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the Docks and Warehouses, where loads of 30 tons on four wheels are not uncommon, the thickness of the foundation is 8 inches, but for ordinary heavy City traffic 6 inches is the depth adopted. A cushion of fine gravel 12 inch thick is interposed between the sets and the foundation, and the joints, after being filled with dry shingle, are grouted with a hot pitch and sand mixture.

2. A similar set, but 314 inches instead of 4 inches wide, was formerly used, and much of this work is still in existence.

3. Sets 4 inches by 4 inches by 6 inches deep, laid in a similar way, are in use in a number of heavy traffic streets.

4. 314 inches by 314 inches sets, 5 inches or 6 inches deep, are largely used for somewhat lighter traffic, and afford a good foothold.

5. 4-inch cube sets, either on a 6-inch Concrete bed or on rock pitching 10 inches thick, have been considerably used for lighter traffic, e.g., on main roads in the outer districts and in side streets in the central area. The present tendency, however, is for the substitution of pitch macadam to meet the requirements of this class of traffic.

The cost of a Set pavement in Liverpcol, exclusive of the foundation, is about 10s. per square yard for 6-inch Sets, and 7s.6d, for 4-inch Cubes.

Examples of the above stone set pavements may be seen in the following places: 1. Sets 4 inches wide by 6 inches deep. Strand Street, laid in 1902. In this case as in some other places the original

foundation, consisting of a bituminous concrete, is still in use. Traffic,

313,000 tons per yard width per annum. Goree laid in 1908 George's Dock Gates laid in 1910. New Quay laid in 1901. At the narrowest part (where a widening is in con

templation) the traffic reaches 815,020 tons per yard width per annum. King Edward Street.-A new street constructed in 1904 to relieve the con

gestion cf the traffic in Old Hall and North John Streets. Traffic at pres

ent 147,400 tons per yard width. William Brown Street, gradient 1 in 18, was paved in 1904 with 6-inch by

4-inch Pwllheli Sets, a softer variety of Welsh granite, giving a better

foothold on a steep gradient than the harder stone. Another example of Pwllheli Sets may be seen opposite the Town Hall at the end of Castle Street.

An example of 6 inches by 4 inches "Widged" or Axe-dressed Sets in Dale Street opposite the Municipal Offices. 2. Sets 3 inches wide by 6 inches deep.

Chaloner Street. laid in 1891, traffic 313,000 tons per yard width per annum.
Sefton Street, laid in 1889-1891.
Water Street, laid in 1881, electric Tram-lines laid 1900, the old sets being

relaid, gradient 1 in 21. Traffic 46,300 tons per yard width per annum.
Dale Street and Castle Street, laid in 1877, Tram-lines constructed in 1900.
James Street, laid in 1890, Tram-lines constructed in 1900, gradient 1 in 21.
Victoria Street, laid in 1883.
Whitechapel in 1880.

Lime Street in 1875. 3, 4 inches by 4 inches by 6 inches deep. North John Street.-The portion between Lord Street and Victoria Street was

laid in 1972 (41 years ago), and was the first pitch-jointed set pavement laid in Liverpool. It has always taken traffic of a heavy character, which

at the present time amounts to 190,000 tons per yard width per annum. Ranelagh Street, laid in 1873 (40 years ago), the second pitch-jointed pave

ment laid in Liverpool. oid Haymarket, laid in 1883.

4. 344 inches by 314 inches by 5 inches or 6 inches deep. Lord Street, laid in 1877. Side of the road only. The old sets have lately

been relaid, in consequence of an alteration in the position of the tramlines and a widening of the footways necessitating a change of crossfalls

and levels. Traffic 132,700 tons per yard width per annum. Crosshall Street and Sir Thomas Street, off Dale Street by Municipal Offices,

laid in 1886. Foundation of bituminous concrete. Leece Street and Hardman Street, laid in 1885, gradient 1 in 19.

