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 0120 : Part 3 Sect inn ME-1981 Subbase Clause 1. L. 1 1.1.1 1.1.2 1.1.3 1.2 1.2.1 1.3 1.3.1 1.3.2 1.3.3 1.3.4 2. PART 3 : GUlIIAMGT, FOR DESIGN SLGC
4、IOW HIS CONTWTS Page Nuiher PRE-TEN1)EI CONS11)EMTlONS 1 Lnvestlgatiom . 1 Sources OF supply of material . 1 Regional factor L Site inspection 1 Administration . Storage of lime . . . . . . . . . . . . Documentation General Width of subbase . UCS of cement-stabilized mat Stabilizing agent DESIGN REQ
5、UlREMENTS Ph3 losophy oE Design . . . . . . . .*.*.* -.*.-.* .*. .,-.*. .* rials .*.*.* S. .*,.* Design Details . 1 Thickness of Layer 1 APPLlCABILlTY OF OTHER COMES . 1 TEST PKOCEDUKES . I Test for Slaking of time I Test for Stabilizer Content and Efficiency of Mixing 2 Test for Density 2 QUALlTY C
6、ONTROL W OTHER CONSIDERATIONS . 2 SABS 0120 : Part 3 Section ME-1981 Subbase SAUS 1200 ME : SUBBASE NOTE: The clause nuanher(s) given at the beginning or arter the heading ol a clause islare, unlrss otherwise stated, the numher(s) of the relevant clausc?(s) of SAHS l200 ME. PRE-TENDER CONS C1)ERATIO
7、NS INVEST IGATIONS Sources of Supply of MateriaL. As part OF the pre-tender investigations identify and locate possible sources of supply OF material suitable for use in the sobbase. (See also Subclause 2.1 of Section ME of Part 5 of the code.) =anal Factor (Suhclause 3.2.1). Regional factors are sh
8、own on Drawing ME-2 of SABS 1200 ME. In addition to determining the applicable regional factor, decide whether the CBR shonld he varied to distinguish between roads that are expected to be lightly and heavily used. (See reference given in 2.2) Site Inspection. Ensure that the recommendations given i
9、n Clauso 6 of Section 0 have been followed. ADMINISTRATION Storage of L&% (Subclactse 3.3.2). In onler to ensure the supply of lime. the contractor may have to place orders well in advance of the required date and take delivcxy whenever the lime is available. with the result that the storage period
10、may be longer than is speciied or approved. If this is likely, insert a suitable clause in the project specification. General. Insert a suitable clause or clanses in Portion 2 of the project specification or give information on a drawing or include a suitahle item in the schedule of quantities to de
11、al with each matter listed in Clauses 1 and 2 of Section ME of Part 2 of the cod&. In addition, consider the recnmmendations given in Clauac 3 of Sect ion ME of Part 2 of the code and snch of those given in 1.3.2-1.3.4 below as are relevant to the project for which the contract document is being pre
12、pared. Width of Subbase. Show on the drawings the required width of the snhhase and give particnlar attention to the material required under the kerbing and the types of kerbing that will be acceptable. UCS of Cement-Stabilized Materials_ (Subclause 3.2.l(e). The valne of 0,75 MPa S ecified for the
13、UCS in Snbclause 3.2.l(e) of SABS 1200 ME is that given for subhase Class C4 in TRH q1T. Certain authorities specify higher values. However. in order to eliminate or minimize reflective cracking due to shrinkage cracks, the modern tendency is to lower the UCS requirements. Stabilizing Agent (Subclau
14、se 3.3.1). Consider using PC15 and F Ly ash in those parts of the country - where their osc is more economical than that of the material spcclfieil in Subclauses 3.3.l(a)-(d) of SABS 12W M1 NOTE: Granulated quicklime may he a cheaper material to purchase but more expensive to use. DESIGN REQU IKMENT
15、S PHLLOSOPBlY OF DESIGN. The philosophy of design for various levels of construction cost to suit the economic norms of services for urhan development that are set out in Section M is applicable to subbase design in general. DESIGN DETAILS. Consider the relevant requirements of TRH 4l) before finali
16、zing the design and the project specification requirements. THICKNESS OF LAYER. Design of the thickness and other features of subbase are dealt with in Clause 2 of Section M. APPLICASILUY OF OTHER CODES There are no SABS codes of practice that are applicahle to subhase design but the recommendations
17、 of the relevant TRH publications should be taken into account. TEST PROCEDURES TEST FOR SLAKING OF LIME. Take a sample oT lime, after the lime has been slaked on the road. and mix 400 g of the lime with 150 ml of water. Determhe the temperature of the mixture at 30 S intervals for a pericxl of 5 mi
18、n. The rise Ln temperature should not exceed 1 OC. Carry out at least six such tests on each lot or on the lime slaked during each days work. - l) Asphalt pavement design for national roads. published by the NITRR. May 1981 Approved hy the COUNCIL OF THE SCXWIl AFRICAN BUREAU OF SLINUARDS SABS 0120
19、: Part 3 Section NE-1981 Subbase TEST POI STABILIZRR CO ENT AND EFFLClENCY OF NlXlNG (Subclause 7.3.3). Use one of the applicable methods given in lrJ. See also Subclause 3.2.1.2 of Sect ton Hli of Part 5 of the code. TEST FOR DENSITY (Subclause 7.2.2). A section of subhase in whlch compaction has b
20、een wet1 controlled should give individual results for the density tesL that are not too IOW or too high. Test results should fall within the applicable of the ranges set out in Table 1. TABLE 1 - PERMlSSIBLE VARZATlONS IN IENSLTY 3 and 4 I : Spec ifled density (X of tnodified AASHTO maximum density
21、, 95 unstabilized 3 and 4 1 : Number OF tests per lot - 95 stabilized Mini mum and maximum variations fron the average density for any single Lest. X 3 and 4 I: 97 unstabilized 3 and 4 l : QUALITY CONTROL AND OTHEd CONSIDEUTIONS 97 stabilized Apply the relevant recommendations of SAUS 0157) to the design of a subbase. 2) Guide on prime coats, tack coals and Lernporary surfacing for he protc?cLion of bases, published by the I1TRR. 3) Quality management: systems. 3 and 4 5 6 %&S pta + 4.20 + 4.60 - + 5.00
