QUEEN STREET TRAMLINES

New Zealand Herald, Volume L, Issue 15325, 11 June 1913, Page 8

QUEEN STREET TRAMLINES

PROGRESS OF REMOVAL.

BLASTING OPERATIONS.

HEAVIER, RAILS TO BE LAID.

Sixce the tramway traffic in Queen Street was stopped, the work in connection with the removal of the tramlines and their concrete bed has gone rapidly ahead. About 180 men are engaged on the work, and as most of them are at present busy in that portion of the street between Wyndham and Wellesley Streets, there is a great air of bustle about the proceedings. In places they are closely grouped, occupied with boring holes in the concrete for the reception of blasting charges, and the clatter of hammers and drills in these spots is constant. The concrete bed and the line on the west side of the street have nearly all been taken up, and a good start has been made, since the traffic -was stopped with the removal of the eastern line as well.

The whole of the concrete foundation, roughly a foot deep, and of the width of the double way, is being cleared out, exposing the longitudinal hardwood sleepers, over which the rails were laid with an intervening layer of concrete. The surface of Neuchatel asphalt is, of course, taken off first and put away . separately. The concrete has been found to be of exceptionally good quality, and very hard and tough. The drilling of the holes for the explosives, as well as the breaking up of the concrete by means of " gads" and hammers, is consequently heavy work. Since the City Council gave the contractors (Messrs. McLean Bros.) permission to use explosives the excavation has gone ahead far faster than was the case when only hand labour was available.

The holes are mad* about eight inches deep and an. inch in diameter, about a dozen going to the square yard, and the charges range from half a plug to a whole one in each hole, the whole- plugs weighing 10 to the pound. Several are fired at a time. Two men drill a hole, one holding the drilL the other striking it with a heavy hammer, and each pair of men can, make about two dozen holes a day. Roughly, 600 holes are fired each night, and the loosened concrete can be removed by 60 men in about four hours. This is a far more rapid process than that adopted when explosives were not used. The whole of the blasting will, it is expected, be finished in about a week.-

The removal of the concrete has disclosed the hardwood stringers, in excellent condition, signs of unsoundness being almost absent. These stringers were laid a few years ago upon piles, in order to provide a solid foundation for the track, which was laid originally about 11 years ago. The stringers and piles are not being interfered with beyond such trimming as is necessary to level their upper surfaces. Upon them new sleepers are being laid, and the rails will' be set directly upon the' timber instead of upon concrete. This, it is hoped, will reduce the noise which has been a nuisance in the past, and will also prevent the recurrence of a troublesome condition arising from the bedding of the rails upon the concrete. • In some places some small looseness of the rails occurred, and the constant working of the steel rail gradually ground the concrete away, and the dust, mixing with water, pumped, out and left a space below. • This defect was remedied by. pouring in. melted asphalt.

The track now being taken up is made of rails weighing 901b to the yard, but the' lines will be re-laid with 1101b rails.