Traffic, 84,500 tons per yard width per annum. 5. 4-inch Sets. Mulgrave Street, Granby Street, Kingsley Road, laid in 1884, off Prince Avenue,

all on rock pitching; traffic in Kingsley Road 28,600 tons per yard width per annum, and in Granby Street 27,200 tons per yard width per annum.

B. Wood Blocks These are laid in some of the principal shopping streets and other streets, where a silent pavement is desirable. The Portland cement concrete foundation, 6 inches or 8 inches thick, according to circumstances, is worked to a smoother surface than for stone sets, and the blocks, which are approximately 9 inches long by 3 inches wide by 5 inches or 6 inches deep, are laid direct on the concrete bed with close joints, which then receive a final grouting of pitch mixture. For merly these pavements were laid with a sand cushion and wider joints filled with pea-gravel and pitch as in the case of the stone sets, and a number of examples of this construction still exist. The two principal types are:

1. Australian Hardwocd Blocks, principally for heavy traffic, but laid less frequently in recent years.

2. Red Pine Blocks, creosoted, the use of which is at present being extended.

The cost of hardwood pavement varies from 11s. 6d. to 15s. 6d. per square yard, and of softwood, from 8s. 8d. to 11s., according to prices of materials. These prices are exclusive of foundation.

Examples of wood block pavements may be seen in the following places: 1. Australian Hardwood. Leeds Street and Great Howard Street, laid in 1901, opposite the Northern

Hospital. Traffic in I eeds Street, 147,400 tons per yard width per annum, including exceptionally heavy dock and warehouse traffic up to 30 tons

on four wheels. Catherine Street, between the tram-rails, laid in 1913; and Croxteth Road,

laid in 1900. Croxteth Road traffic of a lighter character, which amounts to 87,050 tons

per yard width. 2. Creosoted Pinewood. Exchange Street East, by the Town Hall, repaved in 1913, takes heavy traffic

amounting to 240,250 tons per yard width average, largely on the Welsh

granite wheelers. Tithebarn Street, opposite Exchange Station, laid in 1912. Fenwick Street, off Water Street, paved in 1898, in the old manner, with wide

joints. A street of light traffic, amounting to 53,190 tons per yard width

per annum. Church Street, an important shopping street, and also a main thoroughfare

to the business area. Repaved in 1912 on 8-inch concrete. Previously the pavement consisted of sets, and the repaving was necessitated by settlement due to the existence of a railway tunnel beneath. Traffic

147,480 tons per yard width per annum. Bold Street, an important shopping street, with much motor and carriage

traffic, amounting to 191,650 tons per yard width per annum. Repaved in 1909. Myrtle Street - Repaved in 1913.

C. Macadam Pitch grouted macadam has been found to give most satisfactory results in streets of medium and light traffic, and is now being largely used in place of ordinary macadam, and also of more expensive pavements. It is laid to a depth of from 342 inches to 442 inches, in two layers. Welsh granite macadam is used, broken to a 217-inch gauge for the lower layer and to 11/2-inch for the top surface. Each layer is put down dry and continually rolled before and after the grouting of pitch and sand mixture has been applied, until the surface is thoroughly consolidated. The foundation is generally of hand-pitched rock, 10 inches deep as for ordinary macadam, but in some cases a bed of 6-inch concrete has been used on main roads.

Pitch macadam is also being much used as a surface covering for old boulder pavements, many of which still exist in Liverpool in old streets where the traffic is very small.

The cost of pitch macadam may be taken at 1s. per square yard per inch of depth.

Other surfaces which have been tried for streets of light and medium traffic with varying success are natural asphaltes and limestone and tar mixture.

Water-bound macadam is used in residential streets and other roads in the outer districts, and also nearer the center of the City in special cases. The thickness of the macadam surface is 7 inches, and the sizes of the stones are the same as for pitch macadam. The foundation is rock pitching 10 inches thick.

