1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS 7906-2:2000 Incorporat
2、ing Corrigendum No. 1 ICS 53.020.99; 91.080.10; 97.200.10 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Lifting equipment for performance, broadcast and similar applications Part 2: Code of practice for use of aluminium and steel trusses and towersThis British Standard, havi
3、ng been prepared under the direction of the Engineering Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 July 2000 BSI 07-2000 The following BSI references relate to the work on this standard: Committee reference MHE/3/13 Draft for comment 99
4、/706163 DC ISBN 0 580 33162 8 BS 7906-2:2000 Amendments issued since publication Amd. No. Date Comments 11026 Corrigendum No. 1 July 2000 Corrections to inside front cover. Other corrections indicated by a sideline in the margin. Committees responsible for this British Standard The preparation of th
5、is British Standard was entrusted by Technical Committee MHE/3, Cranes and derricks, to Subcommittee MHE/3/13, Lifting equipment for performance, broadcast and similar applications, upon which the following bodies were represented: Association of British Theatre Technicians Broadcasting Entertainmen
6、t Cinematograph and Theatre Union H.S.E ITV Association (ITVA) Lifting Equipment Engineers Association Professional Lighting and Sound Association Safety Assessment Federation Ltd Theatres Advisory CouncilBS 7906-2:2000 BSI 07-2000 i Contents Page Committees responsible Inside front cover Foreword i
7、i 1 Scope 1 2 Normative references 1 3 Definitions 1 4 Manufacturers guidelines and recommendations 3 5 Applied loads 3 6 Handling 3 7 Erection 3 8 Inspection 4 Bibliography 7 Figure 1 Components of a typical truss or tower module 2ii BSI 07-2000 BS 7906-2:2000 Foreword This British Standard has bee
8、n prepared by Subcommittee MHE/3/13, Lifting equipment for performance, broadcast and similar applications. There are no specific British Standards that cover the design, manufacture and use of aluminium or steel trusses in the entertainment industry. It should be noted that other British Standards
9、may be relevant, depending on the application and intended use. In an attempt to improve safety and standards in the entertainment industry, the Entertainment Services and Technology Association (ESTA) of New York, USA, convened a series of meetings to prepare a draft standard for the American Natio
10、nal Standards Institute. The preparation of the draft standard was entrusted to the Truss Team working as part of the Rigging Work Group for the Technical Standards Committee (TSC) of ESTA. The Truss Team generally consisted of manufacturers and their structural engineering advisors. This British St
11、andard is based on the American draft standard. It has been assumed in the drafting of this British Standard that it is used by suitably qualified and experienced people and organizations. This British Standard provides a coordinated set of recommendations that can also be a guide to government and
12、other regulatory bodies and municipal authorities responsible for guarding and inspection of the equipment falling within its scope. Safety codes and standards are intended to enhance public safety. Revisions result from committee consideration of factors such as technology advances, new data, and c
13、hanging environmental and industry needs. Revisions do not imply that previous editions were not adequate. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British St
14、andard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 7 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Sidelining
15、in this document indicates the most recent changes by amendment. BSI 07-2000 1 BS 7906-2:2000 1 Scope This British Standard provides recommendations on the use of aluminium and steel trusses, towers and associated structural components such as tower head blocks, sleeve blocks, bases, and corner bloc
16、ks in the entertainment industry. This British Standard covers truss beams and two dimensional ladder beams but does not cover individual, separate rigging hardware (half couplers, shackles, wire ropes, etc.). This British Standard covers a variety of uses that are confined to the entertainment indu
17、stry and applies to a range of structures subjected to normal atmospheric conditions. This British Standard does not cover the use of curved shell structures or structures subjected to severe thermal or chemical conditions. This British Standard is not intended to be used for the design of containme
18、nt vessels, airborne structures, or vessels, or for any application covered by another standard. Requirements for design and manufacture of the equipment covered by this British Standard are given in BS 7905-2. Wherever “truss” is referred to in this British Standard, it equally applies to “tower” a
