Wednesday, March 19, 2008

-- G L O S S A R Y --

BEARING:
In a bolted connection, limit state of shear forces transmitted by the bolt to the connection elements.

BEARING TYPE CONNECTION:
Bolted connections where shear forces are transmitted by the bolt bearing against the connection element.

BRACED FRAMES:
An essential vertical truss system that provides resistance to lateral forces and provides stability to the structural system

BUCKLING:
Limit state of sudden change in the geometry of the structure or any of its elements under a critical loading condition.

BUCKLING STRENGTH:
Nominal strength for buckling or instability limit states

CAMBER:
Curvature fabricated into a beam or truss so as to compensate to deflection included by loads.

CLADDING:
Exterior cover of structure

COLD FORMED STEEL STRUCTURAL MEMBER:
Shape manufactured by press-braking blanks sheared from sheets, cut lengths of coils or plates, or by roll forming cold- or hot-rolled coils or sheets; both forming operations being performed at ambient room temperature, that is, without manifest addition of heat such as would be required for hot forming.

COMPLETE JOINT PENETRATION GROOVE WELD (CJP):
Groove weld in which weld metal extends through the joint thickness, except as permitted for HSS connections

COPE:
Cutout made in a structural member to remove a flange and conform to the shape of the intersecting member.

DOUBLER:
Plate added to, and parallel with, a beam or column web to increase resistance to concentrated forces.

DRIFT:
Lateral Deflection of Structures

END RETURN:
Length of the fillet weld that continues around a corner in the same plane

FASTENER:
Generic term for bolts, rivets or other connecting devices

FATIQUE:
Limit state of crack initiation and growth resulting from repeated application of live loads.

FAYING SURFACE:
Contact surface of connection elements transmitting a shear force.

FILLER METAL:
Metal or allow to be added in making a welded joint.

FILLER:
Plate used to build up the thickness of one component.

FLEXURAL BUCKLING:
Buckling mode in which a compression member deflects laterally without twist or change in cross-section shape.

FLEXURAL – TORTIONAL BUCKLING:
Buckling mode in which a compression member bends and twists simultaneously without change in cross sectional shape.

FORCE:
Resultant of distribution of stress over a prescribed area

FULLY RESTRAINED MOMENT CONNECTION:
Connection capable of transferring moment with negligible rotation between connection members

GIRDER FILLER:
Narrow piece of sheet steel used as a fill between the edge of a deck sheet and the flange of a girder in a composite floor system constructed using a formed steel deck.

GIRT:
Horizontal structural member that supports wall panels and is primarily subjected to bending under horizontal loads, such as wind load

GOUGE:
Relatively smooth surface groove or cavity resulting from plastic deformation or removal of material.

GRIP:
Thickness of material through which a bolt passes

LACING:
Plate, Angle or other steel shape in a lattice configuration, that connects two steel shapes together

LOCAL BENDING:
Limit state of large deformation of a flange under a concentrated tensile force.

LOCAL BUCKLING:
Limit state of buckling of a compression element within a cross section.

LOCAL CRIPPLING:
Limit state of local failure of web plate in the immediate vicinity of a concentrated load or reaction.

LOCAL YIELDING:
Yielding that occurs in a local area of an element.

MILL SCALE:
Oxide surface coating on steel formed by the hot rolling process

MILLED SURFACE:
Surface that has been machined flat by a mechanically guided tool to a flat, smooth condition.

MOMENT CONNECTION:
Connection that transmits bending moment between connected members.

MOMENT FRAME:
Framing system that provides resistance to lateral loads and provides stability to the structural system, primarily by shear and flexure of the framing members and their connection

NOMINAL DIMENSIONS:
Designated or Theoretical dimension, as in the tables of section properties

NONDESTRUCTIVE TESTING:
Inspection procedure wherein no material is destroyed and integrity of the material or component is not affected

OUT OF PLANE BUCKLING:
Limit state of a beam-column bent about its major axis while lateral buckling or lateral Torsional buckling is not prevented by lateral bracing.

PARTIALLY RESTRAINED MOMENT CONNECTION:
Connection Capable Of Transferring Moment With Rotation Between Connected Members That Is Not Negligible.

