ROCLA Process

SPECIFICATION No. G.W.W. 58

MANUFACTURERS OF ROCLA PROCESS OF AUSTRALIA

Reinforced Cement .Concrete Cylindrical Pipes and Collars.

1.  DEFINITION.- Throughout this specification the following definition shall apply.

a) Pipe. The term “pipe” signifies a hollow cylinder made of cement concrete of uniform internal diametter and thickness of wall-through it length, except for the joint and suitably re­-inforced.

b) Collar.- The term “collar” signifies the jointing pieces similar in construction to the “pipe”described in (a) above except that it will be of a suitable short length.

2. TYPES OF PIPES.-
The pipes may be of two types

(a) Socket type, (b) Barrel type.

a) Socket type-In case of socket of similar joints the internal and external diameters at one and are enlarged to form _ a socket into which the spigot end of a similar pipe can enter to form a joint.

b) Barrel Type.- is an ordinary pipe of uniform internal diameter and thickness of wall throughout its length.

3. CLASSIFICATION OF PIPES.-
Reinforced cement concrete pipes may be classified as enumerated below:-

‘A’ Class (Non pressure) for. Sewerage, Storm Water
drainage and Culvert.

4. REINFORCEMENT.-
Reinforcing bars and or wire shall be of steel free from loose rust, scale, oil and grease or of steel having a higher tensile strength and complying with B.S.S. 785 and 1144. For reinforcement see Appendix ‘A’.

5.  CEMENT.-
The whole of the cement used in the manu­facture of pipes and fittings shall comply in all respect with the provisions of B.S. Specification No. 12 for – Portland cement, (ordinary or rapidhardening.)

6.  AGGREGATE.-
The Aggregate shall comply with the provisions of clause 3 and 3a B.S.S. 882. When required a sample of aggregate shall be submitted to the Purchaser
for approval with the tender. For pipes and fittings up to and including 3 inch nomnid internal diameter, the whole of the aggregate shall pass through a sieve having
mashes not exceeding 112 inch square, and for pipes and fittings above that diameter, through a sieve not exceed­ing 3/4 inch square.

 7. COMPOSITION AND PREPARATION

a) Concrete – The concrete for pipes and fitting made of normal or rapid-hardening cement shall be composed of one par by volume of cement (based on a density of 90 lbs per cubic foot for normal setting and 80 lbs. per cubic foot for rapid-hardening cement) and not more than four parts by volume of aggregate. The whole shall be throughly mixed to gether first in a dry state and afterwards with a proper proportion of clean water to ensure maximum density, the mixing being done in a efficient manner preferably by a mechanical mixer.

b) Water and Consistency – The water shall be clear and free from deleterious matter and in no case shall the water cement ratio exceed 0.55 by weight. Frequent slump test shall be carried out to ensure that the required consistency of mix shall be maintained throughout the work and the slump shall be the same as that of the concrete used for the pipe tested in accordance with the type-test specified in clause 24 (b) and accepted at satisfactory. Slump test shall be carried out in accordance with the method described in the Appendix ‘C’.

8.  CONCRETE TO BE USED FRESH –
The concrete shall be used as soon as possible after being mixed and no material which has begun to develop a set shall be used in the work. After the concrete has been placed in the mould and consolidated either by bumping and rolling or by spinning it shall not be disturbed during the period of setting.

9. CURING.-
Concrete after placing, shall be protected during setting and the first stages of hardening from harmful effects of sunshine, drying winds and cold and also from running or sur­face water and from shocks. The pipe thereafter shall be removed from the mould and kept submerged in pure clean water for at least one week The pipes may then be removed from the tank and kept wet under suitable conditions for another one week

10. COVER AND LAPPING OF REINFORCEMENT.-
The cover of concrete to all reinforcement shall be at least equal to the size of the aggregate plus 1/16 inch with a minimum of 3/4 inch. In case of pipes made by the centrifugal process, however, a minimum of 1/2 inch cover shall be allowed. All reinforce­ment shall be accurately placed and means shall be provided for maintaining its position during manufacture: The main rein­forcement, if necessary. may be lapped or welded. The strength of such joints shall be equal to the strength of the bars used in the cage.

11. MOULDS AND METHOD OF MANUFACTURE.-
The moulds and method of manufacture shall be such that the form and dimensions of the finished work are accurate, the surface and edges clean and true, the ends square with the longtiudinal axis and the concrete dense and homogenous. Tamping, pressure, vibration, bumping and rolling, centrifugal action or other effective method shall be used to consolidate the material.