19、nd vice versa. “Truss” also applies to associated structural components. 2 Normative references The following normative document contains provisions that, through reference in this text, constitute provisions of this British Standard. Subsequent amendments to, or revisions of, this publication do no
20、t apply. BS 7905-2:2000, Design of lifting equipment for performance, broadcast and similar applications Part 2: Specification of trusses and towers. 3 Definitions For the purposes of this British Standard the following definitions apply. NOTE Figure 1 shows some components of a typical truss or tow
21、er module. 3.1 abrasion loss of material due to wear 3.2 allowable load maximum static equivalent load imposed on truss/tower in addition to the self-weight 3.3 ancillary supplementary 3.4 camber intended vertical deviation of a truss, usually radiused 3.5 chord element of a truss or tower module th
22、at carries axial forces associated with flexure or axial loading 3.6 competent person person with sufficient practical and theoretical knowledge and experience to carry out the persons duties, and who is aware of the limits of the persons competency, expertise and knowledge 3.7 connecting plates pla
23、tes welded to the end frames of a truss or tower module, used to connect adjacent modules together 3.8 crack crevice type discontinuity in a material 3.9 damage condition that adversely affects the intended use of a truss module (usually load carrying capacity) 3.10 dent local deformation resulting
24、in measurable change in cross section of member or element 3.11 diagonal element of a truss or tower module that is at an angle to the main chords 3.12 dye penetrant test standard non-destructive test that highlights cracks in welds 3.13 lacing member secondary member between chords 3.14 manufacture
25、r person or company who fabricates truss/tower modules or systems 3.15 module singular framed structure built up entirely from tension and compression members, arranged in panels so as to be stable under load2 BSI 07-2000 BS 7906-2:2000 Tophorizontal Panelpoint aka:node Horizontaldiagonal Vertical C
26、hord Topview Sideview Bottomhorizontal Bottomview Verticaldiagonal Endview Internaldiagonal Figure 1 Components of a typical truss or tower module 3.16 panel point junction of one or more lacing members with a chord 3.17 pinned connection end tube connection that uses a removable pin to connect trus
27、s modules 3.18 qualified person person who, by possession of a recognized degree or certificate of professional standing, or who by extensive knowledge, training, and experience, has demonstrated the ability to solve problems relating to the subject matter and work 3.19 regular service normal use wi
28、th repetitive assembling and dismantling 3.20 skin material cover to a truss structure NOTE A skin is normally used on a roof system. 3.21 sweep intended lateral deviation of a truss, usually radiused 3.22 tower one or more modules, usually square or triangular, assembled vertically to carry primari
29、ly axial load 3.23 truss one or more modules, generally horizontal, assembled to carry load over a distance, primarily in flexure 3.24 user person or company who assembles or uses truss or tower modules or systems BSI 07-2000 3 BS 7906-2:2000 4 Manufacturers guidelines and recommendations The manufa
30、cturers guidelines and recommendations on usage should be complied with at all times unless otherwise recommended by a qualified person. If the proposed use is not covered by the manufacturers recommendations, a qualified person should be consulted. The allowable loads, bending moments and shear for
31、ces specified by the manufacturer should not be exceeded unless otherwise recommended by a qualified person. 5 Applied loads 5.1 The user should assess all loads on the fully assembled truss system. Full consideration should be made of the weight of all equipment, including, but not limited to, any
32、motors, light and sound equipment, multicore cables, follow-spot chairs, temporary personnel occupancy, and reactions from fall protection lines. 5.2 The user should consider the following: a) disposition of the loads on the trusses, and whether they are evenly balanced beneath the centreline of the
33、 truss, or, as is more often the case, whether they are mainly concentrated to one side or other; b) the increase in weight of the multicore cables towards the point of entry of the cables onto the trussing; c) the possible dynamic effects on the trusses from raising and lowering of the suspended eq
34、uipment, or from raising and lowering of the completed truss system; d) the wind forces that could be applied to the truss system during erection, when complete and when in an unloaded as well as the fully loaded state (it is essential that consideration is given to the wind forces from items attach
