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. SARS 0120 : Par1 5 Sec1 ton HE-L981 Suhhase PART 5 : CONTRACT ADMlNISTRATlON SECTION ME CONTENTS Clause Page Number START OF CONSTRUCEION 1 General . 1 I
4、DIAT Y AFTER THE HANDING OVER OF THE SITE 1 Sources of Material Supply 1 Stabilizing Small Areas . 1 Supply oE Lime 1 DURING CONSTRUCTLOB . 1 Methods of Construcion . 1 . Hand spreading oE stabilizing agenL 1 Curing (application oE water) . 1 Administration 1 Varying physical properties of borrow pi
5、Ls 1 Mixing-in of stabilizing agent . 1 Testing 1 QUALITI CONTROL AND OTHER CONSIDERATIONS . 1 SABS 0120 : Part 5 Section ME-1981 Subbase SARS 1200 ME : SUBBASE MITE: The clause nmber(s) given at the beginning or after the he-ding of a clause idare, unless otherwise stated, the nwher(s) of the relev
6、aut clause(s) of SABS 1200 ME. START OF CONSTRUCTION GENERAL. For the purposes of this part of the code contract administration starts with instructions to the contractor to complence work as set out in Subclause 4.1 of Section 0. IEIMEDUTELI APTER THE HANDING OVER OF THE SITE SOURCES OF MATERIAL SU
7、PPLY (Suhclause 3.5.1). The contractor should establish and prove hLs scwrces of supply and obtain the engineers approval of both material and source early enough to ensure that the work is not delayed, particularly where problems are expected. STABILIZENG WALL ARPAS (Subclauee 5.5.3). The applicati
8、on and mixing in of stahilizing agent to small areas must necessarily be done by hand hut on large areas the operation may warrant the use of a mechanical spreader. The contractor and the engineer should reach agreement early in the contract as to the method that will be adopted (see 3.2). SUPPLY OF
9、 LIME (Subclause 3.3.2). Where delays in supply are inevitable and no provision has been made in the contract document for such a contingency, the contractor and the engineer should reach early agreement on any amendments to the specification that are required, to prevent unnecessary dispute. (See S
10、ubclase 1.2.1 of Section ME of Part 3 of the code.) DURING CONSTRUCTION METHODS W CONSTRUCTION Hand Spreading of Stabilizing Agent (Suhclause 5.5.3). When hand spreading is allowed. pockets or bags of stahilizing agent should be accurately spaced at such equal intervals along the section to he stabi
11、lized as to provide the rate of application required (see Subclause 5.5.1 of SABS 1200 ME). The pockets or bags should then be opened and the stabilizing agent spread in transverse rows across the full width of the area to be treated. Such spreading should be done as evenly as possible, and uniform
12、distribution of the stabilizing agent over the entire area to be treated should then be obtained by levelling oEf the rows of stabilizing agent by weans of hand rakes andfor screeds. Curing (Application of Water) (Subclause 5.5.6). Depending on the stabilizing agent being used the details of curing
13、my be varied but proper curing is of utmost importance. The contractor is warned that successive applications of water to completed work that is allowed to dry out between water applications, may cause the treated layer to disintegrate and thus completely nullify the intended ef Eect of proper curin
14、g. Where possible,water should be applied from the side of the road or by means of a water cart the axle mass loads of which conform to the applicable requirements of the Road Traffic Ordinance. Varying Physical Properties of Borrow Pits (Subclause 3.5.1). Both engineer and contractor should react q
15、uickly to make alternative arrangements when the material exposed in a designated or previously approved borrow pit is found to differ from that previously excavated. Mixing-In of Stabilizing Agent (Subclause 5.5.4) -. Mixing should be done by means of graders, disc harrows, or rotary mixers (or oth
16、er acceptahle equipment), working over the full width and depth of the layer to be stabilized by means of successive passes of the equipment. The onus is on the contractor to ensure that the mixing is uniform and adequate. “One-pass“ machine. The onus is on the contractor to satisfy the engineer tha
17、t any “one-pass“ stabilizing machine he proposes to use to apply the stahilizing agent and water will apply the required amounts and that satisfactory results will be obtained from the use of such a machine. Testing Frequencies (Subclause 7.2.1). Although Subclause 7.2.1 of SABS 1200 UE permits the
18、frequency of testing to be reduced when the material is homogeneous, it is necessary that the engineer and the contractor reach early agreement on the advisability and the extent of such a reduction. Stabilizer content (Subclause 7.3.3). A requirement that the stabilizer content of the layer when de
19、termined by analysis should be at least 60 X (or any other percentage) of the ordered stabilizer content has been omitted from Subclause 7.3.3 of SABS 1200 HE because this manner of control is regarded as impractical for the following reasons: a) Both the sampling and the method of testing soils tha
20、t contain varying proportions of the same elements that are being determined in the tests are problematical. b) Variations in the distribution of stabilizer (longitudinally, laterally, and with depth) are inwitable in the construction process. c) Analysis of the test results normally requires a set
21、of 20 consecutive test results. However, where the project or the amount of work completed at a particular time is such that fewer than 20 test results are available, the engineer will have to apply the analysis to the smaller number. QUALITY CONTROL AND OTHER CONSIDERATIONS The relevant recommendations of SABS 0157) should be applied to the construction of a suhbase. - l) Quality management systems. May 1981 Approved by the COUNCIL OF THE SOUTH AFRICAN BUREAU OF STANDARDS
