SANS 10120-5 HB-1985 Code of practice for use with standardized specifications for civil engineering construction and contract documents Part 5 Contract administration Section HB C.pdf

1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA

2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any

3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. SABS 012u : Part 5 Section BB-1985 Cladding and sheetinq Clause 1 . 1.1 2 . 2.1 3 . 3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.1.5 3.1.6 3.1.7 3.2 3.2.1 3.2.2 3.2.3 4

4、 . PART 5 r CONTRACT ADMINISTRATION SECTION HB START OF CONSTRUCTION General IMMEDIATELY AFTER THE AWARD OF TBE CONTRACT Data given on Detail Sheets DURING CONSTRUCTION Methods of Construction . Installation of sheeting Precautions when using valley fasteners . Wet-storage stain prevention . Alumini

5、um sheetinq . Drilling End-lap sealing . Dealing with oil canning . Administration . Approved manufacturers Organizing for efficiency and savings Testing QUALITY CONTROL AND OTHER CONSIDERATIONS . Page Nuniber February 1985 Approved by the COUNCIL OF THE SOUTH AFRICAN BUUREU OF STANDARDS SABS 0120 :

6、 Part 5 Section HB-1985 Cladding and sheeting SABS 1200 HI3 : CLADDING AND SHEETING NOTE: The clause number(s) given at the beginning or after the heading of a clause is/are. unless otherwise stated, the numberls) of the relevant clause(s) of SABS 1200 HB. START OF CONSTROCTIQN GENERAL. For the purp

7、oses of this part of the code, contract administration starts with instructions to the contractor to comuence work as set out in subclause 4.1 of Section 0 of Part 5 of the code. IMMEDIATELY AFTER THE AWARD OF THE CONTRACT DATA GXVEN ON DETAIL SHEETS. If, for some reason, such as reluctance to delay

8、 the issue of instructions to commence construction, not all the data given on the detail sheets was approved before the contract was awardea, the engineer should ensure that a) agreement in writing is reached on all detail data not previously agreed upon1 and b) where he has agreed to changes or ha

9、s approved different details, agreement is reached as regards prices where these may differ from those tendered. (See Subclauses 1.2.1 and 1.2.3 of Section HB of Part 3 of the code.) WRING CONSTRUCTION METHODS OF CONSTRUCTION Installation of Sheetinp (Subclause 5.5) Tolerance requirements for instal

10、lation (Subclause 6.2.1). Before coaaencing erection, the sheeting contractor should check the alignment of the purlins and girts to which sheeting7 and cladding is to be attached, because he will be held responsible and will be required to bear the cost of rectification should the finished faces no

11、t comply with the specified requirements. The cost of rectifying any misalignments found before the sheeting contractor commences erection should be borne by the contractor who erected the structure. Installation and fixin9 The manufacturers instructions for the installation and fixing of sheets sho

12、uld be followed. Holes for fixing should always be drilled, not punched, because punching not only splays out the aperture and weakens the material but may start a crack that will open out as a result of weathering. on no account should fixing screws or the nuts on fixing bolts be screwed down tight

13、ly, and care should be taken not to deflect the sheets at intermediate purlins in an attempt to make the sheets bear on these purlins. Precautions when using Valley Fasteners (subclauses 5.5.2.1 and 5.5.3). Crown fasteners have been used traditionally, especially with corrugated sheeting, as sealing

14、 of the sheet at the fixing hole is easier than when valley fasteners are used. However, in some recently developed systems in which the roof sheeting acts as bracing to the roof structure, valley fasteners are used in order to ensure intimate contact between the roof sheeting and the supporting str

15、ucture. Where valley fasteners are used, the attention of the contractor and the engineer is drawn to the necessity of ensuring adequate and permanent sealing around the fixing hole to prevent the ingress of moisture. Wet-storage Stain Prevention (Subclauses 5.1.2 and 5.2.2). To avoid the problem of

16、 wet-storage stain formation it is essential that zinc-coated sheets be stored under conditions of free air circulation and that significant temperature changes which cause condensation be avoided. Provided that wet-storage stain is arrested early in its formation (i.e. before pitting comences), the

17、 materials can be reclaimed by cleaning the surface and then coating the affected area with an inhibitor oil. Aluminium Sheetinq (Subclause 5.2). Care should be taken during the handling, transportation and storing of aluminium sheets to protect the corners, edges and ribs from damage. Aluminium she

18、ets should be stored under cover, clear of the ground and away from risk of damage by building operations. Contact with cement dust, lime and abrasive dust should be avoided as this may result in surface discoloration which may be difficult to remove. This discoloration is, however, an appearance de

19、fect only and will not affect the corrosion resistance of the metal. Drilling (Subclause 5.5.2.1). Where painted or plastics-coated sheeting is drilled in packs, hot swarf and metal dust are trapped between the sheets, become embedded in the surface coating and may corrode after the sheets have been

20、 erected. End-lap Sealing (Subclause 5.5.3). Effective and acceptable end-lap sealing is the responsibility of the contractor. Such sealing can be achieved by the provision of two runs of sealer, and by tail stitching. Dealing with Oil Cannina (Subclause 5.5.4). When galvanized sheeting is manufactu

21、red in strip form there is a tendency for the zinc coating to build up on the edges of the strip. When the galvanized strip is coiled this zinc build-up increases the diameter of the coil at the edges relative to the centre of the coil. Thus the metal is stretched to varying degrees at the edges and

22、 this induces stresses in the steel strip. During the manufacture of profile sheets these stresses manifest themselves in the fom of oil canning i.e. ripples in the metal. Oil canning may also be induced by incorrectly aligned or inadequately braced steelwork. Oil canning is not detrimental to the w

23、atertightness of the sheeting or to the life expectancy of the material but may be given as a cause for rejection on those grounds or on grounds of unsightliness. ADMINISTRATION Approved Manufacturers (Subclauses 3.2, 3.4 and 7.1.4). Because certain requirements of SABS 1200 HE are dependent on thos

24、e of “approved manufacturers“ the contractor should determine the identity of those manufacturers before materials are mved onto the site (see Subclause 1.2.4 of Section HB of Part 3 of the code) . Organizing for Efficiency and Savings (Subclause 5.5.1). For maximum efficiency and econmy the contrac

25、tor should ensure that all materials, including sheeting accessories. fixings and sealants, required for a particular area of sheeting are on site timeously and are conveniently placed before work begins. Sl)gS 0120 c Part 5 Section HB-1985 Cladding and sheeting 3.2.3 Testinp (Subclauses 7.1-7.3). T

26、he load tests are intended to asses5 the resistance of roof sheeting and its fasteners to lifting of the sheets under wind pressure and to collapse should a person tread on or fall onto any part of a roof. As the purlins and the supporting structure a-re not being tested they may be strengthened or stiffened for the purposes of the tests. 4. QIJRLITY CONTROL AND OTHER CONSIDERATIONS 4.1 The relevant reconmendations of SABS 0157) should be applied to the inst.allation of cladding dnd sheeting. 1) uality management systems.