CO882-(3-4) — Page 677

PUBLIC RECORD OFFICE

minimmilu

Reference :-

CO. 882

4PUBLIC RECORD OFFICE, LONDON

ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC- COPYRIGHT PHOTOGRAPH-NOT TO

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cost of these piers should balance, it is necessary that the price for the masonry in the Pérádeniya bridge per cubic yard should have been 43 of that in the piers on the Nánu-oya railway, or, in other words, that its cost should not have exceeded Rs. 15:05 per cubic yard.

28. D.-Culverts. The principal alterations suggested for the consideration of the consulting engineer are the substitution of dry masonry for masonry in mortar in the case of flat-topped culverts; for open culverts, which are exposed to the direct vibrations of passing trains, and for arched culverts adopted for the larger streams, I have estimated I have set down the price for dry masonry at for masonry in mortar as heretofore. Rs. 11 instead of Rs. 13 per cubic yard, thus allowing Rs. 2 per cubic yard to represent the value of the mortar.

The decrease in formation widths, referred to in para. 13 of this report, has naturally resulted in a corresponding decrease in the length of each culvert.

I have substituted drop walls at both ends to all classes of culverts as upon the Nanu-oya railway, in lieu of the pitebing originally provided for; the cost of this alteration has been duly allowed for.

I have dispensed with coping in all cases for which a special price of Rs. 32 per cubic yard was arranged with the contractors for this railway, and have rubstituted pointing in cement to the exposed joints in the top courses of all walls built in mortar; for this the price agreed upon with the contractors for this line of Rs. 1 per superficial yard has been allowed. I do not consider that any injurious effect can result from the omission of coping, as in the country traversed by the Haputalé railway, frost, except hoar frost which disappears immediately after sunrise, is unknown, and this is, I think, neither severe nor long enough continued to produce any appreciable damage to the work.

I have also after careful examination of the ground revised the culverts on the first six miles of the line,* and for the larger culverts have adopted the enlarged section of wing walls used upon this railway.

29. The nett result of all these alterations has been a reduction in the estimate of Rs. 74,048'55, and of this sum I consider Rs. 34,535 80 represents the saving due to the use of dry masonry instead of masonry in mortar.

30. Before leaving the subject of culverts, I would remark that, as in the case of bridges, I should on no account recommend the adoption of masonry in any degree inferior to that specified for the Nanu-oya railway. The dry masonry especially, should the adoption of this class of work be sanctioned by the consulting engineer, must be very carefully built.

31. E.-Retaining Walls. In this item, which amounts to Rs. 688,073·80, I have made no alteration, but have retained the sum set down for it in Estimate No. 4.

The experience gathered upon the Nánu-oya railway, where the expenditure to 31st March last has been only Rs. 229,605-04, or 53-10 per cent. of the scheduled amount of Rs. 432,394·20, leads me most confidently to anticipate that in construction a very large saving under this head, probably amounting to Rs. 200,000 or more, can be effected by small deviations of the line; but as your instructions did not, as I understand them, include the setting out of these deviations, which would necessitate the most careful study of the ground at each place where walls are scheduled, and which, owing to the absence of any house accommodation along the route, would have occupied a long time and involved a very large expenditure, I have preferred to leave the amount originally set down unaltered, the more especially as a margin to cover excess expenditure and unforeseen contingencies under other heads of my estimate is thus conveniently afforded.

32. It is perhaps desirable to retnark that upon the steep sidelong ground, having an inclination of from 30° to 45°, or even steeper, where these walls invariably occur, a lateral deviation of the line of only a few feet, which can be easily made, often in a few hours, when the construction of the line is begun, without delaying the work, will, where such deviations are practicable, as they in many cases undoubtedly are, have the effect of largely reducing the contents of a wall, or even of rendering it unnecessary.

33. F.-Permanent Way. The principal alterations suggested under this head are the reduction in depth of ballast which, measuring from the top of the rail to formation level, I propose to be I foot 6 inches, instead of 2 feet as upon this railway, and the use

898 para 7 of Consulting Engineer's letter to Crown Agents of 10th December 1879, Sessional Paper VI. of 1980.

