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In 1884 the wood pavements in London consisted generally of blocks 3 inches wide by 6 inches deep by 9 inches long, although the dimensions of length and depth varied somewhat.

Swedish deal blocks laid on concrete with a cushion-coat of asphalt cost $3.08 per square yard and had an average life of seven years and cost $0.209 annually for repairs. Creosoted blocks, lime joints, cost $2.95 per square yard, with an average life of eight years, and cost $0.204 per year for repairs. Creosoted blocks with asphalt mastic joints cost $3.55 per yard, with an average life of eight years, and cost $0.24 per year for repairs. Pitch-pine blocks cost $2.91 per square yard, with cement joints, with a life of eight or nine years, and were maintained at an expense of $0.088 per square yard per year for repairs. The life of these foreign pavements is estimated for the traffic standard of 750 tons per yard of width per day.

The cost of repairs varies very much with the method of making them. A contract was made to keep Piccadilly and part of Kings Road in repair for fifteen years for 3s. per yard per year, when the engineer estimated that its cost would not be more than 2s. The annual cost per square yard for a plain deal, spread over fifteen years, ran 1s. 33d., with a traffic of 279 tons, to 3s. 2d. for improved pitch-pine, with a traffic of 558 tons per yard per day. These figures were made in 1884. In 1893 a portion of the Euston Road was paved with wood-63 feet with yellow deal, 62 with Karri, 49 with yellow deal, and 63 with Jarrah. After three years' time the wear was found to be inch on Jarrah and Karri, and 13 inches on the deal. From observations taken, the traffic was found to be 575,544 tons per yard of width per annum. On another portion of the same road the wear was inch per annum with a traffic of 411,318 tons.

Tottenham Court Road, which was paved with Jarrah blocks, showed only inch of wear after three years, with greater traffic than Euston Road, and on the Westminster Bridge Road after nearly seven years of wear the Jarrah blocks had worn from 11/16 to 11 inches, with a traffic of from 233 to 334 tons per foot of roadway in twelve hours.

Table No. 70 gives information relative to hard-wood pavements in London.

filled with asphalt, sand, or gravel. In some cases, however, the row of blocks next to the curb was left open until the greatest amount of expansion had taken place, and then filled in.

The kind of wood used in London at that time was generally Swedish deal, and the blocks were generally laid without any chemical treatment, as that was considered of doubtful advantage, as they wore out under traffic rather than failed from decay, and it was not thought that creosoting or similar treatment would benefit the wearing qualities.

In 1874 Mr. Wm. Haywood made an extensive report to the Commissioners of Sewers of London upon the comparative merits of wood and asphalt pavements. At that time there were but

12,238 square yards of wood pavement and 30,802 square yards of asphalt, quite a portion of the area previously laid with wood having been replaced with asphalt.

In a table which he presented at that time he gave the actual life of wooden pavements that had been laid at different times since 1841 as varying from five years and five months to nineteen years and one month. The pavement having the longest life, strangely enough, was the first one laid of those in the table. The average cost per square yard during life, including repairs, varied from 1s. 54d. to 3s. 4d., which last pavement had a life of twelve years and three months. He gave the average life of the pavements in the three streets of the largest traffic as nine years, and those of the least traffic as eleven years and three months. His conclusions on the whole were more favorable to asphalt than to wood, although the experience with asphalt at that time extended over a period of only five years, but later experience has justified his conclusions. London at the present time is using wood as a paving material practically for the same reasons as those given for Paris-because it is less noisy than stone and less slippery than asphalt.

On London Bridge, King William Street, blocks wore 25 inches in three years and two months, the traffic being 12,000 vehicles per yard for twelve hours. Mr. Haywood estimated in general that the wear of wooden pavements would be from 2/10 to 3/10 inch per year, under traffic of from 300 to 660 vehicles per yard for twelve hours.

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In 1884 the wood pavements in London consisted generally of blocks 3 inches wide by 6 inches deep by 9 inches long, although the dimensions of length and depth varied somewhat.

