Jet grouting to start

getimage555Thousands of tonnes of concrete are being injected into the Christchurch Town Hall’s foundations as part of a multi million dollar project to strengthen the building.

This week contractors began the lengthy process of jet grouting the quakedamaged building’s foundations. They are using three grout machines that have been imported from Germany for the work, during which more than 1000 large concrete piles will be injected eight metres into the ground.

In the February 2011 earthquake the land beneath and around the Town Hall was severely damaged. Although the building itself fared relatively well, significant strengthening of its foundations is needed. Jet grouting has been identified as the most effective repair solution to address the land issues underneath the building.

‘‘Grout and water is injected into the ground at high velocity to create columns of soilcrete, which is soil cemented with grout. The columns will overlap and interlock to create an earthquake resistant underground wall of columns that will protect the building from soil movements,’’ said Project Manager Paul Youngman.

A total of 27,000 cubic metres of jet-grout concrete – which would fill 270 average family swimming pools, 37,500 bath tubs or 200 buses – will be used during the process.

A thick concrete slab will be laid over the concrete columns once the jet-grout work is complete, which will help to bring the Town Hall up to 100 per cent of New Building Standard.

Contractors have spent five months preparing the site for the jet-grouting work, which is expected to be completed in June next year. It is the first stage in the $127.5 million repair of the Town Hall.

Christchurch City Council anchor projects unit manager Liam Nolan said the restoration work would ensure the Town Hall could continue to be enjoyed by Christchurch residents for the next 50 years and beyond.

‘‘The Town Hall is one of the city’s most treasured civic and heritage buildings and this restoration work will ensure it is better and stronger than it was pre-earthquake. Starting on the Town Hall foundations marks the culmination of four years of work. This has included engineering assessments, going through a tender process and appointing a contractor to undertake the restoration work,’’ Nolan said.

‘‘By the time we’ve finished work on foundations, the ground underneath the building will be significantly stabilised, ensuring we can get on with the rest of the work needed to restore this building to a world-class facility that can be used for many years to come.’’ .

The restoration of the Town Hall, which also includes a significant upgrade and refurbishment of the facility, is due to be completed in 2018.


  • Lois Cairns
  • The Press

Town Hall contract signed

1436384954063The Christchurch Town Hall has been largely stripped back to its concrete frame, but the bones of the place still evoke strong memories.

Those special memories were shared yesterday as the contract was signed to restore the earthquake-damaged building over the next three years: designs sketched on a kitchen table, children graduating and people queuing to visit on opening day.

The Christchurch Town Hall will be restored and strengthened over the next three years at a cost of $127.5 million. The main auditorium has been partially stripped out in preparation for the revamp.

The contract was signed in the heritage building’s foyer with restoration and strengthening work costing $127.5 million, largely funded by $68.9 million in insurance money.

Christchurch mayor Lianne Dalziel remembered visiting the building on opening day in 1972.

“I remember thinking this [foyer space] was so big,” she said.

“The queue went for miles. We all came in and we marveled at this incredible building.

“This place has been where we come together as a city to celebrate. This adds up financially and emotionally for the benefit of the city as a whole. Roll on 2018 and the opening day.”

Original architect Sir Miles Warren remembered designing the building on his kitchen table in Church Bay over the Christmas holidays in 1965.

“That was the beginning of a wonderful building process,” he said.

“It really was the most important commission that Warren and Mahoney ever received in competition. We became a national practice rather than just Christchurch architects in the process.”

Council rebuild manager David Adamson thought of family moments.

“All my children graduated through this place,” he said.

Regional Manager Steve Taw had memories of soft rock.

“I remember the last time I came here was for a concert. It was George Thorogood and the Destroyers.”

Council chief executive Karleen Edwards said the restoration would improve the Town Hall.

“We all have memories of coming here. We all have a special memory about this place. The city has missed having the Town Hall.

“There is a real opportunity to make this place better than it was.”

