THE first phase of the redevelopment of Murrayfield stadium is

complete, and 26,000 rugby enthusiasts will take their seats in the new

north and south stands for the Scotland v Ireland match on Saturday.

The completion of the #13.8m north and south stands within the 42-week

contract period is a major achievement for the engineers, architects,

and contractors. About 54,500 will attend Saturday's game, and when the

entire #36m project is completed late next year Murrayfield will seat

65,000 spectators.

The schoolboys' benches have been incorporated in the east stand,

which is otherwise largely unchanged, except that its roof rises at each

end to meet the vast new 43-metre cantilever roof of the new north and

south stands.

When the redevelopment is completed the most expensive seats will be

in the west stand, which is being demolished and rebuilt in March. The

48-metre cantilever roof on the west stand will be one of the longest in

the world, the lack of supporting columns providing spectators with

unobstructed views of the field.

The overall shape of the grandstand is dictated by the seats and is

similar to the American Superbowl. ''Murrayfield is conceptually the

same but on a smaller scale, and it has better facilities than the

Superbowl because it is new and equipped to higher specifications,''

said project engineer Jim Travers of Thorburns.

''When the second phase is complete the Scottish Rugby Union will have

one of the best stadiums in the world.''

Thorburn engineers have been responsible for several outstanding

football stadia, most recently at Ibrox, in the early 1980s at

Nottingham Forest and Millwall, and also for the rugby stadium at

Windsor Park.

The design and construction challenges at Murrayfield are unique.

''The major problem was designing a structure which could be built in a

very short space of time,'' said Jim Travers.

''The biggest challenge was that the scheme had to be built within the

42-week contract period -- a very tight schedule and a tall order for

the design team.''

Huge rear columns support the structure. Each weighs 40 tons and is a

fundamental part of the frame. At every column the roof becomes higher,

posing a difficult geometrical problem which was computer modelled.

The dynamic performance of the completed structure -- its ability to

deal with snow load and the effect of strong winds on the cantilever

roof -- was also assessed using computer models and the real design work

began in the summer of 1990.

The stadium seats are predominantly blue and white, with the upper

decks woven to create the SRU tartan in green, white, blue, black, and

magenta, and providing grandstand views of the playing field and across

to the Pentland Hills.

Clear domes of transparent polycarbonate have been incorporated in the

cantilever roofs to allow sunlight to filter on to the playing surface,

which the SRU head groundsman Bill Elwood has in top-class condition

ready for Saturday's game.

The redevelopment of Murrayfield has been a team effort among

Thorburns, the Miller Partnership architects, and mechanical and

electrical consultants Kirkpatrick and Partners, responsible for

services within the stadium. The main contractor is Costain

Construction.