Swedish deal blocks laid on concrete with a cushion-coat of asphalt cost $3.08 per square yard and had an average life of seven years and cost $0.209 annually for repairs. Creosoted blocks, lime joints, cost $2.95 per square yard, with an average life of eight years, and cost $0.204 per year for repairs. Creosoted blocks with asphalt mastic joints cost $3.55 per yard, with an average life of eight years, and cost $0.24 per year for repairs. Pitch-pine blocks cost $2.91 per square yard, with cement joints, with a life of eight or nine years, and were maintained at an expense of $0.088 per square yard per year for repairs. The life of these foreign pavements is estimated for the traffic standard of 750 tons per yard of width per day.

The cost of repairs varies very much with the method of making them. A contract was made to keep Piccadilly and part of Kings Road in repair for fifteen years for 3s. per yard per year, when the engineer estimated that its cost would not be more than 2s. The annual cost per square yard for a plain deal, spread over fifteen years, ran 1s. 3 d., with a traffic of 279 tons, to 3s. 2d. for improved pitch-pine, with a traffic of 558 tons per yard per day. These figures were made in 1884. In 1893 a portion of the Euston Road was paved with wood-63 feet with yellow deal, 62 with Karri, 49 with yellow deal, and 63 with Jarrah. After three years' time the wear was found to be inch on Jarrah and Karri, and 13 inches on the deal. From observations taken, the traffic was found to be 575,544 tons per yard of width per annum. On another portion of the same road the wear was inch per annum with a traffic of 411,318 tons.

Tottenham Court Road, which was paved with Jarrah blocks, showed only inch of wear after three years, with greater traffic than Euston Road, and on the Westminster Bridge Road after nearly seven years of wear the Jarrah blocks had worn from 11/16 to 11 inches, with a traffic of from 233 to 334 tons per foot of roadway in twelve hours.

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Table No. 70 gives information relative to hard-wood pavements in London.

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Hardwood paving has not been sufficiently long in use to judge accurately as to its life under varying conditions, but generally it would appear to last about twelve years. The Council in granting loans of this kind allows a period of ten years for the repayment thereof. For heavy traffic the material is likely to be extensively used, although in several districts Baltic deal is still employed in preference, the average cost of the latter being $1.68 per square yard, and the life from five to eight years.

NOTE. The above information concerning hardwood pavements in London was furnished the author by the Clerk of the Council in 1899.

London Specifications.

Hard-wood Pavements.-The surface is to be laid to such curvatures, currents, and inclinations as may be needful to enable the water to run off with the best selected Karri or Jarrah blocks 3" x 9" x 5" deep, sawn true and free from shakes and gum-holes and thoroughly seasoned. The blocks are to be laid close with the grain, vertical, in transverse rows at right angles with the channel

courses; the channel to be formed of three rows of blocks laid parallel with curbs. These channel-courses are to be dipped in a mixture of boiling tar and pitch in the proportion of four to one, and laid close and well in advance of the general work, an expansion-joint one inch wide to be left next to the curbs and to be filled in with sand. A mixture of boiling tar and pitch mixed in the proportion of five to one is to be poured over the entire surface of the wood pavement and worked into the interstices between the blocks and cleaned over with squeegees; the surface is then to be floated with cement grout brushed over same until every interstice is perfectly filled up, and a coating of clean, sharp Thames sand to be immediately thereafter spread over the surface.

Soft-wood Pavements.-No tender for blocks less than six inches in depth will be accepted. The blocks are to be of the best yellow deal and are to be creosoted;—the creosoting used is to be of the best creosote oil free from adulteration and heated to a temperature of 220° Fahr., and forced into the blocks under a pressure of 144 lbs. to the square inch, the steam generated being first withdrawn from the creosoting-cylinder by means of an air-pump. The creosote as described is to be forced into the blocks as specified to the amount of 12 lbs. to the cubic foot of timber, which must be ascertained by weighing the wood before putting it into the cylinder and weighing it after it has been taken out. The blocks are to be laid on the concrete foundation with grain vertical, in transverse rows at right angles with the channel-courses, the joints to be close. The channels are to be formed with three courses of blocks laid parallel with the curbs,-an expansion-joint at least one inch wide being left next the curbs. The joints of the pavement are to be grouted and filled up solid with a mixture of blue lias lime and sand, and the surface to be dressed with a layer of fine hoggin or gravel.

The Surveyor for the Board of Works for the Strand District, London, says (Feb., 1900):

"The system of laying wood pavements during the past twenty years has little altered, and the best pavement is considered to be the soft wood [Baltic timber] creosoted and laid with small joints. run in with bitumen and grouted with Portland cement and sand,

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