Tar-spraying has been adopted with very satisfactory results. One application per annum is found to be sufficient, and the cost is 1d. per square yard.

Examples of pitch macadam may be seen in the following places:
Princes Avenue, Princes Road.—This avenue carries a large volume of light

motor and carriage traffic, as well as some of a heavier character, the

traffic amounting to 120,000 tons per yard width per annum. The oldest sample of pitch macadam in Liverpool was laid in Princes Avenue

in 1901, near the end of Eversley Street, and has been in continuous use ever since without repair. Other lengths of pitch macadam in this

avenue were laid at various dates between 1906 and 1908. Croxteth Road E., North side, between Sefton Park Road and Parkfield Road,

pitch macadam laid in 1910. Ullet Road.-Pitch macadam was laid in 1905. Traffic 83,070 tons per yard

width per annum. Leece Street and Hardman Street.-A length of ordinary macadam is laid

in Leece Street and Hardman Street, where the gradient of 1 in 19 demands a surface with a good foothold, and is subjected to the heaviest wear, necessitating re-surfacing every 9 months. The traffic works out

at 84,550 tons per yard width per annum. Aigburth Drive and Croxteth Drive in Sefton Park and Croxteth Road E. (South side) are examples of tar-sprayed macadam. Pavements which have also been laid in Liverpool in recent years are:

(a)

Random stone pavement, and

(b) Concrete macadam blocks. (a) Random stone pavement consists of roughly dressed cubical stones 24 inches or 3 inches in size, laid by hand on a bed of old macadam or rock pitching, and gravel-jointed or grouted with pitch mixture. Cost about 28. 60. per square yard. Examples of this pavement may be seen in

Church Road W., Walton, and in Prescot Road near Black Horse Lane. (b) Concrete macadam blocks. Concrete blocks faced with large handbroken stones. They are formed in moulds 2 ft. by 1 ft. 6 in. in area, and 5 in. deep, and are left to mature for six months before being laid.

They are bedded on a concrete foundation, and the joints are filled with cement grout.

Cost 5/10 per square yard, exclusive of foundation.
Examples may be seen in

Binns Road, off Edge Lane, where they were laid in 1905, to take heavy
traffic amounting to 51,460 tons per yard width per annum, and in Sun
Street and Moon Street, where the traffic is light.

Accurate Measurement of Wear of Carriage-way Surfaces For several years it has been the practice in Liverpool to take periodical measurements to ascertain the wear of different classes of carriage-way surfaces under known conditions of traffic.

The information obtained over varying periods goes to show that the extended employment of this system in conjunction with regular observations of traffic tonnage leads to useful knowledge of the behavior and life of the various materials under different conditions of traffic.

In each of the methods adopted an accurately-machined cast-iron socket embedded in concrete of considerable area is adopted so that no question may arise as to the accuracy of the datum line.

These sockets are put down in the footway clear of the carriage-way surface altogether so that they may not be interfered with by any expansion or other alteration in the carriage-way surface.

Where the road is wide a central socket is also put down and this has been found to be a convenience, as it enables accurate measurements to be taken of each half of the road without completely stopping the traffic.

The accurately-machined surface in the socket is protected from injury by a plug which is screwed into an upper portion of the socket-casting when not required for measurement purposes.

Vertical standards are dropped into the opening in the sockets, and the ar. rangement of wires shown in the photograph is used in one case as a datum line from which the measurements are to be taken.

This apparatus—though suitable for purposes of carriage from point to point - is not on the whole found to be so convenient as the shorter straight-edge, the measurements from which can be taken very accurately and quickly.

A specially constructed tee-square, which rides on the beam and carries a vertical sliding rule provided with a Clamp and Vernier scale, is used to take the measurements, and rapid readings may be taken in this way.

CITY OF LIVERPOOL, ENGLAND.

