|
|
南非土木工程施工标准 LD:下水系统 英文原文节选 20100079 1-29 |
RISING MAINS. The relevant requirements for materials of SABS 1200 L shall apply if a rising main forms
part of the sewerage system.
BEDDING. The requirements for bedding of SABS 1200 LB shall apply.
MANHOLES, CHAMBERS, ETC.
Bricks. Bricks shall be obtained from an approved manufacturer and shall be either general purpose
(special) burnt clay bricks that comply with the applicable requirements of SABS 227, or Class 514
calcium silicate bricks that comply with the applicable requirements of SABS 285. The Contractor shall
submit to the Engineer samples of the bricks that he intends using in the construction of the Works (see
Subclause 3.1 of SABS 1200 A or SABS 1200 AA, as applicable). The samples of bricks that are approved
will be rctained by the Engineer.
Precast Concrete Sections. Precast concrete sections shall comply with the applicable requirements of
SABS 1294. Sectional spun concrete cylinders shall have been manufactured from dolomitic aggregate where
so required in terms of the project specification, and shall comply with the requirements for pipes of SC
type and Class A of SABS 677.
The joints shall be sealed in an approved manner to form a watertight joint (see Drawing LD-5).
Prefabricated AC Manholes. If prefabricated AC manholes are permitted in terms of the project
specification, they shall comply with the applicable requirements.
Concrete. Except as required in 3.5.2 and except that only dolomitic aggregate shall be used where so
required in terms of the project specification, concrete shall comply with the requirements of SABS
1200 GA or SABS 1200 G, as applicable.
-Sand.
sand, and shall be free from clay and other impurities and, If so directed, shall be properly screened
and washed.
Mortar. Mortar for brickwork and plasterwork shall be composed of one part of cement to three parts of
sand by volume.
Step Irons.
BS 1247 and shall be of length suitable for fixing in brick, cast-in-situ concrete, prefabricated
asbestos cement, or precast concrete, as applicable.
Manhole Covers and Frames.
SABS 558, and except where other types are scheduled, shall be of Type 2A in the case of manholes in
roads and other areas subject to road-traffic loads, and of Type 4 in the case of manholes in areas not
subject to such loads.
MARKER POSTS. Marker posts shall comply with the applicable requirements of the project specification.
PLANT
PIPE IIANDLING AND HIGGING EQUIPMENT.
handling and placing of pipes shall be of the type recommended by the pipe manufacturer and such that at
no time during operations covered by the specification is any pipe shell overstressed.
SETTING OUT. The apparatus used for the line, level, and positional control of pipelaying shall be
accurate, sturdy, and in good working order. The Contractor may use any acceptable device for such
control, includiny a device incorporating one or more laser beams.
TESTING. In addition to the pumps, gauges, storage tank, tools, plugs, bracing, and fittings necessary
for the tests required in terms of Clause 7, the Contractor shall provide suitable equipment for the
location of faults up to the date of issue of the final certificate.
CONSTRUCTION
TRENCH BOTTOM. The trench bottom shall be prepared as specified in SABS 1200 DB. Trenches shall be kept
sufficiently dry to allow proper and safe bedding, laying, and jointing of pipes and kept dry until the
pipeline has passed the required tests and construction of the selected fill blanket over the pipes has
been completed.
LAYING AND BEDDING
Preliminary Inspection.
damage immediately before laying. The onus of detecting damaged pipes and fittings before installation
shall be 011 the Contractor. Should any damaged pipe or fitting be found in the sewer after it has been
laid, the damaged item shall be removed and replaced at the Contractor's expense.
Alignment. Pipes shall be laid on the specified bedding cradle true to designated line and level, and
the bedding shall be placed and compacted in accordance with the applicable requirements of Subclause 5.2
of SABS 1200 LB. Designated invert levels shall take precedence over design depths shown on drawings.
The completed sewer shall have no bends or undulations except where shown on the drawings or as directed.
AC pipes that have any deviation from straightness (see SABS 819). shall be so laid that preference is
given to level over line.
Method. The method of laying and bedding shall be such that
a) barrels of pipes bear evenly on the bedding for their full length;
b) no packing is used under the barrels; and
c) no socket or coupling bears on the bedding.
Where the slope of a pipe is greater than 1 in 10, anchor blocks shall be constructed to the details
shown on Drawing LD-1.
Cutting. Pipes shall be so cut as to obtain a clean end.
Pipes of Different Materials.
special adaptors recommended by the pipe manufacturer(s1.
-
Joints between cylinders shall be of the interlocking self-centring type.
Sand shall be clean pit sand or, if so required in terms of the project specification, dolomitic
Step irons shall comply with the applicable requirements for malleable CI step irons of
Manhole covers and frames shall comply with the applicable requirements of
The plant and rigging equipment used bf the Contractor for the
Each pipe and fitting shall be thoroughly cleaned out and carefully examined for
Pipes and fittings of different materials shall be jointed only with原件下载： 
|
|
|
|