12. NOMINAL INTERNAL DIAMETER ·THICKNESS AND WEIGHT OF DIFFERENT CLASSES OF PIPES.-
The nomi­nal internal diameter thickness and weight of different classes of pipes shall be in accordance with Appendix ‘B’.

13. PERMISSIBLE·DEVIATION ,FROM NOMINAL INTER­NAL DIAMETER.-
The internal diameter of any pipe through­ out the effective length shall no where deviate from the nominal internal diameter by more than 1/8″ upto and including 18 inch diameter pipes and by 1/4 upto and including 48 inch diameter pipes.

14. PERMISSIBLE VARIATION INTHICKNESSOFWALLS.­
The ridial thickness of the wall of a pipe or fitting shall nowhere vary by more than 1/16 inch upto & including pipes ranging from 3 inch diameter to 18 inch diameter and by 3/32 inch upto and including pipes .ranging from 20 inch diameter to 36 inch diameter and by 1/8 inch upto and including pipes ranging from 38th inch diameter to 48 inch diameter. The above varia-tions may be either plus or minus.

l5. STANDARD LENGTH OF PIPES. –
The standard legnth of ‘A’ and ‘B’ Class pipes shall be as follows:-

a) Pipes upto and including 10″ bore = 6 feet.

b) Pipes of 12 inch and over = 8 feet.

16. INTERNAL DIAMETER OF SOCKETS AND COLLARS.­
The internal diameter of the socket or collar of a pipe shall be such that the mi~imum clearance between the inner surface of the socket or collar and the outer surface of the spigot of the entering pipe, when the two pipes are placed concentrically, shall be not less than the amount set below for the appropriate diameter of the pipe. 

Nominal Internal Diameter of Pipes Minimum Clearance b/w spigot and socket or collar Normal Internal Diameter of Pipes Minimum clearance b/w spigot and socket or collar
4     ’’ 3/8     ” 21 inches24    ”27    ” 5/8 inches3/4    ”3/4    ”
6     ” 3/8    ” 30    ” 3/4    ”
8     ” 3/8    ” 33    ” 3/4    ”
9     ” 3/8    ” 36    ”
10   ” 3/8    ”
12   ” 5/8    ” 42    ” 3/4    ”
15   ” 5/8    ”
18   ” 5/8    ” 48    ” 3/4    ”

 

17. STANDARD LENGTH OF COLLARS.-
The standard length of collars for Class ‘A’ and ‘B’ pipes shall be as detailed. here under:-

Nominal Internal Diameter of Pipes Length of Collar Normal Internal Diameter of Pipes Length of Collar
4     ’’ 6   ” 21 inches24    ”27    ” 9 inches9    ”9    ”
6     ” 6   ” 30    ” 9    ”
8     ” 6   ” 33    ” 9    ”
9     ” 6   ” 36    ”
10   ” 6   ”
12   ” 6   ” 42    ” 10    ”
15   ” 8   ”
18   ” 8   ” 48    ” 12    ”

18. WALL THICKNESS OF COLLARS AND SOCKETS.-

The thickness of the wall of a collar or a socket shall be the same as that of the appropriate diameter of pipe in the respective class.

19. STEEL REINFORCEMENT.-
The quantity of steel rein­forcement required for ‘A’ and ‘B’ Class pipes and Collars shall be as detailed in Appendix ‘A’.

20. MATURING OF PIPES AND FITTING.-
Unless otherwise Authorised in writing by the Purchaser no pipes or fittings shall be supplied under this specification until they have been allowed to mature under suitable condition for a period of not less than two weeks.

21. FACILITIES FOR SAMPLING AND TESTING.-
The purchaser or his representative shall at all reasonable times have free access to’ the place, where the pipes and fittings are manu­factured for the purpose of examining and sampling the mate­rials pipes and fittings and for supervising the testing and mark­ing, if necessary, of the pipes and fittings. The manufacturer shall provide free of charge every facility and all labour required for such examination, sampling, inspection, testing and marking before delivery and .shall provide and maintain in good working order suitable convenient and accurate apparatus for testing sample pipes and fittings. Failing facilities at his own works for  marking the prescribed tests, the manufacturer shall bear the cost pf carrying out the tests elsewhere.

