COMPASS

The COMPASS software consists of four modules: Mix Expert, Aggregate Gradation, Mix Proportioning, and Mix Optimization. Each module is designed to function as an independent tool. Used together in a progressive manner, the system of modules results in a comprehensive optimization tool.

The Mix Expert module consists of a knowledge-base used as a “first cut” in optimizing a mix. It identifies a performance criteria and subset of materials that should be considered to meet those criteria. Computer-based guidelines (software) employing numerous models will then reduce these materials further, identifying the “best” mix for the job.

Optimization begins with a desired set of criteria (targets). In order to meet these targets, the user must first define under what job-specific conditions the pavement will be constructed (the design, environment, and construction). They must also define what materials are available to them, and possibly what the cost of the materials will be. As a result of this information, an optimum mixture can be determined using a systems approach.

In the end, the software can be used in three modes. First, in a planning mode that allows decisions about the best mix to be made, well in advance of the placement. The second mode will probably be the most common, allowing the user to derive the project mix based on knowledge of the specific materials available to them. Finally, a third mode will allow the user to assess the impact of changes in their mix as they impact the behavior and performance of the concrete pavement.