Factors for generating initial construction schedules

Schedule generation is a vital construction planning tool which is founded on experiential knowledge and on engineering and management procedures. In this dissertation a Knowledge-based Systems (KBS) approach is followed for acquiring, formalizing and representing construction scheduling knowledge. The knowledge acquisition process is based principally on the interviewing of experienced construction schedulers from five different construction firms. This process results in the formalization of key factors utilized by experienced schedulers for developing initial construction schedules. A primary focus of this dissertation is the identification of the factors used to determine a logical sequencing of construction activities. Four major factors that govern activity sequencing are formalized in this dissertation: (1) physical relationships among building components, like supported-by, embedded-in, etc. ; (2) interaction among crews, equipment, materials, etc. ; (3) requirement of an interference-free path for components and their installation; and (4) code regulations to insure the safety of construction operations and the ability to supervise and inspect installed components. This dissertation also includes the development of a KBS prototype named CASCH, Computer-assisted $\underline{\rm Sch\/}$eduling, that incorporates a subset of the acquired knowledge. The function of the prototype is to serve as an aid to formalize and represent the acquired knowledge, and to demonstrate the feasibility of delivering scheduling knowledge in a way that enables user interaction. CASCH takes advantage of the object-oriented and rule-based knowledge representation tools offered by KEE$\rm\sp{\sc TM}$, the Knowledge Engineering Environment distributed by Intellicorp. The prototype does not address the knowledge of precise detail about components, nor detailed task ordering. It focuses on the typical sequencing rules to aid in the generation of macro-level schedules. This research work focuses on the scheduling of typical mid-rise commercial building construction. Typical mid-rise commercial building construction is defined here as the construction of building features that are common to most residential and office buildings.