The Civil Engineering and Development Department (CEDD) of the Hong Kong SAR Government operates a certification system to regulate the use of permanent prestressed ground anchors in Government projects. According to the Environment, Transport and Works Bureau Technical Circular (Works) (ETWB TC(W)) No. 16/2004 "The Use of Permanent Prestressed Ground Anchors in Government Projects", all permanent prestressed ground anchor systems require the prior approval of the Director of Civil Engineering and Development (DCED) under the Anchor Certification System before they can be used in Government projects.
The Anchor Certification System ensures consistent and satisfactory standards in the provision of prestressed ground anchors, facilitates their specification, and saves time for designers, contractors, manufacturers, suppliers and the Government by eliminating repetitive checking of project proposals. An Anchor Certificate, signed by the DCED, will be issued to cover prestressed ground anchor systems and ground anchor types found acceptable for use in Hong Kong. The Anchor Certificate specifies the conditions and limitations for use of the Certified Ground Anchors in Hong Kong. The Anchor Certificate also names the anchor contractor (i.e. the Nominated Anchor Contractor) authorized by the anchor supplier and accepted under the terms of the Anchor Certificate to install the Certified Ground Anchors.
Notwithstanding certification, a retaining structure or slope installed with Certified Ground Anchors will still need to be adequately designed by the designers, and checked by the Geotechnical Engineering Office (GEO) in accordance with ETWB TC(W) No. 29/2002.
Application for Certification
Application for Anchor Certificate requires the applicant to submit details in accordance with the requirements stipulated in Appendix B in Geospec 1 - Model Specification for Prestressed Ground Anchors. The applicant should demonstrate that the anchor components and the corrosion protection of the anchor system comply with the requirements stipulated in Geospec 1. The applicant should also demonstrate that they meet the technical and management criteria for certification as stipulated in the following paragraphs. In addition, the applicant should submit details about the experience and qualification of the personnel employed by the Nominated Anchor Contractor to demonstrate that they are adequately experienced in installing the anchor system. The application for Anchor Certificate should be submitted to the Head of GEO for assessment.
Minimum Technical and Management Criteria for Certification
- Job Experience
Should produce evidence of authorization from the Principal for the Anchor System for the contractor to act as Agent in Hong Kong, and should have installed the anchors on at least one major project.
- Top Management
At least one personnel with 5 years of relevant experience in ground anchor, and shall have the necessary managerial skill to ensure good quality of certified ground anchor systems are installed. Top management shall include the President, Chairman, Director, Managing Director, Executive Director and General Manager of the Company.
- Technical Staff
At least one Engineer and Site Engineer with 5 years and 2 years relevant experience in ground anchor respectively, and a general foreman with 3 years relevant site experience in ground anchor.
- Plant and Equipment
Should possess plant and equipment to install the certified ground anchors in accordance with the Anchor Certificate.
- Office/Workshop Facilities
All applicants must posses or set up in Hong Kong a place of business. Storage facilities for continuous storage of a level of stock sufficient to supply replacement head components for at least ten anchors and for ten additional anchors.
Guidance on Design and Construction of Prestressed Ground Anchors
Geospec 1 - Model Specification for Prestressed Ground Anchors recommends a standard of good practice for the design and construction supervision of permanent prestressed ground anchors. It provides a model specification, which stipulates the general requirements on the quality of materials, standard of workmanship, testing methods and acceptance criteria for prestressed ground anchors. It can be used as a reference for the preparation of Particular Specification.