PERMANENT LOAD:
Loads in which variations over time are rare or of small magnitude are permanent load. All other loads are variable loads.

POST-BUCKLING STRENGTH:
Load or force that can be carried by an element, member or frame after intial buckling has occurred.

PRE-TENSIONED JOINT:
Joint with high-strength bolts tightened to a specified minimum pretension.

REENTRANT:
In a cope or weld access hole, a cut at an abrupt change in direction in which the exposed surface is concave.

ROOT OF JOINT:
Portion of a joint t be welded where the members are closest to each other.

SAFETY FACTOR:
Factors that accounts for deviations of the actual strength from the nominal strength, deviations of the actual load from the nominal load, uncertainties in the analysis that transforms the load into a load effect, and for the manner and consequences of failure.

SHEAR BUCKLING:
Buckling mode in which a plate element, such as the web of a beam, deforms under pure shear applied in the plane of the plate.

SHIM:
Thin layer of material used to fill a space between faying or bearing surfaces.

SIMPLE CONNECTION:
Connection that transmits negligible bending moment between connected members.

SLIP:
In a bolted connection, limit state of relative motion of connected parts prior to the attainment of the available strength of the connection.

SLIP CRITICAL CONNECTION:
Bolted connection designed to resist movement by friction on the faying surface of the connection under the clamping forces of the bolts.

SNUG TIGHTENED JOINT:
Joint with the connected plies in firm contact

SPLICE:
Connection between two structural elements joined at their ends to form a single longer element.

STABILITY:
Condition reached in the loading of a structural component, frame or structure in which a slight disturbance in the loads or geometry does not produce large displacement.

STIFFENER:
Structural element, usually an angle or plate, attached to a member to distribute load, transfer shear or prevent buckling.

STRESS:
Force per unit area caused by axial force, moment, shear or torsion.

THERMALLY CUT:
Cut With Gas, Plasma or LASER

TRANSVERSE STIFFENER:
Web stiffener oriented perpendicular to the flanges, attached to the web.

TURN OF NUT MEATHOD:
Procedure whereby the specified pretension in high strength bolts is controlled by rotating the fastener component a predetermined amount after the bolt has been snug tightened.

UNFRAMED END:
The end of a member not restrained against rotation by stiffener or connection elements.

WEATHERING STEEL:
High strength, low-alloy steel that, with suitable precautions, can be used in normal atmospheric exposures (not marine) without protective paint coating

WEB BUCKLING:
Limit state of lateral instability of a web.

WEB COMPRESSION BUCKLING:
Limit state of out-of-plane compression buckling of the web due to a concentrated compression force.

WEB SIDEWAY BUCKLING:
Limit state of lateral buckling of the tension flange opposite to the location of a concentrated compression force.

WELD METAL:
Portion of a fusion weld that has been completely melted during welding, Weld metal has elements of filler and base metal melted in the weld thermal cycle.

YIELDING:
Limit state of inelastic deformation that occurs after the yield stress is reached.

BIAXIAL BENDING:
Simultaneous bending of a member about two perpendicular axes

BRITTLE FRACTURE:
Abrupt cleavage with little or no prior ductile deformation

CYCLIC LOAD:
Repeatedly applied external load that may subject the structure to fatigue

FATIGUE THRESHOLD:
Stress range at which fatigue cracking will not initiate regardless of the number of cycles of loading.

FLEXIBLE CONNECTION:
Connection permitting a portion, but not all, of the simple beam rotation of a member end

UNDERCUT:
Notch resulting from the melting and removal of base metal at the edge of a weld

COATED FAYING SURFACE:
A faying surface that has been primed and painted or protected against corrosion, except by hot-dip galvanizing

ENGNEER OF RECORD:
The party responsible for the design of the structure and for the approvals that are required in this specification

FAYING SURFACE:
The plane of contact between two plies of a joint

SNUG TIGHTENED JOINT:
A joint in which the bolts have been installed in accordance with section 8.1.. The snug tightened condition is the tightness that is attained with a few impacts of an impact wrench or the full effort of an iron worker using an ordinary spud wrench to bring the plies into firm contact.

