|M.Sc Student||Khoury Simon|
|Subject||Development of an Automated Model for Road Construction|
Control in a Geographical Information System
|Department||Department of Civil and Environmental Engineering||Supervisors||Professor Ronie Navon|
|Professor Emeritus Yerach Doytsher|
|Full Thesis text - in Hebrew|
Manual control of road construction is expensive, time consuming and error prone. Hence it is done infrequently, or is based on rough estimates. Previous attempt to automate this process developed a model which had to assume that work progresses according to plans. This assumption permitted the use of predetermined work envelops (WE). The difficulty which appeared during the site experiments in this attempt was that the actual work did not progress according to the pattern of the predefined work sections (WS) of the plans. This difficulty was overcome by a manual definition of the work performed at the end of each working day as well as the corresponding WS.
The need for manual determination of the work done by every piece of equipment at the end of each day and the need for a more automated measurement method, motivated the current research. Clearly a new approach is needed whereby both the time spent performing work and the amount of work done during that time, will be defined automatically – this approach was named the Dynamic Work Envelop (DWE) approach, on which the algorithm of the control model, developed in the present study, was based. This algorithm determines the work envelope during its operation, according to measured locations and then determines, concurrently, both the amount of work performed (e.g. the compacted area) and the period within which it was done – the calculation of the inputs and the determination of completed activities based on these data is then trivial. The dynamic approach also alleviates the problems caused by the fact that the actual progress does not follow the planned one.
To implement the DWE method, an algorithm was developed, based on the notion that the amount of work performed by certain equipment is represented by the area that this equipment "covers" in its progress, assuming that the work in that area was performed completely. The study focused on developing the mathematical tools to calculate the work area of rollers used for compacting the asphalt layer.
A field test was conducted to examine the new approach. The results this test indicate a deviation, between the work areas received according to the model and those actually performed, ranging between c. 5% – 10%.
An economic analysis of the proposed system shows that it is more economical than the manual methods, especially if the control information is needed at a higher frequency than biweekly.