ROADING SCHEME

Press, Volume LIV, Issue 16289, 13 August 1918, Page 7

ROADING SCHEME

EXPERIMENTS WITH CONCRETE

ADVOCATED

CITY COUNCIL DISCUSSION

The roading question was debated at considerable length by tho City Council laat evening. It arose out of a report by tho Works and Sanitary Committee on reinforced concrete roads, the committee supplying the following report by the city surveyor: —

til the wood-blocked, stone-pitched, and alt«d zoad surfaces at present baing constructed are built upon a concrete foundation. Iron reinforcemant is merely a strengthening 1 of the concrete foundations to enable it to carry heavy traffic on soft or bad RTOirad, particularly on ground where there 13 lik ly to be settlement. On a solid bottom the iron reinforcement would only b« an additional expense. I am not personally acquainted with any concrete road road that has not built without top of either stone pi:cbers, wood blocking, or asphalt; but with fairly light traffic I think if the concrete foundation were kept well coated with tar and grit, it should Btand well enough and would, of course, bo far chcaper than either cf tho three above-named surfaces. There would be no experiment in making a road of this kind; it is merely a part of the roads which have been made in other i\ew Zealand centres, and is putting tar and screenings in me place of an asphalt wearing top. I estimate the coat of a reinforced concrete rood witn a surface of tar and grit to i>c as follows: — X chain in length by 42ft in width between the channels 808 sq. yards £ e. d. Forming and grading of the surface per chain .. .. .. 8 0 0 Concrete, Gin thick, 51.3 cubic yards, et £1 10s per cubic yard 128 5 0 Iron reinforcement, No. 12, 308 sq. ■ yards, at 2a por sq. yard .. 3016 0 Tar and grit, 308 sq. yards, at 3d per sq. yard .. .. 3 17 0 Total .. .. 165 18 0 Concrete road constructed without, reinforcement, less item No. 3 30 16 0

£135 2 0 The city surveyor added that the most expensive tarred macadam street as yet constructed in Christchurch had not cost more than £50 per chain. Owing to the high cost or laying down this kind of road the committee said it could not see its way to recommend the Council to lay down a pieco of road in concrete as an experiment. Cr. Taylor said ho thought it was a pity that in these quiet times experiments could not be made, bccause when the war was over they would have to carry out a roading scheme. In even a small country like New Zealand, local i conditions differed, so that we could not carry out anv scheme based on Auckland or Wellington experiences. In Auckland a concrete road had been put I down without any elaborate covering, ' and had proved a distinct success. Ho would liko to see tho committee actively , keep the matter in view. A small sum | of money devoted to making experiments would) be folt sure, be money well spent. Cr. Peek agreod with Cr. Taylor. Tarred macadam would not stand motor j traffic, and other * traffic affected it, ' whereas concrete stood tho strain. A local contractor estimated the cost of ■ tho material at £1 13s, instead of £2 10s, the engineer's estimate. Nearly everything suggested in the Council was j baulked by tho city engineer as far as I work was conrerned. He would like to know . what Manchester . street cost, j which was an absolute disgrace in view ' of the money spent on it. Look at Colombo street, which was like a switch- ; back. Where scarifying was carried out and tarred macadam placed on top * how could the macadam knit? Tho j whole, trouble was in not placing down a firm foundation on top of the present , one. Ho was disappointed with the report. Cr. Ell considered that the Works Committee's proposal to send the engi- | neer to Devonport was a vory wise one. | He suggested that the engineer be sent to other places to inspect roads, includinc; the concrete, ones in Taranaki. He criticised the engineer's action in stripping the metal away in Colombo street ancTplacing the tarred macadam on top of the'soft surface left. Cr. Howard agreed with Cr. Taylor that they should have an. experimental strip of concrete road. Cr. Climio said he thought the report was very disappointing, and he felt convinced "that the majority of the Council were not in favour of it being adopted. To test tho feeling of the Council he moved that the report be, referred back to the committee. Cr. Loasby said the Council had to be advised by their executive officer, the City Surveyor. It was all very well for Cr. Peck or a contractor to say that the work conld be done for less. For an experiment they would have to put down five chains at least, which would cost £1500. Ho considered that tho time was not opportune for this. He felt satisfied that what the City Surveyor had told them was matured judgment. For the Council to pass Cr. Climie'H motion would he equivalent to a vote of censure on the City Surveyor. Cr.' Herbert agreed that the time was not opportune to spend money on experiments, and he. was not in favour of the City Surveyor going all over New Zealand to look at roads (hear, hear"), when he could secure all his information in the Council offices. Without indulging in experiments, Ist them do the thing properly, and wTien the time was opportune let them raise a l° an ' . , , . Cr.' Hay ward thought it was inadvisable to interfere with the foundations of the roads. Manchester and Colombo streets wore examples of that. On tho other hand Casliel and Tuam streets,, where the frundations had not been interfered with, were illustrations of the success of tarred macadam. He Was in favour of a small scction of concrete road being laid down ns an experiment. He cordcmned the Main South road as a disgrace, and hoped that the City Council would use its influence to secure an improvement in it. He seconded Cr. Climie's amendment. ~ , , . Cr. Williams said Christchurch streets compared moro than favourably with thoroughfares in Auckland and other places. The Mayor (Mr H. Holland) said the experiment of a concrete surface could only apply to a blind street, as it would cost an enormous sum to placo it on streets where there were tramlines. Concrete beds required a topdressing of macadam. Again the streets wero networks of eervico pipes, which would have to be removed and placed on the footpaths. What would happen if the sewerago was blocked? If they took all this into consideration, they would see that the City Engineer's figures wero not far wrong. The concrete road scheme would cost £13,800 per mile, the interest and sinking fund on which, at 5 and 2 per cent, respectively, would amount to £934 ner mile per annum. In addition to that was maintenance and repairs. Could the | city stand such a charge? For that reason he wis going to support the committee's recommendation. Cr. Beanland (chairman of the Works Committee) said the committee had not the monev to make the experiment. He described the figures of Cr. Peek's contractor as nonsense. No good builder would do the work under £2 5s or £2 10s per yard. 7f concrete was to he put on the Christchurch streets, they wculd have to carry the principle adopted in Wellington, and put all piping under the footpaths. Where wu9 a better street to bo found than Tuam street ? It was equal to Queen street, Auckland. It had been three vears, and cost £55 per chain Cr JPeek said the work had not been done fourteen months. Cr. Boanland said he felt 6ure Tuam street had been done two years. Concrete. roods might be a huge success in Christchurch, but before they adopted them they must alter the whole of their road scheme; they would not be

able to do it out of revenue. If the Council derided-on the concrete experiment the City Surveyor had in mind a piece of road which he would like to use for the purpose. The amendment was declared carried oil tho voices.