BENDING MOMENT:
The internal load generated within a bending element whenever a pure moment is reacted, or a shear load is transferred by beam action from the point of application to distant points of reaction (or) The algebraic sum of all the moments of forces acting on one side of a section through a beam

AXIAL FORCE:
A system of internal forces whose resultant is a force acting along the longitudinal axis of a structural member or assembly.

LOADS

DEAD LOADS:
Dead
loads are weights of material, equipment or components that are relatively constant throughout the structure's life. Permanent loads are a wider category which includes dead loads but also includes forces set up by irreversible changes in a structure's constraints - for example, loads due to settlement, the secondary effects of prestress due to shrinkage and creep in concrete.

LIVE LOADS:
Live loads are temporary, of short duration, or moving. Examples include snow, wind, earthquake, traffic, movements, water pressures in tanks, and occupancy loads. For certain specialized structures, vibro-acoustic loads may be considered.

STATIC LOAD:
These are loads that build up gradually over time, or with negligible dynamic effects. Since structural analysis for static loads is much simpler than for dynamic loads, design codes usually specify statically-equivalent loads for dynamic loads caused by wind, traffic or earthquake.

DYNAMIC LOAD:
These are loads that display significant dynamic effects. Examples include impact loads, waves, wind gusts and strong earthquakes. Because of the complexity of analysis, dynamic loads are normally treated using statically equivalent loads for routine design of common structures.

GLOSSARY

STRUCTURAL SYSTEM:
An assemblage of load carrying components that are joined together to provide interaction or interdependence

BEAM:
Structural member that has a primary function of resisting bending moments

BEAM-COLUMN:
Structural member that resists both axial force and bending moments

COLUMN:
Structural member that has a primary function of resisting AXIAL FORCE.

DIAGONAL BRACING:
Inclined structural member carrying primarily axial force in a braced frame

PLATE GIRDER:
Built up beam

PURLIN:
Horizontal structural member that supports roof deck and is primarily subjected to bending under vertical loads such as snow, wind or dead loads

VERTICAL BRACING FRAME:
System of shear walls, braced frames or both, extending through one or more floor of a building


PLATE

BATTEN PLATE:

Plate rigidly connected to two parallel components of a built-up column or beam designed to transmit shear between the components.

TIE PLATE:
Plate element used to join two parallel components of a built up columns, girder or strut rigidly connected to the parallel components and designed to transmit shear between them.

ASD (ALLOWABLE STRENGTH DESIGN):

Method of proportioning structural components such that the allowable strength equals or exceeds the required strength of the component under the action of the ASD load combination

HOT DIP GALVANISING

In hot dip galvanising, ferrous metals or alloys, particularly cast iron and mild steel, are treated to prevent corrosion. The hot dip galvanising process involves dipping a ferrous metal article having a surface which is chemically clean, into molten zinc, which may contain minor quantities of other elements, in order to coat the surface of the article with a protective layer of zinc. The coating formed adheres as a result of alloying taking place at the ferrous metal-zinc interface. As alloying cannot take place unless the surface of the article being coated is chemically clean, the cleaning cycle is an extremely important part of the hot dip galvanising process.

Normally the initial steps in the cleaning cycle can include degreasing, for example using trichloroethylene vapour or aqueous alkaline solutions, and possibly shot or grit blasting. Acid pickling then follows and the final stage is usually flux treatment using a salt or a mixture of salts. As the fluxing treatment usually immediately precedes galvanising it is this step which most ensures wetting of the surface being coated by the molten zinc.

Initially in the hot dip galvanising process the fluxing material was provided by iron salts which remained on the ferrous metal surface after pickling. The more recent process, of which there are two main types, employ a separate fluxing agent, and differ from each other in the manner in which the fluxing agent is applied. In the "Wet Process" the ferrous metal article is pickled, sometimes rinsed, and then dipped into molten zinc through a layer of molten flux floating on the surface of the zinc. In the "Dry Process" a layer of flux is applied to the surface of the ferrous metal article to be galvanised before the article is dipped into molten zinc. Application is by applying a solution of fluxing agent to the surface and drying the article to leave the flux coating on the surface. The wet and dry processes may be used together, i.e. first a flux is dried on to the surface of the article and then the article is dipped into the molten zinc bath through a layer of molten flux.

