| Abstract: | This paper describes the following contracting concepts applicable to tunnelling and other underground construction work: Design-Bid-Build; Partial Design-Construct or Partial Design-Build; Design-Build and Turnkey; and Build-Operate-Transfer. Advantages, disadvantages, and related risks are summarized for each type of contract. Aspects of multiple construction contracts and contracting with an association of contractors are addressed. The three main methods of pricing—lump-sum, cost-reimbursable, and unit-price—are discussed in detail. Other aspects of compensation, such as bonus payments, currency of price, adjustment and revision of price, and payment conditions, are also addressed. |
