The Principles of Structural Design, الجزء 2W. & J. Mackay & Company [for] the Royal Engineers Institute, 1898 |
عبارات ومصطلحات مألوفة
abutment angle irons angle of repose applied arch ring ascertain bending bending moments booms braced girders cables calculated cantilevers Chapter compression compressive stress concrete considered construction cosec cross girders curve dead load deflection depth diagonals distance distributed draw earth engineers extrados factor of safety feet fixed flange stress foot run formula funicular graphic Hence horizontal component horizontal thrust inch-tons investigation joint length Line of Resistance live load main girders masonry maximum method moments parabolic parallel passing loads piers plane Plate polygon position principle produced reaction represent rivets roadway rolling load shearing stress shown in Fig sloping span spandril square foot square inch stability steel stiffening girder stress intensity structure struts supported surface suspension bridge tangent tension thickness timber tons per square trestles truss trussed beam uniform load uniformly vertical voussoir W₁ weight width wire wrought iron
مقاطع مشهورة
الصفحة 276 - The assumption on which the rule is based, of an uniform rate of variation of that component of the pressure which is normal to the pressed surface, is known to be sensibly correct in the case of beams, and is probably very near the truth in walls of uniform or nearly uniform thickness. Whether, or to what extent, it deviates from exactness in walls of varying thickness, is uncertain in the present state of our experimental knowledge.
الصفحة 251 - The properties of earth with respect to adhesion and friction are so variable that the engineer should never trust to tables or to information obtained from books to guide him in designing earthworks, when he has it in his power to obtain the necessary data either by observation of existing earthworks in the same stratum or by experiment.
الصفحة 224 - If the forces which balance each other in or upon a given body or structure be distinguished into two systems, called respectively active and passive, which stand to each other in the relation of cause and effect, then urill the passive forces be tlte least which are capable of balancing the active forces, consistently with the physical condition of the body or structure.
الصفحة 276 - ... is not the whole pressure, but only its vertical component ; and the whole pressure exceeds the vertical pressure in a ratio which becomes the greater the greater the " batter," or deviation of the face from the vertical.
الصفحة 292 - ... of the dam may be reduced below what is termed the gravity section, meaning thereby a crosssection or profile of such proportions that it is able, by the force of gravity alone, to resist the forces tending to overturn it or to slide it on its base at any point. (2) That a gravity...
الصفحة 292 - ... able, by the force of gravity alone, to resist the forces tending to overturn it, or to slide it on its base at any point. "2. That a gravity dam, built in plan on a curve of long radius, derives no appreciable aid from arch action so long as the masonry remains intact ; but that, in case of a yielding of the masonry, the curved form might prove of advantage. " The division between what may be called a long radius and what may be called a short radius is of course indefinite, and depends somewhat...
الصفحة 162 - ... required. In each case four feet in length have been allowed for bearings at the ends of the span. The enormous difference would not exist if the beam and wire had only to carry the man, although even then there would be a great difference in favour of the wire ; the main difference arises from the fact that the bridge has to carry its own weight. The chief merit of the suspension bridge does not, therefore, come into play until the 'weight of the rope or beam is considerable when compared with...
الصفحة 236 - That thrust may bo roughly computed by multiplying the travelling load per lineal foot by the radius of curvature of the intrados at its crown in feet.
الصفحة 296 - ... approximately. A second approximation to b may be easily made if required, as W is the only variable on the right of the equation for any given value of h at which the breadth b is being computed. Having found b, the next step is to ascertain how much of it must lie under the inner face of the dam, ie within the vertical through the crest, in order to bring the incidence of the resultant weight of the whole superincumbent mass of b masonry and water to the distance - from the inner toe.
الصفحة 223 - In which the centers of resistance of joints fall beyond the middle third of the depth of the arch ring ; but the stability of such arches is either now precarious, or must have been precarious while the mortar was fresh.