A framework for optimized and automated tower crane planning in preconstruction phase

The construction industry has only been using tower cranes to assist lift tasks for less than eight decades. In this time, various types of tower cranes have been developed to suit specific requirements of different construction job sites. However, tower cranes are less broadly used in North America, especially in the United States, than Europe and Asia. This is partially attributed to ineffective tower crane planning in the preconstruction phase, which lacks a formalized planning process and a commonly agreed upon planning target. In the state-of-practice, Engineers conduct iterative planning in a manual approach using mostly 2D representations of project data and equipment specifications. The chance of identifying an optimal solution is small and site-specific constraints, such as spatial-temporal conflicts and the ever-changing clearance when collaborating with other machinery equipment are subject to being overlooked. A formalized planning process, along with advanced modeling, simulation, and optimization techniques, provides intuitive observation of the multiple dimensional solution space of the tower crane planning problem. It has the potential to automate and advance the planning of machinery equipment used on building construction projects. This dissertation research enhances tower crane planning in the preconstruction phase using parametric modeling, visualization, four-dimensional simulation, rule-based checking, and optimization algorithms. The overall goal of this study is to create a framework that allows engineers and researchers to formalize site-specific constraints of tower crane plans, and to automate the analysis, evaluation, and visualization of multiple alternative plans. In order to identify the optimal solution, an optimization formulation using mixed-integer programming was introduced. An application of such framework is presented in real-world scenarios and the results demonstrate that the effectiveness and efficiency of tower crane planning in the preconstruction phase can be improved and a broad range of alternative plans can be quantitatively assessed for communication, training, or continuous improvement. The main contribution of this study includes the introduction of a machinery equipment plan assessment framework. This framework incorporates project data (e.g., schedule, site-layout, lift demands) and a specialized tower crane planning model to visualize, identify, and analyze the obstructions in alternative plans with respect to spatial, capacity, and safety constraints.