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Ngày tải lên: 05/09/2013, 11:02

Ngày tải lên: 22/01/2014, 10:20

Ngày tải lên: 27/03/2014, 02:23

... 2SC4891-SAN 2SC5294-MAT Transistor au Silicium NPN TRANSISTOR 2SC5296-SAN Transistor au Silicium NPN+Diode 1500V 8A 60W 2SC5297-SAN Transistor au Silicium NPN 1500V 8A 60W 2SC5299-SAN Transistor au ... 2SC3831-SKN Transistor au Silicium NPN 500V 10A 100W 2SC3833-SKN Transistor au Silicium NPN 500/400V 12A 100W 2SC3842-FUJ Transistor au Silicium NPN 600V 10A 70W 32MHZ 2SC3844-FUJ Transistor ... 2SC3886A Transistor au Silicium NPN 1500V 8A 50W 0.1us 2SC3886A/DIV Transistor au Silicium NPN 1500V 8A 50W 0.1US 2SC388A-MBR Transistor au Silicium NPN 25V 50mA 0.3W 300MHz 2SC3890-SKN Transistor...

Ngày tải lên: 12/10/2012, 15:30

... large amount of strain hardening. The strain at which strain hardening begins ( ⑀ st ) and the rate at which stress increases with strain in the strain-hardening range (the strain-hardening modulus ... stress-strain curve. Also, the value of true strain at fracture is much greater than the engineering strain at fracture (though until yielding begins true strain is less than engineering strain). 1.8 ... members causes, in adjacent restrained metal, strains that can exceed the yield-point strain. In thick material, triaxial stresses may develop because there is restraint in the thickness direction...

Ngày tải lên: 18/10/2012, 16:13

... abutting cross-sectional configurations is made unless specifically required by the contract documents. The as-fabricated straightness toler- ances of members are one-half of the standard camber and sweep ... are pulled into plumb. It is necessary, therefore, to erect from the more restrained portion of the framing to the less restrained. If a structure has a braced center core, that area will be erected first ... welding may be direct or alternating current. With direct current, either straight or reverse polarity may be used. For straight polarity, the base metal is the positive pole and the electrode is...

Ngày tải lên: 18/10/2012, 16:13

... strain in the x direction is accompanied by lateral strains of opposite sign. If ⑀ x is a tensile strain, for example, the lateral strains in the y and z directions are contractions. These strains ... top. The plane where the strain is zero is called the neutral axis. Below the neutral axis, tensile strains act, increasing in magnitude downward. With use of the stress-strain relationship of the ... distance y from the neutral axis b(y) ϭ width of beam at distance y from the neutral axis ƒ(y) ϭ normal stress at a distance y from the neutral axis c b ϭ distance from neutral axis to beam bottom c t ϭ distance...

Ngày tải lên: 18/10/2012, 16:13

... roof decking to distribute loads transversely to the chords (Fig. 4.26b). A folded-plate structure has a two-way action in transmitting loads to its supports. In the transverse direction, the plates ... eliminates the need for such equations. Figure 4.27a shows a transverse section through part of a folded-plate structure. An interior element, plate 2, transmits the vertical loading on it to joints 1 and ... resisting only tension, it is limited to transferring forces only along its length. The vast majority of structures require a more complex ability to transfer forces. Thus it is logical to combine...

Ngày tải lên: 18/10/2012, 16:13

... and axial transfer force. The transfer force, sometimes called ‘‘drag’’ or ‘‘drag through’’ force, is the axial force that must be transferred to the opposite side of the column. The transfer ... section are prohibited. Groove welds also are classified as complete-penetration and partial-penetration welds. In a complete-penetration weld, the weld material and the base metal are fused through- out ... CONNECTIONS 5.33 welds. The transverse spacing of longitudinal fillet welds in end connections should not exceed 8 in unless the design otherwise prevents excessive transverse bending in the con- nections. 5.20...

Ngày tải lên: 18/10/2012, 16:13

... neutral axis, and (2) secondary moments produced in a member of a rigid frame due to sidesway of the frame that creates eccentricity ⌬ of the axial compression load with respect to the neutral ... Stability Research Council for use with six idealized conditions of rotation and translation at column supports are illustrated in Fig. 6.4 (see also Arts. 7.4 and 7.9). The axially compression strength ... materials handling systems S ϭ roof snow load R ϭ rain load W ϭ wind load E ϭ earthquake load T ϭ restraint loads Instead of the factors 0.75 and 0.66, allowable stresses may be increased one-third...

Ngày tải lên: 18/10/2012, 16:13

... a concentrated load occurs on a beam, the number of shear connectors between the concentrated load and the inflection point should be adequate to develop the maximum moment at the concentrated ... or by longitudinal welds in combination with transverse welds: A ϭ A g 2 ϭ gross area of member, in (c) When the tension load is transmitted only by transverse welds: 2 A ϭ area of directly connected ... of loading, in (a) When the tension load is transmitted only by bolts or rivets: A ϭ A n 2 ϭ net area of the member, in (b) When the tension load is transmitted only by longitudinal welds to other...

