Following is a question by Dr the Hon Tang Siu-tong and a reply by the Secretary for Housing, Mr Dominic Wong, in the Legislative Council meeting today (February 7):
In his reply to my question on November 29 last year, the Secretary for Housing pointed out that the selection of contractors for remedial works to the foundations of Blocks K and L of Tin Chung Court in Tin Shui Wai had already reached the final stage, and such works would commence in January this year. The Secretary also mentioned that the consultant commissioned by the Housing Department ("HD") had found a new machine that could facilitate piling works and included it in the new remedial scheme as well. In this connection, will the Government inform this Council of:
(a) the name of the contractor awarded the contract for the remedial works and the current progress of such works;
(b) the functional features of the new machine, the country from which it is imported, the structure and height of the buildings to which it may apply, as well as the geological condition of the sites on which it can operate; and
(c) the details of the new remedial scheme, and whether these have been endorsed by the independent third party, engineering consultant Binnie Black; if so, whether the consultant concerned will be held responsible under the contract signed with the HD if the scheme is proven to be unworkable or defective in the future?
On January 18 this year, the Building Committee of the Housing Authority decided to award a contract for the remedial works to Gammon Construction Co. Ltd. The actual works are expected to commence later this month, and C M Wong Associates Ltd., the remedial scheme design consultant, will supervise the implementation.
The new machine which I referred to in my reply to the Honourable Member's question on November 29,2000 is called "hydraulic piling jacking machine". It installs, by hydraulic jacking, new steel H-piles next to existing piles to strengthen the foundation. This piling method, developed in China, can be applied in the geological conditions of Tin Shui Wai area and is suitable for supporting multi-storey buildings. The advantages include low piling noise and minimal disturbance to ground soil and underground water.¡@Moreover, in the course of jacking down the steel pile, the ground soil will be compressed to enhance its load bearing capacity. In June 2000, a trial test of the "hydraulic piling jacking machine" was carried out by the Housing Authority in Tin Shui Wai, which test has confirmed that steel H-piles can be jacked into deep soil strata to support a building with a height of more than forty storeys.
As regards part (c) of the question, the remedial scheme for Blocks K and L of Tin Chung Court, using the "hydraulic piling jacking machine", has been carefully examined and endorsed by Binnie Black & Veatch HK Ltd., which is an internationally renowned geotechnical and structural consultant. In addition, in December 2000, the Housing Authority also appointed an independent foundation expert, Professor H G Poulos, to review the effectiveness of the remedial scheme. He has concurred that the proposed remedial scheme will be effective in restoring and strengthening the foundation of the two blocks to their original specifications. Binnie Black & Veatch HK Ltd. will be responsible for auditing the implementation of the remedial scheme. If the remedial scheme it has endorsed is found to be unworkable or defective in future, the Housing Department will take action against the Company and any other parties involved in the remedial scheme in accordance with contractual provisions.
End/Wednesday, February 7, 2001