ITA POSITION PAPER ON TYPES OF CONTRACT

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 Tur nkey; and Build-Operate-Transfer. Advantages, disadvantages, and relat ed risks are summarized for each type of contract. Aspects of multiple construction contracts and contracting with an association of contrac tors are addressed. The three main methods of pricing-lump-sum, cost-r eimbursable, and unit-price-are discussed in detail. Other aspects of compensation, such as bonus payments, currency of price, adjustment an d revision of price, and payment conditions, are also addressed.