The Hong Kong Council for Testing
and Certification (HKCTC) and Hong Kong Accreditation Service (HKAS) co-organized
a seminar named “Latest Development in Construction Material Testing,
Inspection and Certification” held on 26th Jan 2018. In recent years, infrastructure and construction projects in Hong Kong
are being carried out in full swing.
Product certificate schemes for a wide range of construction materials
have been developed to help safeguard the quality of construction materials. In the beginning, all guest speakers and
organizers took a group photo.
(Left: Ir. Dr. Jeffrey Lam, Ir.
Dr. Wallace Lai, Prof. Albert Yu (Chairman, HKCTC), Ir. Prof. Joseph Mak, Ir.
Prof. Philip Chung and Ms. Jane Lee (Secretary-General (Test &
Certification), HKCTC))
The first speaker was Ir. Prof.
Philip Chung (Deputy Head of Geotechnical Engineering Office (Planning and
Standards); Hon. Professor, Department of Earth Sciences, HKU) and his
presentation entitled “Testing of Cores taken from Cement Stabilised Soil”.
Firstly, he introduced what was
deep mixing that was a technique of mixing chemical binder (cement/lime) with
soil to improve the engineering properties of the soil. (In diagram – Improved ground area). There are three mechanism of Deep Cement Mixing
(DCM) to improve consistency and increase strength below.
-
Ion exchange at the surface of clay minerals
-
Bonding of soil particles
-
Filling of void spaces by chemical reaction products.
(Example by HK Airport Authority –
Deep Cement Mixing for
the three-runway system)