35、ed to the truss structure, e.g. banners, roof skins, sound and lighting equipment, projection screens, scenery); e) the effects of changes in temperature during use of the truss system, of the weight of any snow on the system or any covering, of the possibility of seismic action affecting the overal
36、l stability of the system, and the possibility of accidental impact damage when the system is operational; f) the most suitable way to attach hardware so as not to cause damage. 6 Handling 6.1 Individual modules and fully assembled trusses, and any ancillary components that form part of a complete s
37、ystem, should be carefully handled to avoid impact damage or abrasion. 6.2 Trusses should not be dragged. Trusses should be carried or moved on dollies or trolleys, and laid down carefully. 6.3 Trusses should be properly secured and supported during transportation, and should be stacked with spacers
38、 between successive heights to limit abrasion. 6.4 End connections should be protected from damage. 7 Erection 7.1 Detailed layout drawings and calculations should be prepared to cover each time the trussing is to be used, and should include the following information: a) accurate overall dimensions;
39、 b) distribution and/or location of applied loads; c) location of suspension points. 7.2 Care should be taken to ensure that trussing is assembled and erected correctly in accordance with the layout drawings and calculations. 7.3 Truss modules should be inspected before assembly in accordance with c
40、lause 8. Truss modules should be assembled, joined together, and erected by competent persons. 7.4 If the trusses are to be supported on towers that form part of the complete trussing system, a full assessment should be made, by a qualified person, of the load-carrying abilities of the ground on whi
41、ch the towers are to be erected. The ground should be improved if required to provide a suitable bearing surface. Spreader plates should be provided beneath the tower bases if required. 7.5 If the trusses are to be suspended from the roof beams or other structure within an existing building, or from
42、 a framework that is not part of the complete trussing system, then a full assessment should be made, by a qualified person, of the roof beams or other structure. The position of the suspension points should be moved to the optimum, as appropriate, or suitable strengthening measures should be made t
43、o the existing structure. NOTE Lifting and suspension of trusses should be carried out in accordance with BS 7906-1 (under preparation). 7.6 After initial erection, the truss assembly should be inspected by a competent person.4 BSI 07-2000 BS 7906-2:2000 8 Inspection NOTE This clause provides minimu
44、m inspection routines and guidelines for the truss user. Although every effort is made to provide a thorough list of situations and inspection criteria, a complete list is beyond the scope of this British Standard. 8.1 General Advice should be sought by the user for specific inspection routines from
45、 the manufacturer or a qualified person. Inspection routines should define the level and frequency of the inspections. 8.2 Inspection levels 8.2.1 Initial inspections When first acquired, either new or used, truss modules should be inspected, in accordance with 8.4, and a record of the inspection ma
46、intained. 8.2.2 Regular inspections Regular visual inspections should be carried out in accordance with 8.4. Regular inspections should be performed by a competent person and should be carried out prior to each use and after any incident that could damage the truss system. 8.2.3 Periodic inspections
47、 Periodic visual inspections should be carried out in accordance with 8.5, and a record of the inspections maintained. Periodic inspections should be performed by a qualified person and should be conducted at least once each year or in accordance with an inspection routine established by a qualified
48、 person. 8.3 Inspection frequency 8.3.1 Truss in regular service Truss modules in regular service should be subjected to regular and periodic inspections (see 8.2.2 and 8.2.3). 8.3.2 Truss not in regular service Truss modules not in regular service should be inspected with regard to the conditions o
49、f storage when returned to service. If the equipment has been stored correctly, an inspection should be carried out in accordance with 8.4. If the equipment has not been stored correctly, an inspection should be carried out in accordance with 8.5. 8.3.3 Permanent installations, stationary Periodic inspections should be carried out on all truss modules that are permanently installed in a stationary (non-movable) configuration. The frequency of inspections should be determined based on the prevalent conditions. 8.3.4 Permanent installations, moving Periodic i