22. PIPES AND FITTING SUPPLIED FROM STOCK.-
When pipes and fittings made to this specification are supplied from stock the manufacturer shall, if so required, furnish to the purchaser a certificate that the pipes and fittings have been made in all respect in accordance and comply with the requirements of
this specification. Should the Purchaser so desire, any or all of the tests herein specified shall be made by the manufacturer, and if the pipes or fittings pass the tests they shall be accepted, provided that they comply with the other requirements of this specification, or in  the event of failure to pass the tests, they may be rejected.

b) Crushing Test.- Each selected pipe shall be placed centrally between, and with its longitudinal-axis parallel to, two hard unvielding bearers of 6 in. width, with rubber packing 6 in. wide and 1 in. thick between the bearers and the pipe.

The bearers shall extend the full length of the pipe. The load shall be steadily and uniformly applied, starting from zero, at a rate not exceeding 112 lbs. per ft. length of pipe per 10 seconds. The pipe shall support without any sign of failure for at least 1 minute a minimum toad of 1350 lbs. per. foot of length.

24. SAMPLE FOR TESTING.-

a) Number of pipes or fittings (where applicable) to be selected for the hydraulic test. From each batch of pipes or fittings submitted for inspection, the Purchaser or his repre­sentative may, if he so desires, select pipes or fittings for the hydraulic test specified in clause 24 (a) .and 25 (b) as

Two per cent of the pipe or fittings when the batch comprises 500 pipes or fittings or less, and if the batch comprises more than 500 pipes or fittings, 2 per cent of the first 500 and one pipe or fitting from every 100 or part thereof beyond this number.

Should all the pipes or fittings selected, pass the test the whole of the pipes or fittings comprising the batch shall be deemed to comply with this test. If one pipe or fitting fails,
the purchaser or his representative may select from the same 
batch a further similar number for testing, and if all such further pipes or fittings comply with the test the whole of the pipes or fittings comprising the batch shall be deemed to comply with this test. If any of the pipes or fittings selected for the re-test fail, then the Purchaser or his representative may require all of the remaining pipes or fittings to be tested, and in that event only such as ocmply with the-test shall be accepted.

b) Number of pipes or fittings (where applicable) to be selected for the absorption test. From’ each batch of 100 pipes or fittings or less number submitted for inspection,
the purchaser or his representative may, if he so desires, select one pipe or fitting for the absorption test specified in clauses 24(b) and 25(b). If this pipe or fitting fails the Purchaser or his representative may select from the same batch two further pipes or fittings for testing, and if both comply with the test the batch represented shall be accepted, but if either fails the whole of the batch represented may be re­jected.

c) Nurnber of pipes to be selected for the crushing test. From each batch of pipes submitted for inspection the Pur­chaser or his representative may, if he so desires, select pipes for the crushing test specified in clause 24 (c) as follows :-

Two per cent of the pipes, when the batch comprises 500 pipes or less, and if the batch comprises more than 500 pipes, 2 percent of the first 500 and one pipe from very 100 or part there of beyond this number. Should all the pipes selected pass the test the whole of the pipes comprising the batch shall be deemed to comply with this test. If one pipe fails the Purchaser or his representative may select from the same batch a further similar number for testing, and if all such further pipes comply with the test the whole of the pipes comprising the batch inclu­ding those which have passed the test, shall be deemed to comply with this test. If any of the pipes selected from the re­-test fail, then the whole of the batch represented may be re­jected.

APPENDIX “A”
SCHEDULE OF REINFORCEMNT OF STEEL
FOR PIPES & COLLARS

STEEL REINFORCEMNT FOR PIPES

 

STEEL REINFORCEMENT OF COLLARS

SPIRALS STRAIGHT

(RODS)

  SPIRALS STRAIGHT

(RODS)

Diameter Gauge Weight Gauge Weight Gauge Weight Gauge Weight
4   “ 10 Swg 0.62 lbs 8  Swg 0.87 lbs 10  Swg 0.10 lbs 8  Swg 0.14 lbs
6   “ 10 Swg 0.82 lbs 8  Swg 0.87 lbs 10  Swg 0.16 lbs 8  Swg 0.14 lbs
8   “ 10 Swg 0.95 lbs 8  Swg 0.87 lbs 10  Swg 0.21 lbs 8  Swg 0.14 lbs
9   “ 10 Swg 1.10 lbs 8  Swg 0.87 lbs 10  Swg 0.24 lbs 8  Swg 0.14 lbs
10 “ 10 Swg 1.30 lbs 8  Swg 0.87 lbs 10  Swg 0.27 lbs 8  Swg 0.14 lbs

 

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