Productivity improvement methods in earthmoving projects

Improving construction productivity is essential today due to stringent financial resources. Micro-computer based decision support systems and operational research models can be used as tools at different phases or construction projects to improve the productivity and to minimize the cost. -- Among the wide variety of operations on many construction projects, the earthmoving operation plays an important role. Selection of the most appropriate type, size, and number of machines, and the optimal distribution of the cut and the fill quantities of soil are therefore significant in reducing the overall cost of a construction project. -- In this thesis, a micro-computer based decision support system is developed for selecting the most economical group of machines for an earthmoving project. An operational research model based on the transportation algorithm is also introduced to find the optimal cut and fill distribution of an earthmoving operation. -- The developed micro-computer based decision support system consists of a computer program, which simulates a consultation between an expert in equipment selection and a. user. It presents a series of questions and a series of answers for which the user has to respond according to the requirements and the conditions of the earthmoving operation. For convenience, the system is developed in three phases. -- In the first phase of the system, the selection of the suitable types of equipment for the earthmoving operation is made from eleven different types of earthmoving machines. In the second phase of the system, after checking the height and weight constraints that may be applicable to the site and to the haul roads, the production rates of all the models and sizes of the usable machines are determined. By comparing the cost per unit volume of material handled by each group of machines, the most economical group is determined in the final phase, to suit the scheduled duration and the total quantity of material to be handled of the earthworks project. Also, the cost per unit volume of material to be handled, the expected production rates, and the durations of the employable groups of machines are presented to the user. -- Once the most economical group of machines is decided, using the introduced operational research model, the optimal distribution of cut and fill quantities of an earthworks operation can be deduced. -- The application of the proposed micro-computer based decision support system and the operational research model are simple and can be used as effective tools in improving the earthmoving productivity of construction projects