Abstract:

The connection gallery with freezing method is a selfrisk project, and there is not any risk management measures for early stage of connection gallery with freezing method. Hence, the risk source identification and risk level evaluation of the connection gallery with freezing method are analyzed. The technical measures that can reduce or avoid the risk of the connection passage with freezing method are proposed, which include: (1) The location of the connection gallery should be rationally selected by avoiding areas with serious environmental and geological risks. (2) The number of steel pipe pieces at the connection gallery should be appropriately increased to enhance the overall strength of the tunnel structure and the ability to resist risks. (3) The secondary grouting should be carried out behind segments ahead of and behind connection gallery, and the ground should be reinforced. (4) The structural dimensions of the connection galley and pump station should be optimized to facilitate freezing construction. (5) The special design of freezing method reinforcement should be rationally carried out to avoid freezing weak surface.

Key words: freezing method, connection gallery, risk management, early stage, risk evaluation