obtained with inelastic braces. If the strap is wide on the shoulder, the pressure is well borne, and the lower attachment may be made narrower, consisting of a leather thong (Fig. 64) . ”

“ BRACE. The braces are ropes belonging to all the yards of a ship; two to each yard, rove through blocks that are stropped to the yards, or fastened to pendants, seized to the yard-arms. Their use is either to square or traverse the yards horizontally; hence, to brace the yard, is to bring it to either side by means of the braces. In ship-building, braces are plates of iron, copper, or mixed metal, which are used to bind efficiently a weakness in a vessel; as also to receive the pintles by which the rudder is hung. ”

“ He was caught in a reclining posture, his back firmly supported by a solid beam. Another lay across his breast, but he had been able to shrink a little away from it so that it no longer oppressed him, though it was immovable. A brace joining it at an angle had wedged him against a pile of boards on his left, fastening the arm on that side. His legs, slightly parted and straight along the ground, were covered upward to the knees with a mass of debris which towered above his narrow horizon. His head was as rigidly fixed as in a vise; he could move his eyes, his chin—no more. ”

“ A housed brace joint is a joint in which the brace is housed into the rectangular members except that the outer end of the mortise is cut at right angles and the inner end diagonally to receive the brace which is cut to correspond. ”

“ The cutaneus brachii superior is a small nerve which springs from the last brachial plexus root and passes between the skin and the triceps brachii muscle on the dorsal surface of the upper arm, or brachial, region. It extends down over the elbow region, where it gives off numerous branches to the skin of these regions, to the meta-patagium and to the extensor muscles of the upper arm. ”

“ Even with that precaution, the string very often bruises the arm, and ladies sometimes have the bracer wadded, or lined with India rubber to make it more elastic, and thus to diminish the force of the rebound. ”

“ Inasmuch as the ribs, at their tops, are confined by a tape to a circumference corresponding with the size of the waist, it is reasonably clear that, if they were expanded to their utmost tension at the hip portion, a single set of braces would afford but slight resistance to contraction. ”

“ In a shoulder brace, a back support comprising a plurality of non-elastic back stays symmetrically spaced on either side of the medial line thereof flaring upwardly and separating at the top to embrace the shoul- der blades, with straps secured across the upper end of said stays to brace and hold the same in position, and straps secured to the upper corners of the back support and adapted to pass from the rear forwardly over the shoulders and thence rearwardly under the armpits and thence to the front of the waist, with a loose sliding attachment for the passing under blades the straps. ”

“ For the back stroke therefore, and that the arm may not only bend at the elbow, but also extend and straighten itself with force, other muscles, the longus, and brevis brachiæus externus, and the aconæus, placed on the hinder part of the arms, by their contractile twitch, fetch back the fore-arm into a straight line with the cubit, with no less force than that with which it was bent out. The same thing obtains in all the limbs, and in every moveable part of the body. ”

“ It can thus very well happen that the upper or the middle braces may receive more stress in the end, than the lower braces. In fact, this was asserted to be generally true, for well-drained material, by many engineers in the valuable discussion on Mr. Meem’s paper referred to. Other engineers advised caution in accepting this view, and asserted that in wet or saturated ground the lower braces were most severely stressed. ”

“ One wooden brace and two iron braces are to be put in, as shown upon the plan hereto annexed. The wooden brace is to be of one piece, or of two pieces well bolted together, of selected lumber, free from knots and other imperfections, squared, and measuring 6 by 8 inches in 337 cross section. The iron braces are to be of 1 inch diameter, best quality wrought-iron rods. The bearing plates, four to each rod, are to be not less than 10 inches in diameter, of sufficient strength, and securely and permanently fastened to the braces. ”

“ The perfect fit thus secured suffices, in simple fracture, to keep the parts in close apposition; while the movements of eating and speaking are very little interfered with.
Fig. 25.—Showing the method for supporting externally the jaws in the splint, when the teeth are not fastened to it by screws, E. Upper wing; G. Lower wing; H. Mental band to keep the jaw up in the splint; I. Neck-strap to keep the band back; K. Balance-strap to hold skull-cap in place. The upper wings are of course dispensed with, when a single splint only is used. ”

“ The angle braces are made 1/2" × 1/2" × 11" and cross each other with a halved joint, as shown. The ends are cut at an angle to conform to the slope of the uprights and are attached to them by 1" brads and glue.
Piece E is now made, 1-1/4" × 1-1/4" × 2", and is tapered to 3/4" square at the upper end. This is done by measuring in 1/4" from each upper corner and drawing to the lower corners and cutting to the line. A small hole is bored in the center of the upper end to start the screw which holds piece B in place.
[Pg 81] ”

“ The course of the brachial artery along the inner border of the biceps muscle is comparatively superficial, from the point where it leaves the axilla to the bend of the elbow. In the whole of this course it is covered by the fascia of the arm, which serves to isolate it from the superficial basilic vein, B, and the internal cutaneous nerve, both of which nevertheless overlie the artery. The median nerve, d, Plate 15, accompanies the artery in its proper sheath, which is a duplication of the common fascia ”

“ Fig. 75 shows the brace in position, the dotted lines show where the square was placed on the pattern. It is well to thoroughly understand the method of obtaining the lengths and bevels of irregular braces. A little study will soon enable any person to make all kinds of braces. ”

“ The tighter the lace is drawn the more powerful will be the extending force.
Instead of attaching the extension brace to the leg piece it may be made to pass under a pulley in the interior of the knee. What actually happens is that the thigh piece drops, owing to its weight, when the limb is swung free; this throws a strain on the brace which is transmitted to the leg piece by the following mechanism. ”

“ They spent some time screwing on more of the right-angle braces, for though they lacked many of the fittings usually recommended for such work, they had an abundance of these braces. They served very well to hold all corners firmly and rigidly together, although of course absolute rigidity of such open framing could only be secured by a thorough system of taut wire trussing. ”

“ The theory of the invention is that, as the collar at the bottom of the standard is raised, the braces will force the ribs to expand to the circumference limited by the tape or elastic affixed to the lower extremities of the ribs. Should the collar be pushed above the mean center of expansion, which is attained when the braces are at right angles with the standard, the tendency to expand would cease, and contraction would begin. ”

“ The Brachial Plexus.—Lesions of the brachial plexus may be divided into those above the clavicle and those below that bone.
In the supra-clavicular injuries, the violence applied to the head or shoulder causes over-stretching of the anterior branches (primary divisions) of the cervical nerves, the fifth, or the fifth and sixth being those most liable to suffer. Sometimes the traction is exerted upon the plexus from below, as when a man in falling from a height endeavours to save himself by clutching at some projection, and the lesion then mainly affects the first dorsal nerve. ”

“ The grooves in these arms are so formed as to command the braces, and to contain a quantity of Parker’s or Roman cement, by which the bolts are preserved from the effects of oxidation. These collars and arms, with their connecting malleable iron-bars, form a girth immediately above the diagonal struts or braces B B B, Fig. 5. A similar chain of connection is in like manner formed below the junction of these diagonal struts, with the main tubes, which, like those described above, has the effect of binding the whole fabric horizontally. ”

“ To take a common example,—in fracture close to the wrist joint, it is necessary to arrange the splint so that the patient can move his fingers and thumb, and the splint must be taken off every day, in order that the wrist and fingers may be gently bent, straightened and exercised. ”