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 01 20-3 Section MH:1996 Asphalt base and surfacing First revision Part 3 : Guidance for design Section MH Contents Page 1 Pre-tenderconsiderations 1
4、 1.1 Investigations 1 1 .l .l Bituminous binders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Administration 1 1.2.1 Tenders 1 1.3 Documentation . 1 1.3.1 Particularrequirements . l 1.3.2 Nominal
5、 rates of application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . 1 2 Designrequirements . 1 2.1 General . :. 1 2.2 Materials 1 2.2.1 Bituminous binders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2.2.2 Aggregates l 2.3 Grading . 1 2.4 Stability, flow and stability/flow ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l 2.5 Design
7、of open-graded asphalt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3 Applicabilityofothercodes . 2 4 Testprocedures . 2 5 Quality control and other considerations . . . . . . . . . . . . . . . . . . . . . . . . . .
8、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 First Revision 24 June 1996. This section of the code supersedes SABS 0120-3 : Section MH:1981 Approved by the PRESIDENT OF THE SOUTH AFRICAN BUREAU OF STANDARDS CODE OF PRACTICE SABS 01 20-3 : Section MH:1996 SABS 1200 NIH
9、 : Asphalt base and surfacing NOTE - The clause number(s) given in brackets at the beginning or after the heading of a clause islare, unless otherwise stated, the number(s) of the relevant clause(s) of SABS 1200 MH. 1 Pre-tender considerations 1 .l lnvestlgations 1 .l .l Bituminous binders (3.4) Inv
10、estigate the likely location of bus stops and other fuel spillage risk areas. (See also 2.2.1 below.) 1.2 Administration 1.2.1 Tenders Ensure that action has been taken on the matters set out in 3.1.2(a) and (b) of the Introduction to SABS 0120, before the start of construction. 1.3 Documentation 1.
11、3.1 Particular requirements Take the recommendations given in 3.2.1 to 3.2.12 of section MH of SABS 0120-2 into account when compiling the project specification and schedule. 1.3.2 Nominal rates of application The nominal rates of application specified should be as close as possible to the rates tha
12、t will be required. This will ensure that variations could be positive or negative so that realistic tendered rates for variations will be obtained. 2 Design requirements 2.1 General Design should be based on the relevant recommendations given in TRH 8). 2.2 Materials 2.2.1 Bituminous binders 2.2.1.
13、1 Only specify the use of tars after careful consideration and in special circumstances. A bitumen is the prefered binder for asphalt surfacing because, except where oil or fuel spillage is expected (e.g. at bus stops), a surface produced with tars generally has a lower durability than one produced
14、with bitumen. 2.2.1.2 Lurgi tars have not yet been adequately proved and should be used only after careful consideration. 2.2.2 Aggregates In the case of a continuously graded asphalt, use an aggregate blend that consists of crushed rock and, if required, a mineral filler. In the case of gap-graded
15、asphalt, natural sand may be used instead of crushed rock fines. A mixture of crushed rock fines and sand may be used if blending of the two materials can be carried out to the satisfaction of the engineer. 2.3 Grading 2.3.1 Grading is the only criterion that may be specified for open-graded mixes (
16、see 2.5 below and table 4 of TRH 8). 2.3.2 In the case of continuously graded mixes, give precedence to specifying the Marshall criteria, since they bear directly on the quality of the end product. However, as control of grading assists to a large extent in achieving compliance with the specified Ma
17、rshall criteria, the grading for continuously graded, gap-graded and semi-gap-graded asphalt is specified as being subject to the requirements for the Marshall criteria (see 3.5.8 of SABS 1200 MH). 2.4 Stability, flow and stabilitylflow ratio The values given for stability, flow, and stabilitylflow
18、ratio in table 6 of SABS 1200 MH might not be suitable for a road in hilly terrain and expected to carry very heavy traffic. Under these circumstances, the stabilitylflow ratio should be at least 2,O kN1mm. 1 ) Selection and &sign of hot-asphalt surfacings for highways, published by the NITRR. SABS
19、0120-3 Section MH:1996 Asphalt base and surfacing First revision 2.5 Design of open-graded asphalt As the use of open-graded asphalt in South Africa is a relatively recent development, proved design neth hods are not yet available. Details of a tentative method are given in appendix E of TRH 8). (Se
20、e also 2.3.1 .) 3 Applicability of other codes There are no SABS codes of practice that are applicable to the design of asphalt base and surfacing, but the recommendations of the relevant TRH publications should be taken into account. 4 Test procedures The test procedures !jet out in the appendices to TRH 8) are generally applicable. 5 Quality contrcd and other considerations Apply the relevant recommendations of SABS IS0 9000) to the design of asphalt base and surfacing. 1) Selection and design of hot-ashpalt for highways, published by the NITRR. 2) Quality managemen! systems. sabs pta