Fluxing agents commonly used in hot dip galvanising processes are ammonium chloride, zinc chloride, physical mixtures of the two, and also a chemical combination in the form of zinc ammonium chloride. These fluxing agents may be mixed with one or more alkali metal chlorides.

Most known fluxing agents suffer from the disadvantage that they evolve copious obnoxious fume, and although the addition of alkali metal chlorides reduces the quantity of fume evolved such practice may also result in a reduction of flux efficiency.

Due to the introduction of more and more stringent environmental regulations and since hot dip galvanising is in general likely to be carried out at higher temperatures than formerly, with the probable replacement of the usual metal galvanising baths by refractory lined baths, the use of fluxes which give rise to little or no fume is becoming increasingly important.

It has now been found that hot dip galvanising by the wet process may be carried out with little fume evolution using a flux containing essentially magnesium chloride together with sodium chloride and/or potassium chloride, and optionally calcium chloride.

According to the present invention there is provided a method of hot dip galvanising a ferrous metal article which comprises passing the article into molten zinc through a molten flux disposed on the surface of the zinc, and subsequently removing the article from the molten zinc, said flux melting below 500°C and comprising 30 - 70% by weight magnesium chloride, and 20 - 70% by weight sodium chloride and/or potassium chloride. Preferably the flux melts below 460°C. The flux may also contain up to 20% calcium chloride.

Other chlorides may be present, for example, aluminium chloride, lead chloride, zinc chloride, ammonium chloride, and zinc ammonium chloride, either used alone or in combination. However, since these chlorides tend to increase the amount of fume evolved they should not constitute more than 20% by weight of the total composition.

The preferred magnesium chloride content (as MgCl 2 ) is 40 - 60% by weight, the preferred sodium and/or potassium chloride content is 30 - 60% by weight, and the preferred calcium chloride content is 0 - 10% by weight.

The flux compositions may also contain frothing agents, which are often desirable in the wet process of hot dip galvanising for increasing the thickness of the layer of flux floating on the surface of the molten zinc. Materials which slowly decompose at the temperature of the hot dip galvanising bath are suitable as frothing agents. Examples include tallow, sawdust, glycerin and various resins.

Using the flux compositions of the invention hot dip galvanising may be carried out with little fume evolution over a wide range of operating temperatures.

