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Experience and business intuition of a contractor are often insufficient to ensure that tender procedures will provide a good trade-off between the cost of bid preparation and the benefit of a high probability of winning a money-making contract. The authors put forward a set of decision-support models: a multi-criteria analysis for assessing the desirability of a potential new contract, and two linear programming models: one for calculating the total price, and the other for distributing the bid amount among the items of the bill of quantities to maximize the contractor's cash flows. Application of the models is illustrated with a numerical example. [ABSTRACT FROM AUTHOR]

Material supply-related decisions strongly affect economic performance of construction projects. To facilitate planning, the authors put forward a mixed integer linear programming model for optimizing supplies of materials or components that are consumed irregularly. The model's objective function is minimizing the total inventory management cost. As material prices change over time and cannot be predicted with certainty, they are expressed as fuzzy values with triangular membership functions. The planning horizon is divided into units of time to allow for seasonal changes and scope variations that affect consumption of materials. The model enables the user to determine economic order quantities for consecutive periods of construction works and to select most economical supply channels of a particular material/component. The model allows for material/component substitution. Substitutes may differ in level of prefabrication and thus in costs of on-site processing. To solve the problem the fuzzy model is converted into a three-objective linear program with crisp coefficients. An example illustrates benefits of using the proposed approach in reducing the total inventory cost. [ABSTRACT FROM AUTHOR]