Member’s Doubt On Tunnel Plan Detail

Press, Volume XCIX, Issue 29299, 2 September 1960, Page 10

Member’s Doubt On Tunnel Plan Detail

Admitting that he had never been in a tunnel under construction, Mr W. P. Glue discussed details of the plans for the Christ-churcti-Lyttelton road tunnel, prepared by the Ministry of Works, alt yesterday’s meeting of the Road Tunnel Authority. “We have relied upon the best consultants in New Zeeland,” commented the chairman (Mr W. S. Mac Gibbon) who was authorised to accompany Mr Glue at a discussion to be arranged with the District Commissioner of Works (Mr E. C. Smart). “The plans and specifications, signed by the local bodies concerned. are now on the desk of the Minister of Works, and we expect to get them signed by him and back to Christchurch so we can proceed with the preliminary steps for the calling of tenders," reported Mr Mac Gibbon.

When Mr Glue produced plans and began to describe them, Mr Mac Gibbon asked: "Are these your personal observations?" “Yes.” replied Mr Glue. “I admit I am not a tunnel contractor." One clause in the specifications which interested him. said Mr Glue, was that Maori artifacts, minerals and gold recovered during construction remained the property of the authority. "That is the usual clause in tunnel contracts.” replied the chairman. Assuming a 30 feet excavation for the 28 feet tunnel 6500 feet in length, 235,000 cubic yards of rock would have to be removed, said Mr Glue. That was not a tremendous amount. The volume of concrete work was 38,500 cubic yards, which also was not tremendous. Extra Grouting Urged “I am not criticising the job.” said Mr Glue when he discussed the main beams and slabs. "Have you discussed it with anybody? With Mr Somers?” asked Mr Mac Gibbon. “No—only with Jack Holliss,” replied Mr Glue. Extra grouting to give protection from water affecting the steel tie rods was suggested by Mr Glue. The chairman: Have you seen this construction in any tunnel? Mr Glue: I have never seen construction inside any tunnel at all.

It would not cost much more to build the tunnel with the slabs slightly smaller and not so close together, said Mr Glue. The extra grouting would give more cover of the rock.

A rod which had been removed from reinforcing of the piers in an English Park building because of deterioration from water coming in was produced by Mr Glue. “Jack Holliss suggested that bronze rods should be used but I think more coverage should be given.” said Mr Glue. "The Public Works are not infallible. I think they are quite reasonable and if we make that slight suggestion it will show we are interested. As a member of the authority, I have every right to express an opinion. As to the rest. I think it is a very fine specifics tipn.” Mr Mac Gibbon: You suggest that this matter be referred to the consultants? Mr Glue: I do. “Over His Head”

Criticism of the plans was over his head, said Mr L. G. Amos. If Mr Glue wished to take his views any further, he should have a talk with the consultants. “But as far as I am concerned, it is beyond us.” said Mr Amos. “We are beyond the stage of discussing plans and specifications.” But if he had helpful suggestions, Mr Glue was to be commended. Mr Glue said he had discussed slab work with the city engineer and Mr George Chapman (city engineer’s department). Mr Chapman had said the grouting would not be passed for an ordinary job. "We must play safe over this.” said Mr Mac Gibbon when the authority agreed that the chairman should accompany Mr Glue in any discussion on the safety factor in the tunnel construction. Tender Acceptance

There was no reason, the Commissioner of Works (Mr F. H. M. Hanson) had advised him. why the authority should not know the name of the successful tenderer by December 16. said the chairman. Because of airmails, two months should be ample in which to tender.

"So we will turn the first sod on December 16 (Anniversary Day),” said Mr Mac Gibbon. The authority gave instructions for the purchase of five properties on the Lyttelton side of the tunnel. Negotiations for the purchase of land at the Heathcote end were reported to be proceeding. . „ .■ A garage company s application for first offer of a lease to operate a breakdown and service station at the Heathcote end was held over, as the authority has to decide whether it will itself operate the services.