The building has been largely stripped back in preparation for the restoration. Carpets have been taken up, the floor of the auditorium has been stripped out and fixtures have been removed and stored. The process has revealed the full extent of how much the floor of the main auditorium warped in the Canterbury earthquakes.

The concrete floor of the auditorium bulges like the top of a sphere. The difference in height between the centre of the bulge and the edge of the floor is about 50 centimeters. Despite this, the walls and structure of the building have remained relatively intact.

The ground beneath the Town Hall will be fixed with more than 1000 jet grout piles, creating an eight-metre deep concrete grid beneath the building. A new concrete slab for the whole Town Hall complex will be poured on top of the new piles.

The Limes Room, which has moved towards the Avon River and risen at one end, will be suspended on scaffolding while new columns are built underneath to make it level again.


  • Stacy Squires
  • The Press

Town Hall survival looks likely

Christchurch’s earthquake damaged Town Hall is likely to be saved after a unanimous vote by a key city council committee.

All eight of Christchurch City Council’s community recreation and culture committee yesterday rejected the option of retaining only the main auditorium, and instead said they wanted the entire complex retained and repaired. The committee’s decision is expected to be endorsed by the full council on November 22 and should clear up uncertainty over where Christchurch’s planned new performing arts and music hub will be located.

The Christchurch Central Development Unit, in its blueprint for the central city, identified an area north of the Isaac Theatre Royal on Gloucester St as a possible location for two new performing arts auditoria but that was because it was assuming, for planning purposes, that the Town Hall would be lost.

CCDU director Warwick Isaacs said at the time of the plan’s launch the location was not set in concrete and would depend on what the council decided to do with the Town Hall. If it was retained, it would become the focal point for a hub, he said.

The cost of saving the Town Hall has been estimated at $127.5 million over four years. How much of that the council will have to stump up is unclear as it is still negotiating with its insurers. It is banking on getting nearly $69 million but staff conceded there was no certainty.

Committee chairman Yani Johanson said it was clear after reading assessments by heritage consultants on the option of saving only the auditorium that it was not the path to go down.

‘‘We need to work on saving the entire building,’’ Johanson told the committee.

‘‘The Town Hall is a cultural icon that is both internationally and nationally recognised for its design and acoustics. Given that we have lost so much built heritage already, I believe it is essential we do all we can to keep the Town Hall. It is a special place that tells a special story of our city’s past and should be safeguarded for the future.’’

At yesterday’s meeting, Sir Miles Warren and Jessica Halliday, from the Keep Our Town Hall group, asked councillors to save the entire complex, saying they were dismayed by the staff’s recommendation that only the auditorium be saved.

‘‘One cannot remove a third of the building without losing its aesthetic integrity,’’ Warren, one of the original architects of the Town Hall, told councillors.

Halliday said the Town Hall was a very important civic building and many citizens had precious memories associated with it.

‘‘A decision to demolish any part of this building without full exploration of all the options would be irresponsible,’’ she said.

Margaret Austin, of Voice of Music, which represents the music community, said they were strongly of the view that both the main auditorium and the James Hay Theatre should be retained and repaired if possible.

If the James Hay Theatre could not be saved, then a second performance venue with capacity for about 1000 people would be needed.

Graeme Wallis, also of the Voice of Music, said he still remembered the advertising jingle used in the late 1960’s to encourage people to donate funds towards construction of the Town Hall.


  • The Press
  • Lois Cairns
  • Photo: Geoff Sloan, The Star

What to do with council building

All but the main auditorium of the Christchurch Town Hall will be demolished if city councillors approve a controversial multimillion-dollar plan next week.

After getting detailed engineering advice, council staff have concluded that only the auditorium is worth saving and are recommending the remainder of the complex be demolished and a new entrance and gathering space built in their place.

They estimate the cost of repairing the earthquake damaged auditorium and building the new facilities at between $70 million and $80m.

