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of adjacent property; and the Contractor shall take down and remove all plant and materials as occasion may require, or when ordered so to do by the Engineer. Only the necessary amount of plant and materials will be allowed on the job.
Wood Blocks 2. The whole of the timber, both soft and hard, to be good sound timber, well seasoned, and sufficiently matured. No block to contain more than 10 per cent. of sap wood, and all blocks to be free from shakes, waney edges, warps, sneaps, large, loose, or dead knots, or other defects, and to be sawn square and true.
Description of Timber 3. All soft wood blocks shall be cut from good quality pine deals from Baltic, White Sea or Archangel Ports.
Size of Wood Blocks 4. No wood blocks shall be less than 8 inches or more than 912 inches in length, or less than 3 inches or more than 312 inches in width. Each block shall be exactly the depth ordered, as no allowance will be made for the saw cut.
Creosoting Wood Blocks 5. The whole of the soft wood blocks used in the work shall be thoroughly impregnated with pure creosote oil, free from all ammoniacal water, and containing not less than 8 per cent. of tar acids. The wood blocks shall be creosoted by Boulton's or Bethell's process, the temperature of the oil in the cylinder being not less than 220° F., the cylinder to be first exhausted to a vacuum equivalent to 20 inches of mercury, and the creoscte then forced into the blocks to the extent of not less than 10 lbs. to the cubic foot of timber. The quantity of creosote in the blocks shall be ascertained by weighing 50 blocks of each charge in the white, and after creosoting, the same 50 blocks shall be wiped, and all moisture adhering to their surfaces removed. The blocks shall then be weighed, and the difference between the weight so ascertained and the weight of the same blocks in the white shall be taken as the weight of the creosote oil absorbed.
Asphalte 6. The rock asphalte shall be a natural bituminous limestone rock of the best quality, without the addition of any other substance whatever, ground to a fine powder, heated to the proper degree, and thoroughly compressed with hoto rammers, or rolled to the uniform thickness specified.
Each Contractor shall send with his tender a description of the asphalte rock he proposes to use, and must state the place of its origin.
Cement 7. The cement shall be the very best Portland, manufactured solely from chalk and clay of the best possible quality, free from stones, hard lumps, or any foreign matters, and in entire accordance with the British Standard Specifications for Cement, copy of which may be seen at the Engineer's Office at the City Hall.
Ballast. 8. The ballast shall be from the River Thames, and shall be clean and free from mud, clay, or loam. No stone shall be of larger size than will pass through a 2-inch ring. The proportion of sand to stones shall be to the approval of the Engineer, and all ballast is to be screened through a 18-inch mesh screen to remove any excess of sand and fine material. The screening is to be done on the site of the work, and the excess of sand screened from the ballast may, with the approval of the Engineer, be used for floating.
Sand 9. The sand shall be clean and sharp, and free from mud, loam, etc., and capable of passing through a sieve with 64 meshes to the square inch.
10. All concrete shall be composed of six parts of Thames ballast to one part Portland cement, or, subject to the approval of the Engineer, of four parts macadam or other broken stone (consisting only of such portions as are retained on a 1-inch sieve), two parts clean sharp sand, and one part Portland cement. The various proportions of material shall be ascertained in all cases by actual measurement in boxes of the proper capacity. All concrete shall be mixed on a platform of boards or planks, so as to ensure the exclusion of loamy or foreign matter. The surface shall be finished off to a smooth face with a floating about 1 inch in depth composed of sand and Portland cement in the proportion of three of sand to one of cement. The total thickness of concrete foundation and floating shall in no case be less than 9 inches over the whole area of the street (from kerb to kerb). Not more than one cubic yard of concrete shall be mixed at one time on each board, and no concrete when it has once commenced to set shall be “knocked-up" again for re-use. The materials shall be turned over at least five times, viz.: twice in a dry state, once when being watered, and twice wet. The Contractor shall make his own arrangements with regard to the necessary water, and it shall be applied through a rose.
Fine Concrete 11. Fine concrete for making up to receive asphalte shall be formed of three parts of clean crushed ballast, to pass a 34-inch sieve, one part sand and one part Portland cement.
Rcmoval of Old Paving Stones 12. The Contractor shall carefully remove the whole of the granite paving stones in carriageways and in channels and crossings of macadamized roads, and any concrete which may be thereunder, as directed by the Engineer, and cart the same away at his own expense. Such paving stones shall become the property of the Contractor (except as may be otherwise specified), who shall make a proper allowance for the same in his estimate.
The old concrete under pitching may, if approved by the Engineer, be broken up and re-used in the new concrete, but if not so approved it shall be removed from the site by and at the expense of the Contractor.
