الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
A model for circular base plates based on the finite element method was developed. The principal haracteristics affecting the behavior of the base plate system were incorporated in the model. Steel was ideal¬ized as an elastic-perfectly plastic material. Concrete was assumed to be an isotropic homogeneous material when loaded in the elastic range and was assumed to be an elastic-perfectly plastic material in the compression zone. Cracking and crushing of concrete were considered also in the non¬linear range of loading. Steel base plates were connected to concrete footings through bond-link elements in such a way that a slip and separa- tion between the two ma~erials was permitted. Linear rectangular elements were used in this study to represent the steel base plate and the concrete footing. An integration technique was used in this study for elements in
which the bending behavior was important
Several numerical examples were solved to demonstrate the validity
of the proposed model. The analytical solutions compared favorably with experimental results. The proposed model appears to be adequate for pre¬dicting the ultimate load for ircular base plate systems. A limited
number of solutions was obtained to study the effects of certain variables
influencing the ultimate load carrying capacity of the base plate system.
The proposed analytical model is capable of analyzing and predicting
the ultimate load carrying capacity for circular base plate systems. The
effects of the material nonlinearities, cracking, crushing, and yielding
were included in the analysis and the material model was adequate to ana-
lyze the base plate Syst9ms.
The compressive strength of concrete, yield strength of steel, rela¬tive area of base plate, and thickn~ss of plates are the major variables influencing the behavior of the base plate system. Experimental results
in this study indicated that circular base plate systems exhibited a lower bearing strength than square base plates which were loaded through wide flange sections (14).
The base plate model can be extended to include reinforcement in the concrete footing to better simulate actual design conditions. Also, dif¬ferent boundary conditions can be included in the model to allow for interaction between the structure and the surrounding soil. The results
obtained suggested that more general problems, such as a three-dimensional
base plate system which includes plates loaded by wide flange columns, can be solved by the method used in this study.