STANDARD SPECIFICATIONS FOR PAVING STREETS

SPECIFICATION FOR HEAVIEST TRAFFIC ALONG THE LINE OF Docks

Carriageway Excavate or fill in the ground, as the case may be, to the requisite level, and remove all surplus material. Properly form and trim off the surface and thoroughly consolidate same, and then lay a foundation of not less than 6 inches of Portland-cement concrete, Corporation Standard (8 inches used where clay or other soft foundation). The paving shall consist of granite or syenite sets, 3; inches by 61 inches deep, from North Wales or other approved quarries, laid in regular, straight and properly-bonded courses, with close joints, and to be evenly bedded on a layer of fine gravel 4 inch in thickness. After the paving is laid, the joints shall be laid with hard, clean, dry shingle; the sets shall then be thoroughly rammed and additional shingle added until the joints are perfectly full. The joints shall then be carefully grouted until perfectly filled with a hot composition consisting of coal pitch and creosote oil, and finally, the paving is to be covered with } inch of sharp gravel.

Crossings The crossings shall consist of three rows of 16 x 8 inch granite crossing stones, and the remaining space shall be paved on each side of the crossing stones, to the full width of the footway, in a similar manner to the carriageway. The crossing stones shall be of granite of a quality to be approved by the City Engineer, dressed perfectly true and out of winding on the face; the sides and joints to be perfectly square and accurately dressed throughout their entire depth; the stones to be bedded in cement concrete, the joints to be filled with shingle and grouted in a similar manner to the paving. A triangular groove 1 inch wide by 1 inch deep to be formed along the upper surface of each stone. No stone to be less than 3 feet in length.

Footways The footways shall be paved with Lancashire (“Best Barns”) or Yorkshire flags of the best quality, not less than 3 inches thick. No flag to measure less than 2 feet in width nor to be of less area than 6 feet; to be solid, free from laminations, the upper surface to be true and free from windings and hollows; the joints to be squared the whole thickness. The flags to be laid on a bed of fine gravel, with close, neat joints, flushed in mortar, and in uniform courses breaking bond. The joints to be dressed after laying where necessary.

Channels The channel stones to be of granite or syenite, of a quality to be approved by the City Engineer, and to be not less than 3 feet in length. The upper surface, if not selffaced and perfectly true, must be accurately worked out of winding, the bed even and parallel to the face, the sides and ends truly square; the stones to be bedded on cement concrete, and the joints to be filled with clean shingle and grouted in a similar manner to the paving.

Curbs The curb stones to be of granite or syenite, straight or circular as required, 6 inches thick at top, 7 inches thick at 5 inches below, and not less than that thickness for the remainder of the depth; and not to be less than 12 inches deep, nor less than 3 feet in length; to be carefully dressed on top, 8 inches down the face and 3 inches down the back; the remainder of each stone to be hammer-dressed; the heading joints to be neatly and accurately squared throughout the entire depth.

SPECIFICATION FOR MEDIUM TRAFFIC IN CITY

Carriageway Excavate or fill in the ground, as the case may be, to the requisite level, and remove all surplus material; properly form and trim off the face, and thoro consolidate the same, and then lay a foundation of not less than 6 inches of Portland-cement concrete, Corporation Standard. The paving shall consist of granite or syenite sets 3 inches wide by 5 inches deep, or of granite or syenite, 4 inch by 4 inch cubes from North Wales, or other approved quarries, laid in regular, straight and properly-bonded courses, with close joints, and to be evenly bedded on a layer of fine gravel, 1 inch in thickness. After the paving is laid the joints shall be filled with clean, hard, dry shingle; the sets shall then be thoroughly rarmed, and additional shingle added until the joints are perfectly full. The joints shall then be carefully grouted, until completely filled, with a hot composition, consisting of coal pitch and creosote oil, and, finally, the paving shall be covered with 1 inch of sharp gravel.

The crossings, footways, channels and curbs shall be the same as specified for first-class streets.

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