Analysis models and design guidelines for high-clearance scaffold systems
Abstract
The highest risk during a structure's lifetime is generally during the construction phase. This is evidenced by the fact that most structural failures occur during construction rather than after the structure is completed and is in service. The construction period can represent the most critical phase in a building's lifetime. The scaffold support system, a combination of steel scaffolds and wooden shores, is typically used for the temporary support of high clearance concrete buildings in Asia. These types of structures, generally having clearances of greater than 4 meters, include museums, hangars, churches, gymnasiums, etc. Scaffold support systems are often used because they are convenient, versatile, and relatively inexpensive temporary support structures. No guidelines exist, however, for the design and use of these temporary structures during construction. Modern design codes only concentrate on ensuring the safety of the structure during its service life. Furthermore, concrete placement patterns during construction may influence the loads on the temporary supports. Little is known about these effects, either. This thesis mainly focuses on the safety of the scaffold support system and the influences of the concrete placement pattern load on the temporary supports during construction. There are five major parts in this thesis. First, the outline, basic assumptions, and collapse predictions of the entire scaffold support system are introduced. Second, the analyses of the scaffold system proceeds in two steps: the steel scaffold system and scaffold support system (steel scaffold system with wooden shores). Third, a simplified model is introduced to simplify the 3-D problem into a one degree of freedom model. In addition, the set concept for the scaffold support system is also introduced. Fourth, the pattern load effects of concrete placement are investigated, and a simplified influence surface model is used to predict the maximum reaction force and its location. Finally, the safety of this scaffold support system is investigated, and design guidelines and work checklists are presented for use in actual construction practice.
Degree
Ph.D.
Advisors
Chen, Purdue University.
Subject Area
Civil engineering
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.