Updating Linear Schedules with Lowest Cost: a Linear Programming Model

World Multidisciplinary Civil Engineering-Architecture-Urban Planning Symposium - WMCAUS

土木建筑工程

Biruk, Slawomir^1 ; Jakowski, Piotr^1 ; Czarnigowska, Agata^1

Lublin University of Technology, Faculty of Civil Engineering and Architecture, Department of Construction Methods and Management, ul. Nadbystrzycka 40, Lublin

20-618, Poland^1

关键词: Civil engineering projects;    Construction process;    Construction projects;    Graphical representations;    Linear programming models;    Optimization algorithms;    Project performance;    Scheduling problem;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/245/7/072011/pdf
DOI  :  10.1088/1757-899X/245/7/072011

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

Many civil engineering projects involve sets of tasks repeated in a predefined sequence in a number of work areas along a particular route. A useful graphical representation of schedules of such projects is time-distance diagrams that clearly show what process is conducted at a particular point of time and in particular location. With repetitive tasks, the quality of project performance is conditioned by the ability of the planner to optimize workflow by synchronizing the works and resources, which usually means that resources are planned to be continuously utilized. However, construction processes are prone to risks, and a fully synchronized schedule may expire if a disturbance (bad weather, machine failure etc.) affects even one task. In such cases, works need to be rescheduled, and another optimal schedule should be built for the changed circumstances. This typically means that, to meet the fixed completion date, durations of operations have to be reduced. A number of measures are possible to achieve such reduction: working overtime, employing more resources or relocating resources from less to more critical tasks, but they all come at a considerable cost and affect the whole project. The paper investigates the problem of selecting the measures that reduce durations of tasks of a linear project so that the cost of these measures is kept to the minimum and proposes an algorithm that could be applied to find optimal solutions as the need to reschedule arises. Considering that civil engineering projects, such as road building, usually involve less process types than construction projects, the complexity of scheduling problems is lower, and precise optimization algorithms can be applied. Therefore, the authors put forward a linear programming model of the problem and illustrate its principle of operation with an example.