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of hardwood sleepers alternately with creosoted sleepers upon sharp or guarded curves only, the rest of the line being laid with creosoted sleepers throughout.

34. The first of these alterations, by which the nett quantity of ballast is reduced to 1.50 cubic yard, or say, to allow for packing, trimming and waste, to 180 cubic yard lineal yard, equal to 3,168 cubic yards per mile, as compared with 4,400 cubic yards formerly provided for, has resulted in a saving of Rs. 35,960.

per

35. The depth of ballast now proposed gives at the centre line a thickness of 8 inches under the sleepers, which under the rail upon the straight portions of the railway is somewhat increased owing to the transverse slope given to formation. The least depth of ballast under the sleepers at any point of their length is at their depressed ends upon those portions of the line where, owing to the occurrence of sharp curves, the maximum superelevation of 6 inches is given to the outer rail; but even in these extreme cases this depth is 6 inches, while under the sleeper at the centre of depressed rail it is 7 inches, and this depth will I trust be deemed sufficient by the consulting engineer for efficient drainage, taking into account the transverse slope given to formation level and the use of excellent, clean, hard, broken stone ballast, to both of which I attach great importance and on which I should, as on the Nánu-oya railway, rigidly insist.

Some economy might have doubtless been effected by retaining the same depth of ballast as upon the Nánu-oys railway, but by allowing the lower six inches in depth to be of stones of larger dimensions; but the saving would not, I fear, be very large, as it would be still necessary to break the stone by sledge hammers to its required size, and I hesitate to recommend this alternative, as I fear that if carried into effect much inspection and difficulty would be entailed, especially if the work were done by contract, in getting the top ballast, which for packing must be of small-sized stones, broken to the required dimensions.

may mention that the minimum depth of ballast upon Prussian railways under the sleepers, as given by Mr. Molesworth, is 8 inches.

Upon the West Shore railway in the United States, referred to in a preceding paragraph of this report, the depth of ballast is stated to be 1 foot 6 inches.

36. Further reductions in the cost of the permanent way in Ceylon have been effected by the omission, or shortening to a slight extent, of some of the sidings at the roadside stations, (this will be referred to under the heading of stations), and also by the substitution upon straight lines and flat curves of creosoted for bardwood sleeper; but the effect of this latter alteration has been to some extent neutralized by an increase in the cost of the Baltic or creosoted sleepers from Europe, consequent upon the larger number of them required. This point will be treated upon hereafter.

87. On account of my unfavourable experience of the duration of hardwood sleepers, I would willingly recommend their being dispensed with altogether, even upon sharp curves, if some other efficient means could be devised for maintaining the gauge, which is on those portions of the line always more liable to spread, and where the additional resistance offered by the hardwood sleepers to this tendency is, I think, very valuable.

38. In pricing out my estimate for permanent way, I have corrected a manifest discrepancy of the contractors in pricing out the schedules for the Nanu-oya railway. It will be observed on reference to page 148 of the specification, that where guarded rails are used the contractors' prices for the storage and transport of the main rails and their fastenings are respectively Rs. 598-75 and Rs. 100 per mile; while upon page 149 the amounts set down for these items are doubled. I have considered, as I think I am entitled to do, that the lesser prices represent the value of the work, and have, therefore, calculated the present estimate accordingly.

39. The nett result of all these alterations has been to effect a total saving of Rs. 150,855-22 upon this item.

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40. G.-Switches Crossings, and Guard Rails. The reduction in this item of Rs. 3,080 is solely due to the less number of switches and crossings required in con- sequence of the alterations made in the station yards.

41. H.-Fencing, I do not propose to fence any part of the Haputalé railway, except perhaps for a short distance at Haputalé station, and also at a few other points if required for the safety of the public.

have allowed Rs. 300 for the erection only of one mile of fencing, the materials for which can be supplied by Government out of those remaining unused, imported for this railway. The saving, therefore, under this head amounts to Rs. 19,700.

* Proceedings, Inst. C.E., vol. lxxvii, page 248.

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