Concrete Mix Designer is a prototype expert system that provides the proportion of the trial mix of concrete in accordance with the ACI method. It was developed using the Personal Consultant Plus expert system development package. As most expert systems, this system can justify its conclusions, can be incrementally expanded, and has an easy-to-understand knowledge base. It also has a tutorial for fundamental questions of the proportioning of concrete. The system is very useful for civil engineering students as well as practicing engineers.

Presents an optimum design for a given prestressed concrete member, chosen from an existing shape library and a given external load system. It is emphasized that, as part of the given data, the tendon diagram is determinant in designing a prestressed concrete member. The analysis is based on the elastic behavior of the member, and a realistic investigation of the capacity of the member is performed. The whole process implies an appreciable volume of computations and is suitable for digital computers. A design aid for the initial and final stages of the prestressed concrete member is also presented.

SP111 The area of computer applications in concrete technology is growing rapidly. Where it was once the exclusive domain of researchers and scientists, it is now an area where fabricators, detailers, designers, students and educators are making significant contributions. The different applications presented in this important ACI publication will be of interest of individuals dedicated to the correct use of concrete as a construction material. "State-of-the-Art Computer Applications in Concrete Technology" offers the latest information on topics such as microcomputer-aided design of reinforced and prestressed concrete elements; computer analysis of R/C columns in biaxial bending; spreadsheet template of concrete box design; concrete mix design; and personal computer-aided design of post-tensioned slabs on expanding and compressible soils. This ACI publication is designed to keep you abreast of the latest happenings in concrete technology and is intended to enhance the technological tools available for the correct, safe, and economic use of concrete.

With the rapid advancement of powerful and relatively low-cost minicomputers, refined analytical techniques are now possible to apply during the design stage. An interactive program is presented herein for such refined analysis of beam-column sections under generalized biaxial bending and axial load. The program has a wide range of analysis options for the estimation of complex hysteretic response and three-dimensional interaction diagrams. In addition, it is equipped with a portable window manager, mouse driven input, and editing options and color graphics for on-line inspection of input and analysis results. Different types of materials can be specified such that reinforced, prestressed concrete or plain/composite steel sections can be considered. The section model is idealized as an assembly of fibers acting under a uniaxial state of stress. The section model theory is extended to represent entire members for the nonlinear finite element analysis of complete buildings.

COLUMN is a computer program written to select cross sections for reinforced concrete columns by simulating the reasoning processes used by structural engineers. The logic used to select, evaluate, and, if required, modify a section is described. Provision is made for the designer to impose, a priori, any restriction on the concrete dimensions or reinforcement that may be desired. The program proportions and details tie dand spiral columns, braced or unbraced for either uniaxial or biaxial loading. Slenderness effects are considered using the moment magnifier method. The design of a tied column with examples of different user-imposed restrictions is included.