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... Masonry Masonry Geometry and arrangement Durability and fire resistance Preliminary sizing of masonry elements Masonry design to BS 5628 Masonry design to CP111 Lintel design to BS 5977 Masonry ... agreed to the exterior or interior Buildings may be listed because of their association with an important architect, person or event or because they are a good example of design, building type, construction ... planning policy may be found in White Papers, Planning Policy Guidance Notes (PPGs), Mineral Policy Guidance Notes (MPGs), Regional Policy Guidance Notes (RPGs), departmental circulars and ministerial...

Ngày tải lên: 17/10/2012, 09:53

... Nitrogen increases strength, but it may cause aging It also raises the ductility and fracture transition temperatures Oxygen, like nitrogen, may be a cause of aging Also, oxygen decreases ductility and ... residual stresses usually causes some premature inelastic action; that is, yielding occurs in localized portions before the nominal stress reaches the yield point Because of the ductility of ... steels, cooling austenite below the A3 temperature line causes transformation of some of the austenite to ferrite (This is a pure iron, also called alpha iron, whose crystalline structure is bodycentered...

Ngày tải lên: 18/10/2012, 16:13

... accommodate tolerances Large steel buildings also move significantly as construction loads and conditions change Ambient environmental conditions also cause deflections in large structures For special ... multiple lengths Sawing is also used for relatively light columns, because the cut produced is suitable for bearing and sawing is faster and less expensive than milling Some fabricators utilize cold ... materials for controlling the shape of the weld In some cases, the coating also adds alloying elements As the arc moves along, the molten metal left behind solidifies in a homogeneous deposit, or weld...

Ngày tải lên: 18/10/2012, 16:13

... FIGURE 3.1 Vector F represents force acting on a on the bracket bracket Because of the additive properties of forces, force F may be resolved into two concurrent force components Fx and Fy in the ... not exceed a certain limit Steels also are isotropic; i.e., the elastic properties are the same in all directions The material also may be assumed homogeneous, so the smallest element of a steel ... nondeformable, since the forces acting on it cause very small deformations It is assumed that no appreciable changes in dimensions occur because of applied loading For some structures, however, such changes...

Ngày tải lên: 18/10/2012, 16:13

... line of action of load P at X (Fig 4.1) Because P and the two reactions are in equilibrium, the line of action of reaction RL at the left support also must pass through X As indicated in Fig ... Analysis, Van Nostrand Reinhold Company, New York; G L Rogers and M L Causey, Mechanics of Engineering Structures, John Wiley & Sons, Inc., New York; J Michalos, Theory of Structural Analysis and ... Ѩ␾ ␪ Ѩ␪ (4.15) N␪r␾ ϩ N␾r␪ ϩ Zr␪r␾ ϭ When the loads also are symmetrical about the shell axis, Eqs (4.15) take a simpler form and are easily solved, to yield 4.10 SECTION FOUR R R N␪ ϭ Ϫ sin ␪...

Ngày tải lên: 18/10/2012, 16:13

... Limitations also are set on maximum spacing of fasteners, for several reasons In builtup members, stitch fasteners, with restricted spacings, are used between components to ensure uniform action Also, ... deform in a controlled manner when subjected to the tightening force The specification also provides guidance on use of such devices to assure proper installation (Art 5.14) 5.4 CARBON-STEEL OR ... composite construction are a common application Welded studs also 5.6 SECTION FIVE FIGURE 5.2 A307 Grade A carbon-steel bolts; heads are also marked to identify the manufacturer or distributor (a)...

Ngày tải lên: 18/10/2012, 16:13

... 6.13 Soil Profile Descriptions for Seismic Analysis Soil Profile Type* A B C D E F Description** Hard rock with vs Ͼ 5000 ft / sec Rock with 2500 ft / sec Ͻ vs Յ 5000 ft / sec Very dense soil and soft ... Stiff soil with 600 ft / sec Յ vs Յ 1200 ft / sec or with 15 Յ N or Nch Յ 50 or 1000 psf Յ su Յ 2000 psf A soil profile with vs Ͻ 600 ft / sec or any profile with more than 10 ft of soft clay Soft ... defined as soil with PI Ͼ 20, w Ն 40%, and su Ͻ 500 psf Soils requiring site-specific evaluations: Soils vulnerable to potential failure or collapse under seismic loading such as liquefiable soils,...

