SCOPE
This specification covers the requirements for precast concrete that is reinforced normally or that is to
be prestressed in accordance with the requirements of SAHS 1200 GF.
NOTE: The standards referred to in the specification are listed in Appendix A.
INTERPRETATIONS
SUPPORTING SPECIFICATIONS. Where this specification is required for a project, the following
specifications shall, inter alia, form part of the contract document:
a) Project specification;
b) SABS 1200 A or SABS 1200 AA or SABS 1200 AH, as applicable;
c) SABS 1200 G; and
d) in the case of a project that includes prestressed concrete work, SABS 1200 GF.
APPLICATION. This specification contains clauses that are generally applicable to structural preCaSt
concrete. Interpretations and variations of this specification are set out in Portion 2 of the project
specification which precedes this specification in a contract document.
DEFINITIONS AND ABBREVIATIONS. For the purposes of this specification, the definitions and abbreviations
given in the applicable of the specifications listed in 2.1 and the following abbreviations shall apply:
PBFC : Portland blastfurnace cement
OPC/slag : A blend of portland cement and milled granulated blastfurnace slag
MATERIALS
GENERAL.
relevant requirements of Clause 3 of SABS 1200 G.
CONCRETE. The concrete mix shall be of Grade 30 unless another grade is scheduled, shown on the
drawings, or specified in the project specification.
STORAGE CAPACITY AND DETERIORATED MATERIAL. The storage capacity provided shall be adequate and shall
comply with the requirements of Subclause 3.7 of SARS 1200 G.
Material that has deteriorated or that has been contaminated or damaged shall not be used. Such material
shall be removed from the Site without delay.
In addition to complying with the requirements of 3.2 and 3.3, materials shall comply with the
PLANT
GENERAL. In addition to complying with the requirements of 4.2-4.5, plant and equipment (including
formwork and moulds) shall comply with the relevant requirements of Clause 4 of SABS 1200 G.
CASTING BEDS, MOULDS, AND FORMWORK. All casting beds shall be properly aligned and levelled. The layout
shall be such that work being carried out on any unit(s) does not interfere with or adversely affect
adjacent operations. Adequate weather protection shall be provided should this be necessary to achieve
the specified standard. Moulds and formwork shall be such that the concrete surfaces and arrises can
comply with 5.3.
CONCRETE MIXERS. The concrete mixers used shall be specially suited to the production of low slump
concrete. Particular attention shall be paid to matching the mixer capacity to the required output.
VIBRATING EQUIPMENT. Vibrating equipment, whether in the form of a vibrating table, an external vibrator
attached to a mould, or an immersion vibrator, shall have a frequency that is suitable for the compaction
of low slump concrete, and shall have a capacity that exceeds the output of the concrete mixer with which
it is used.
HANDLING, LIFTINC;, AND STACKING. The Contractor shall provide adequate equipment for so handling,
lifting, and stacking precast units that they do not become discolored and are protected from permanent
damage due to stresses induced during handling or stacking or due to the use of slings, chains, and
hooks.
CONSTRUCTION
GENERAL. in addition to complying with the requirements of 5.2-5.6, the Contractor shall comply with the
relevant requirements of Clause 5 of SABS 1200 G except that, should any requirement of Clause 5 of SABS
1200 G conflict with any requirement of this specification, the requirement of this specification shall
prevail.
ROYALTIES. The Contractor shall indemnify the Employer against all claims for or on account of
infringement of patent rights, design, or trade mark in respect of any precast system used in connection
with the Works and the Contractor shall pay any royalties due or that may become due as a result of the
use of such a system.
PLACING AND VIBRATING OF CONCRETE. Concrete shall be so placed in moulds and vibrated that concrete
surfaces are smooth and even and all arrises are true and clean.
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