TAC Corporation, in pursuit of happiness of all employees, and pursuing zero subsidence in all Shield construction projects.

TAC Corporation

Additive Injection

We stock a wide range of additives which cover every variation of soil quality possible. With our products we aim to support the stability of the tunnel face and the smooth discharge of slurry from all projects.

What is Additive Injection?

Earth pressure balanced shield machines works by injecting additives into the tunnel face. The shield machine then mixes the additive with the soil mechanically improving the soil condition. The space between the face and the bulkhead of the shield is filled with this improved soil, to which pressure is then applied using the driving force of the shield. TAC Corporation specifically deals with the injection materials and injection systems of complex additives rich in mineral, polymers, foaming agents and the like. Our soil handling system can cope with all kinds of soil types.

Principles of Additive Injection.

The state of the excavated earth and sand is shown in the diagram as shown below. Moderate additive injection enables plastic excavation of earth and sand by plastic fluidization.


TAC Corporation