But Cr Yani Johanson, who heads the community, recreation and culture committee, believes the town hall in its entirety can be saved and is recommending the committee push for it to be repaired to 100 per cent of the new building standard.

Council staff estimate that would cost $120.2m. The council has budgeted $127.5m over the next four years for work on the complex.

Johanson said yesterday that 314 of the 494 public submissions the council had received on the town hall during its annual plan process had supported fully repairing it, so knocking down parts should be done only as a last resort. A recent Press survey of 359 people showed 87 per cent said rebuilding was a priority.

‘‘Given the significance of this building, in my opinion we should be doing everything we can to save it,’’ Johanson said.

Heritage assessments obtained by the council had stressed the importance of retaining all of the building. Heritage consultant Jenny May, asked by the council to comment on retaining only the auditorium, said the town hall was Christchurch’s most important secular landmark and partial demolition would significantly diminish its ‘‘sense of place’’.

Ian Bowman, of Heritage Management Services, which was asked to peer-review May’s report, said in ‘‘the extreme case as a last resort, and where there were severely limited funds, could the retention only of the auditorium be considered. Removal of all but the main auditorium will lose a substantial section of the building. It would no longer occupy its corner site, and the view and appreciation of the building from Victoria St would be altered considerably. Removal of all these elements would significantly diminish its landmark status.’’

Architectural firm Warren and Mahoney, which was engaged by the council to produce an indicative design of how the town hall could function with the main auditorium alone, said it could still have a ‘‘strong architectural and urban presence’’. Keep Our Town Hall group member Ian Lochhead said yesterday it would be ‘‘greatly to the detriment of its architectural integrity’’ if the James Hay Theatre was demolished. The complex’s functionality would also be comprised as many large events staged in the town hall, such as university graduations, required both the auditorium and the James Hay.

‘‘The loss of the James Hay Theatre would be a really serious loss, both in terms of the total concept of the building and the way in which it is used,’’ he said.

Sir Miles Warren, who along with Maurice Mahoney designed the town hall, declined to comment, saying he wanted to share his views with councillors directly.


  • The Press
  • Lois Cairns

Council will try to save it’s own!

The city council will have ‘‘a damn good go’’ at ensuring the Christchurch Town Hall is saved, Mayor Bob Parker says.

City councillors will next week receive a report on whether any part of the town hall can be saved and how much securing its future is likely to cost.

Christchurch’s art community is worried the council may decide that repairing the building is too costly, but Parker has indicated there is strong support around the council table for its retention.

‘‘We will have damn good go at ensuring the town hall stays in place,’’ Parker said this week.

Support for saving the building is coming from around the world.

Barry Bergdoll, the chief curator of architecture and design at the Museum of Modern Art in New York, has written to the council pleading for it to keep the town hall .

‘‘It is always easiest to realise earthquake standards by demolishing and starting anew, but with it goes not only a very significant piece of history in a case such as this but a great part of local identity,’’ he said.

‘‘I firmly believe the Christchurch Town Hall is of such architectural and cultural significance that every effort should be made to ensure its survival.

‘‘It is perhaps one of only a few works of architecture in New Zealand that have had an influence on other buildings around the world, its acoustics much appreciated by famous international musicians.

‘‘It is a vital part of the city’s civic life moreover, and its loss would be a loss both psychologically locally and for architectural heritage worldwide.’’

University of Melbourne deputy dean and professor of architecture Paul Walker, in a letter of support, said the Christchurch Town Hall was internationally one of the most significant concert halls built in the past half-century.

‘‘When so many other venues for the city’s public life have been lost, it would be a great shame for the town hall to go, especially as it appears likely that it can be readily repaired,’’ he said.

While the rebuilding of the city would give great opportunities for new design, it was important to honour and retain places that have been important to the city’s sense of identity.

‘‘The repair and reinstatement of the town hall would be a wonderful boost to the city’s ongoing sense of recovery and confidence,’’ he said.


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