Removal of Existing Blocks 13. In the case of roads at present paved with wood or Sanitary blocks, which it is intended to re-pave only, the Contractor shall remove the existing pavement and cart it away, making a proper allowance for same in his estimate. In the case of the Council requiring any of the old blocks, the Contractor shall sort out, clean and temporarily stack as directed by the Engineer, and cart to any street or depot in the City, for the sum of 8s. per thousand blocks, as many sound blccks, of the depth of three inches and over in the case of wood and two inches and over in the case of Sanitary blocks, as the Engineer may require, up to 20 per cent. of the area to be re-paved.
Preparing and Floating Existing Foundations 14. The Contractor shall after the removal of the old paving thoroughly sweep and clean the surface of the existing concrete, and, if necessary, score it to form a ey for floating He shall hack off defective floating and reduce floating or concrete when necessary for camber or fall. He shall first, however, carefully examine the existing foundation and as directed by the Engineer cut out all
portions thereof where concrete is wanting or defective and replace with new concrete at least 6 inches in thickness. Where the existing concrete is found to be sunk, he shall excavate trial holes, and if required by the Engineer remove the sunk concrete, consclidate the subsoil by ramming and watering, make up with hard core to required level, and lay 6 inches of concrete. The whole of the foundations shall then be properly floated, if so ordered by the Engineer, to approved cambers and falls, with Portland cement and clean sharp Thames sand, in the proportion of one part of Portland cement and three parts of sand when and as mixed together.
15. The Contractor shall excavate to the depth required by the City Engineer to form foundation and pavement in the whole of the roadways in which new wood, asphalte or other paving is to replace existing macadam or pitching; and such of the old macadam as the Engineer shall approve may be used for concrete, in the proportion herein before specified, and the surplus shall become the property of the Contractor, who shall at once remove the same at his own cost. It is the intention of this Specification that the Contractor shall perform all the excavation work required to form the new roadway at the new levels at the price per super. yard quoted, and no claim can be recognized for extra excavation by reason of a variation in the street levels.
The excavation shall be very truly finished to the exact cross-sections and cross falls and longitudinally so as to give the channels a true and even incline towards the gullies, and to show a sufficient and proper depth of kerb, which shall not in any case be less than 3 inches.
New concrete shall be laid in each case to the thickness specified in the Schedule.
Setting of Foundation
16. After the foundation has been finished, the blocks or asphalte shall not be permanently laid upon it for at least six days without special permission of the Engineer, during which time the concrete shall be protected from the weather and any injury, but wood blocks shall be "headed" up as provided in the next clause.
Laying Wood Blocks
17. All pavements composed of wood blocks shall be laid as follows: Two courses of hand-dipped blocks shall be laid on each side of the road parallel to the kerb, and a space of from 1 to 2 inches, if required by the Engineer, shall be left between the kerb and the wood blocks, to allow for expansion, such space to be filled in with clean puddled clay, or other approved material. The pcrtion of the road between these courses, shall be laid with blocks at right angles to the direction of the road, except at the intersection of other roads, where the blocks shall be laid diagonally as directed. After the concrete and floating ccat has been in position three days, the wood paving blocks shall be "headed up" on the foundation and shall so remain for three further days before the block are "laid" permanently. No blocks shall be laid until they have been so "headed up" for three days. All pavements shall be laid so as to leave as little space as possible at the sides and ends of the blocks, and on completion a mixture of boiling pitch and creosote oil in approved proportions shall be poured over the whole surface and well forced into the joints, and scraped off with wooden or rubber squeegees, the joints being thoroughly filled. The pavement shall then be finished with fine sand and cement grout in equal proportions brushed over, and with a top dressing of approved gravel to pass a 1-inch mesh free from sand. Care shall be taken that not more than sufficient grout is used; in the event of it "spewing" in hot weather, or working up under traffic, the Contractor shall be required to remove the surplus and cleanse the road surface at his own cost.
Hard-wood blocks (Jarrah and Karri) shall be hand-dipped on one side in an approved mixture of boiling pitch and creosote oil immediately before laying, and shall be laid with as tight a joint as possible, the paving afterwards being grouted over and finished off in all respects as above specified.
No wood paving of any kind is to be grouted over without special written permission until 24 hours have elapsed after the completion of the laying of the blocks in that particular section.
Combined Strip Paving 18. Combined strip paving shall consist of creosoted pine paving supplied, prepared and executed in every way of the character and in the manner previously specified, with this exception, that every alternate transverse course shall be a line of plain Jarrah wood strips, each strip the same depth as the pine paving, and consisting of blocks not greater than 112 inches thick and 9 inches long, and not less than 136 inches thick and 8 inches long (i.e., the trai verse courses of Jarrah and pine shall be equal in number).
These thin Jarrah blocks shall be laid dry in the first instance, and after the paving has been examined and approved by the City Engineer each Jarrah block shall be hand-dipped in a tough mixture of pitch and creosote oil, kept hot and extremely fluid so that the lower part of each block for a depth of 3 inches from the bottom of the block is thoroughly coated with the bituminous mixture. In replacing the blocks after dipping care is to be taken to knock up the joints tightly. The paving shall be finally grouted off and finished in all respects as previously specified for laying wood blocks.