Ngày tải lên: 18/10/2012, 16:13

... cost A partially composite design also may be used advantageously when the number of shear connectors required for a fully composite section cannot be provided because of limited flange width and ... two rows in each flange The number of bolts per row is more than two The web of each member is also spliced with a plate with two rows of 11⁄8-in-diameter A325 bolts The structural engineer analyzes ... Lateral load on the diagonal in this example is due to wind only and equals 65 kips The diagonals also support the steel beam at midspan As a result, the compressive force on each brace due to dead...

Ngày tải lên: 18/10/2012, 16:13

... Although there is a cost premium associated with lightweight concrete, sometimes the savings in steel framing and foundation costs can outweigh the premium Also, lightweight concrete in sufficient ... deck is available with depths of 41⁄2, 6, and 71⁄2 in from some manufacturers Cellular roof deck is sometimes used to provide a smooth soffit When a lightweight insulating concrete fill is placed ... deflections, and camber that exceeds the actual dead-load deflection can sometimes be troublesome, since it may affect the fire rating (because of insufficient concrete-fill thickness over metal deck), the...

Ngày tải lên: 18/10/2012, 16:13

... seismic zone and the soil conditions at the site In general, soft soils translate into larger seismic coefficients In seismic zone 4, CV and Ca also depend upon the seismic source type and the ... 2.0, and it depends upon the seismic source type and the distance from this source NV is always 1.0 for structures more than 15 km from the source and for source type C T is the fundamental period ... However, there have also been differences in the detailed approach used by the UBC and NEHRP provisions, and in recent years efforts have been made to resolve these differences, because of the move...

Ngày tải lên: 18/10/2012, 16:13

... (10.34) absolute value of maximum moment in the unbraced segment absolute value of moment at quarter point of unbraced segment absolute value of moment at centerline of unbraced segment absolute ... accordance with Art 10.14 Pno ϭ nominal axis strength determined in accordance with Art 10.14, with Fn ϭ Fy Mnx , Mny ϭ nominal flexural strengths about the centroidal axes determined in accordance ... not be considered because of the bracing provided by the sheathing Testing can also be used to establish the strength of assemblies Steel stud wall assemblies with sheathing also serve as in-plane...

Ngày tải lên: 18/10/2012, 16:13

... Tension-member components also may be tied together with end stay plates and lacing bars like compression members The last fastener in the stay plates preferably should also pass through the end ... Table 11.20A (a) is applicable to redundant load-path structures These provide multiple load paths so that a single fracture in a member or component cannot cause the bridge to collapse The AASHTO ... multi-load-path structures be used unless ‘‘there are compelling reasons to the contrary.’’ Also, main tension members and components whose failure may cause collapse of the bridge must be designated as FCM...

Ngày tải lên: 18/10/2012, 16:13

... loading of two axles ft apart, each axle weighing 24 kips, is usually also required and should be used if it causes higher stresses Some states prefer 30 kip axles instead of 24 kips Dead Loads Superstructure ... girders and should be used wherever feasible (See also Art 12.1.) Advantage also should be taken of continuity wherever possible, for the same reasons Spacing For stringer bridges with spans up to ... of stronger steels, because some offer maintenance benefits as well as a favorable strength-cost ratio But in small quantities, these steels may be expensive or unavailable So where only a few girders...

Ngày tải lên: 18/10/2012, 16:13

... bottom with solid plates, perforated plates, or stay plates and lacing Alternatively, they may be connected at the top with solid cover plates and at the bottom with perforated plates, or stay plates ... piers In economic comparisons, it is reasonable to assume some increased cost of steel fabrication if skewed trusses are to be used If a skewed crossing is a necessity, it is sometimes possible to ... to the nosing action of locomotives caused by unbalanced conditions in the mechanism and also forces due to the lurching movement of cars against the rails because of the play between wheels and...

Ngày tải lên: 18/10/2012, 16:13

... truss or solid rib, but the moment for variable loading conditions is divided between arch and tie, somewhat in proportion to the respective stiffnesses of these two members For this reason, for ... loading There has been some concern over the safety of tied-arch bridges because the ties can be classified as fracture-critical members A fracture-critical member is one that would cause collapse of ... expensive than solid-ribbed arches, because the trusses may be fabricated in small, lightweight sections, much more readily transported to the bridge site In the examples of Art 14.8, solid ribs...

Ngày tải lên: 18/10/2012, 16:13

Ngày tải lên: 18/10/2012, 16:13

Ngày tải lên: 07/08/2013, 23:46

Ngày tải lên: 03/12/2013, 10:48

Ngày tải lên: 24/12/2013, 06:16

Ngày tải lên: 11/07/2014, 13:49