Ngày tải lên: 18/10/2012, 16:13

... bending stresses. Lateral loads in the transverse direction are transferred to the truss top chords via dia- phragm action of the floor deck. These loads are transmitted through the depth of the ... trusses to the bottom chords and are then transferred through the floor deck at that level to the adjacent-truss top chords. The overturning couple produced by the transfer of lateral load from the top ... ends of the truss. Only axial forces are induced in the exterior columns. Therefore, transverse lateral loads are transmitted down through the structure without creating bending stresses in the trusses...

Ngày tải lên: 18/10/2012, 16:13

... more common in buildings where the lateral resistance was concentrated in limited portions of the structure, since this concentration produces larger member sizes. The redundancy factor described ... ƒ j (t) for each mode of vibration. Figure 9.7 shows the design response spectra recommended by the UBC unless site-specific spectra are employed. The response is based on calculations of the single-degree-of-freedom ... concentrate the inelastic deformation (ductility demand) into a small portion of the structure. This can dramatically increase the ductility demand for that portion of the structure. This concentration...

Ngày tải lên: 18/10/2012, 16:13

... fused area at plane of maximum shear transfer ϭ 0.7d Ϫ 1.5t but Յ 0.55d t ϭ total base steel thickness of sheets involved in shear transfer See Fig. 10.9 for illustration of diameters d, d a , and ... fully effective. To do this, first determine the location of the neutral axis. Because the top flange is not fully effective, the neutral axis will be located below the centroidal axis of the gross ... weld t e ϭ effective throat dimension 10.17.2 Fillet Welds Fillet welds are considered to transmit longitudinal and transverse loads with shear stresses. For these welds, the nominal strength is the...

Ngày tải lên: 18/10/2012, 16:13

... for Highway Bridges,’’ American Association of State Highway and Transportation Officials. 100 psf transverse 40 psf longitudinal Transverse and longitudinal loads should be applied simultaneously. Wind ... BRIDGES 11.9 represents forces from an automobile or pickup as in PL-2, in addition to a 50,000-lb van- type tractor-trailer traveling at 50 mph and impacting at an angle of 15 Њ . The performance criteria require ... penetrate or hurdle the railing, must remain upright during and after the collision. and be smoothly redirected by the railing. Thus, a rail system that can withstand the impact of a tractor-trailer...

Ngày tải lên: 18/10/2012, 16:13

... computations of neutral-axis location and section moduli for the composite section are tabulated in Table 12.2. To locate the neutral axis, moments are taken about the neutral axis of the rolled ... for the location of the neutral axis and for the section moduli S st and S sb of the trial plate-girder section are tabulated in Table 12.17. For unsymmetrical girders with transverse stiffeners but ... effects of creep. The computations of neutral-axis location and section moduli for the composite section are tabulated in Table 12.8. To locate the neutral axis, moments are taken about middepth...

Ngày tải lên: 18/10/2012, 16:13

... Reinforced concrete decks may be transverse, longitudinal or four-way slabs. ã Transverse slabs are supported on stringers spaced close enough so that all the bending in the slabs is in a transverse direction. ã Longitudinal ... with a concentrated load at top-chord level and rigid connection to a floorbeam. This system offers elastic restraint to buckling of the top chord. The analysis of elastically restrained compression ... should be made to determine the best position for the trusses. Train weight on a bridge on a curve is not centered on the centerline of track. Loads are greater on the outer truss than on the inner...

Ngày tải lên: 18/10/2012, 16:13

... panels at 27.8 ft SPAN: 778 ft RISE: 151 ft RISE / SPAN ϭ 1:5.2 NO. OF LANES OF TRAFFIC: 4, including 2 street-railway tracks HINGES: Two CROWN DEPTH: 25 DEPTH/ SPAN ϭ 1:31 AVERAGE DEAD LOAD: LB ... Washington Department of Transportation ENGINEER: Bridges and Structures Division, Washington DOT FABRICATOR: Northwest Steel Fabricators, Vancouver, Wash. GENERAL CONTRACTOR: Dale M. Madden, ... solid-ribbed arch, 15 panels at 50 ft SPAN: 750 ft RISE: 124.4 ft RISE / SPAN ϭ 1:6 NO. OF LANES OF TRAFFIC: 6 plus 10-ft berms HINGES: 0 CROWN DEPTH: 4 ft DEPTH / SPAN ϭ 1:187 AVERAGE DEAD LOAD:...

Ngày tải lên: 18/10/2012, 16:13

Ngày tải lên: 18/10/2012, 16:13

Ngày tải lên: 25/10/2012, 09:50