Marine Deep Cement Mixing (Cutter Soil Mixing Technique)

Abstract

In recent years, marine deep cement mixing was widely adopted in Hong Kong as the ground treatment method for many mega reclamation projects. Compared to the traditional dredging method, the deep cement mixing method is renowned for its environmentally friendly and high-quality standard. The installation of the deep cement mixing works will generate less vibration to the surrounding and prevents bringing the toxic material into the open water. Also, the deep cement mixing can provide a stable foundation for the land formation and comparatively less settlement is expected. The Cutter Soil Mixing technique is a type of deep cement mixing method. It is developed based on the Hydrofraise Cutter technology, crushing the soil through two counter-rotary cutters, and simultaneously mixed with a slurry binder to achieve the contract required strength. This paper presents a recent ground improvement project in Hong Kong with the application of marine Cutter Soil Mixing technique. Several essential working parameters such as mixing factor, dosage design and the criterion to achieve the top of competent stratum for the Cutter Soil Mixing installation are discussed. In addition, real time supervision and monitoring system by using a set of sophisticated instruments are introduced. The environmental considerations and measures of the project are also presented in this paper.