STRUCTURAL STEEL ABBREVIATIONS

ABBREVIATIONS
SI NO ABBREVIATION ................DEFINITION...............
1 AISC AMERICAN INSTITUTE OF STEEL CONSTRUCTION
2 ANSI AMERICAN NATIONAL STANDARD INSTITUTE
3 ASD ALLOWABLE STRESS / STRENGTH DESIGN
4 AISE ASSOCIATION OF IRON AND STEEL ENGINEERS
5 ASCE AMERICAN SOCIETY OF CIVIL ENGINEERS
6 ASME AMERICAN SOCIETY OF MECHANICAL ENGINEERS
7 ASTM AMERICAN SOCIETY OF TESTING AND MATERAIL
8 ATLSS ADVANCED TECHNOLOGY OF LARGE STRUCTURAL SYSTEMS
9 AESS ARCHITECTURALLY EXPOSED STRUCTURAL STEEL
10 AWS AMERICAN WELDING SOCIETY
11 AGS AMERICAN GALVANIZERS SOCIETY
12 CFR CODE OF FEDERAL REGULATION for the construction industry
13 CISC CANADIAN INSTITUTE OF STEEL CONSTRUCTION
14 CMAA CRANE MANUFACTURERS ASSOCIATION OF AMERICA
15 CMTR CERTIFIED MILL TEST RECORD
16 LRFD LOAD AND RESISTANCE FACTOR DESIGN
17 MBMA METAL BUILDING MANUFACTUTRERS ASSOCIATION
18 NACE NATIONAL ASSOCIATION OF CORROSION ENGINEERS INTERNATIONAL
19 NBCC NATIONAL BUILDING CODE OF CANADA
20 NISD NATIONAL INSTITUTE OF STEEL DETAILING
21 OSHA OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION
22 RCSC RESEARCH COUNCIL ON STRUCTURAL CONNECTIONS
23 SSPC STEEL STRUCTURES PAINTING COUNCIL / SOCIETY OF PROTECTIVE COATING
24 SSRC STRUCTURAL STABILITY RESEARCH COUNCIL
25 WSD WORKING STRESS DESIGN
26 SJI STEEL JOIST INSTITUTE
27 NDE NON DESTRUCTIVE EXAMINATION
28 NDT NON DESTRUCTIVE TESTING
29 BIF BILL INTERCHANGE FORMAT
30 CJP COMPLETE JOINT PENETRATION
37 PJP PARTIAL JOINT PENETRATION
31 E70LH E70-LOW HYDROGEN
32 ERW ELECTRIC RESISTANCE WELDING
33 FCAW FLUX CORED ARC WELDING
34 GMAW GAS METAL ARC WELDING
36 SMAW SHIELDED METAL ARC WELDING
35 SAW SUBMERGED ARC WELDNG
38 FR FULLY RESTRAINED MOMENT CONNECTION
39 PR PARTIALLY RESTRAINED MOMENT CONNECTION
40 SC SLIP-CRITICAL
41 SDNF STEEL DETAILING NEUTRAL FILE
42 SER/EOR STRUCTURAL ENGINEER OF RECORD
43 SOP STANDARD OFFICE PRACTICE
44 GTSM GOUGE TO SOUND METAL
45 CAD COMPUTER AIDED DRAFTING
46 CC CENTRE TO CENTRE
47 CG CENTE OF GRAVITY
48 CL CENTRE LINE
49 CNC COMPUTER NUMERIC CONTROL
50 DXF DRAWING INTERCHANGE FORMAT
51 GA GAGE
52 GOL GAGE ON ANGLE/GAGE OUTSTANDING LEG
53 HSS HOLLOW STRUCTURAL SECTION
54 HVAC HEAT VENTILATING AND AIR CONDITIONING
55 KSI KIPS PER SQUARE INCH
56 LBS LB = POUND
57 LHE LEFT HAND END
58 LLH LONG LEG HORIZONTAL
59 LLV LONG LEG VERTICAL
60 LSL LONG SLOT
61 LSLP LONG SLOTTED/LOAD PARALLEL HOLES
62 LSLT LONG SLOTTED/LOAD TRANSVERSE HOLES
63 MC MISCELLANEOUS CHANNEL / MOMENT CONNECTION
64 NS NEAR SIDE
65 OSL OUT STANDING LEG
66 OVS OVERSIZED
67 RD RUNNING DIMENSION
68 RFI REQUEST FOR INFORMATION
69 SSL SHORT SLOT
70 SSLP SHORT SLOTTED/LOAD PARALLEL HOLES
71 SSLT SHORT SLOTTED/LOAD TRANSVERSE HOLES
72 TBD TO BE DETERMINED
73 TC TENSION CONTROL
74 TYP TYPICAL
75 UDL UNIFORMLY DISTRIBUTED LOAD
76 UM UNIVERSAL MILL
77 UNO UNLESS NOTED OTHERWISE
78 SCBF SPECIAL CONCENTRICALLY BRACED FRAMES
79 EBF ECCENTRICALLY BRACED FRAMES
80 SMF SPECIAL MOMENT FRAMES
81 IMF INTERMEDIATE MOMENT FRAMES
82 OMF ORDINARY MOMENT FRAMES
83 VT VISUAL TESTING
84 PT PENETRANT TESTING
85 MT MAGNETIC-PARTICLE TESTING
86 UT ULTRASONIC TESTING
87 RT RADIOGRAPHIC TESTING
88 LASER LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION
89 AASHTO AMERICAN ASSOCIATION OF STATE HIGHWAYS AND TRANSPORTATION OFFICIALS
90 AREMA AMERICAN RAILWAY ENGINEERING AND MAINTAINANCE OF WAY ASSOCIATION
91 CASE COUNCIL OF AMERICAN STRUCTURAL ENGINEERS