DEFECTS IN CONCRETE

Evening Post, Volume CXVI, Issue 65, 14 September 1933, Page 4

DEFECTS IN CONCRETE

THE GREAT NORTH ROAD

SURFACE HOLES AND CRACKS

Extensive defects have been found in the portion of the Great North" Road between the Whau Bridge and Titirangi Road, which was constructed in concrete by the Auckland City Council about eight 'years ago, according to a report presented by the New Lynn Borough foreman (Mr. B. McKenzie) at Monday's meeting of the Borough Council (reports the "New Zealand Herald"). The road was recently inspected by Mr. McKcnzio in company with Mr. A. M. Page, engineer for the Main Highways 'Board in the No. 2 licensing district.

Mr.. McKenzie said there were holes in some places 3in deep and 4in across. As many as seventy of these holes were found in a chain length, the worst section being near the Whau Bridge, which was! put down first. North of the bridge. the surface gradually improved, and be.yo'nd Titirangi Road was in comparatively good condition. For some weeks the Borough Council has been filling holes in the concrete with bitumen.

Many slabs were cracked, owing to water seepage, and' this could be obviated only by a system of drainage. As most of the shoulders consisted of .'impervious "clay and few, if any, outlets or drains were put in, the shoulders were kept in a state of dampness, and when the wheels of heavy ■ traffic sank into, the soft clay the ehoi lders were forced up. This action was. evident in practically the whole length of the road' way, so that, the shoulders .were higher than the adjoining concrete, thus forming a small gutter which on the flat formed pools of water, with the attendant scour finder traffic. . , . .

The remedial measures suggested, by the foreman Vievc the removal' of the shoulders,' the digging of a trench-to a depth of 6in below the bottom edge of the concrete slabs, and the laying'of. field tiles along the edge td. wherever an outlet was obtainable. It is proposed that the trench should then be hand-packed to road level and the shoulders re-formed to a distance of 2ft from the .edge and sealed with roadseal. The total estimated cost was £718. ' ■ "It s6ems to me the only thiug to do is to get the proposals carried out," said Mr. A. Drury. "The road was intended to' last fourteen years, and already it has been down over half that period," eaid tRe Mayor (Mr. G. Laweon). "I am surprised it has stood bo well." ■■• Mr. Drury: It should last longer than that. . .... v It was decided to submit the report and recommendations to the Main Highways Board. ■ ,