Laying Rock Asphalte 19. The rock asphalte pavement shall be laid in a workmanlike and proper manner, and shall be finished throughout its whole area the exact thickness speci. fied, and so as to make a regular and even joint with the adjoining pavement. The Contractor shall protect the new asphalte paving until it is fit to bear the traffic without injury. Where asphalte is to replace wood paving, the Contractor shall provide for fine concrete to make up the foundation to the required new level as directed by the Engineer.
Proprietary Materials 20. In case of firms tendering for the supply of proprietary materials, such as artificial asphalte, bituminous concrete, etc., they shall describe the same in the blank space in the Schedule, and give below full particulars of such materials, the manner in which they are to be employed, and the method of forming the street.
CITY OF WESTMINSTER
CITY ENGINEER & SURVEYOR' OFFICE
SHORT SPECIFICATION AND SCHEDULE OF CHARGES FOR
TRENCH REPAIRS, 1913-1914
York Footway and Granite Kerb Cutting holes in paving or kerb, etc., and fixing frame in cement where necessary; not exceeding 200 sq. in...
.$ .32 each Cutting holes in paving or kerb, etc., and fixing frame in cement where necessary; exceeding 200 sq. in..
.60 each New granite kerb 12 inches by 8 inches bedded and jointed in cement mortar. .58 ft. run New granite kerb 12 inches by 8 inches bedded and jointed in cement mortar, circular....
.66 ft. run New granite channelling 12 inches by 6 inches bedded and jointed in cement mortar......
.54 ft. run New granite channelling 12 inches by 6 inches bedded and jointed in cement mortar, circular...
.62 ft. run
.06 ft. sup.
New sandstone flags, bedded and jointed in cement mortar and pointed in
.$ .29 ft. sup. neat cement.. New artificial flags, 24 inches thick, entirely bedded and jointed in cement
.22 ft. sup. mortar and pointed in neat cement.. Taking up Yorkshire or other slab paving, squaring and relaying in cement
mortar and pointing in neat cement.. Taking up artificial flags, squaring and relaying in cement mortar and
.05 ft. sup. pointing in neat cement.. Taking up granite kerb (either flat or edge), squaring joints and relaying as
.05 ft. run specified for new kerb.. Taking up granite kerb (circular), squaring joints and relaying as specified
.05 ft. run for new kerb... Taking up granite kerb, squaring and relaying same as specified for new kerb. .19ft. run Taking up granite kerb (circular), squaring and relaying same as specified for new kerb..
.19ft. run Portland cement concrete, including excavation, cartage, etc., and laying complete to receive kerb or paving:
5.52 yd. cub. Extra only on all above items for continuous day and night work, Saturday and Sunday included..
. 10% Asphalte Footway One-inch compressed footway on new concrete foundation.
1.62 yd.su p. One-inch compressed footway on old foundation...
1.20 yd. sup. Asphalte Carriageways Two-inch compressed asphalt carriageway on new 6-inch concrete foundation...
3.12 yd. sup. Two-inch compressed asphalt carriageway on new 12-inch concrete foundation..
3.96 yd. sup. Two-inch compressed asphalt carriageway on old foundation.
1.44 yd. sup. Sett Paved Carriageways Take up and relay setts, rack, ram and grout with pitch grout.
.80 yd. sup.
.54 yd. sup. Take up and relay setts, rack, ram and grout with cement grout.
.92 yd. sup. Excavate for, provide and lay 6-inch concrete foundation..
1.76 yd. sup. Excavate for, provide and lay 12-inch concrete foundation.
1.26 yd. sup. Provide new 3 inch by 5 inch granite setts, extra only.
2.46 yd. sup. Provide new 3 inch by 6 inch granite setts, extra only.
1.80 yd. sup. Provide new 3 inch by 4 inch granite setts, extra only. Provide new 3-inch cubes.
1.62 yd. sup. Provide new 4-inch cubes.
1.82 yd. sup. Macadam Carriageways Repairs to trenches as specified, whatever the length or area of the trench
.88 yd. sup. may be, steam rolled... Repairs to trenches as specified, whatever the length or area of the trench
.80 yd. sup. may be, not steam rolled..
Wood Paved Carriageways
3.00 less viding new blocks required, etc., etc...
3.84 ) 10% Taking up roadway, but with concrete not less than 12 inches. Extra only on last two items for work carried out by night and day con
10% tinuously, Saturday and Sunday included..
BOROUGH OF BATTERSEA
Thursday, 25th September, 1913.
NOTES RE Wood PAVING
KINDS OF PAVING USED
(1) Deal or Soft Wood Creosoted These are cut from good quality third Archangel Deals to a uniform size, viz., 3 x 9 x 5 inches, that is to say the blocks are 5 inches deep when laid end-ways of the grain. The blocks, after being cut and inspected, are subjected to a process