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The Drexel Masonry Design Competition (MDC) was instituted in the late 1980s by Drs. Harry Harris and Ahmad Hamid, and was held until 2001. This competition was facilitated by the donation of a small-scale block-making machine from the National Concrete Masonry Association (NCMA), and involved the design, construction, analysis, and testing of small-scale concrete masonry walls. Entries were judged based on ultimate strength, strength-to-weight ratio (structural efficiency), aesthetics, and accuracy of predicted load-carrying capacity. Through its tenure, the Drexel MDC proved to be an effective way of introducing masonry materials, design, construction, testing, and modeling of load bearing masonry walls. The competition framework and hands-on approach not only provided a unique opportunity for students familiar with traditional lectures, but also motivated learning and fostered excitement about masonry and structural/architectural engineering in general. Unfortunately, during the mid 1990s the small-scale block-making machine had aged and deteriorated to such a point that these activities were no longer possible and the Drexel MDC was stopped in 2001 once the inventory of block had been exhausted.

In the summer of 2005, Drexel University was awarded a grant from the NCMA Education and Research Foundation to re-develop the capability of producing small-scale concrete masonry units in-house. Through this grant, Drexel researchers designed, acquired and validated the capabilities of the small-scale block-making machine shown in Figure 1a. As a result of this effort, the Drexel MDC was re-instated as part of the masonry curriculum during the spring of 2006 (Figure 1b) after being dormant for five years due to a lack of small-scale block-making capabilities

The revamped Drexel MDC is founded on the three requisite components of the scientific method: hypothesis, observation, and validation. First, students design and participate in the construction of their 1/3-scale concrete masonry walls. While some guidance is provided, students are faced with open-ended decisions related to the aesthetics, geometry, extent of grouting, and placement/size/type of reinforcement. Second, students hypothesize mathematical models to predict the behavior of their walls (Figure 2a). These models range from very simplified code-type approaches to more refined simulation models using commercial finite element software. Once the predictions have been finalized, the walls are tested to failure by applying in-plane shear forces. During the tests students observe and document the response and failure modes of their walls (Figure 2b). Following the test, students compare the response data obtained with the predictions of their mathematical models in order to validate or update the various modeling assumptions made.

The judging of the competition is carried out by a panel of experts consisting of engineering and architecture faculty members, local engineers and architects, and representatives from local concrete block manufacturers and local masonry contractors. This panel of judges assigns a score (out of 100) to each entry for each of the following three subjective criteria:

(2) Innovative Use of Concrete Masonry Materials (standard use of novel concrete masonry products or novel use of standard concrete masonry products)

(3) Constructability (how well the design takes into consideration its ability to be built)

In addition to these criteria, two quantitative, objective scores will be added. The first will rank the entries in terms of structural efficiency based on their strength-to-weight ratios. These scores are generated by assigning the most efficient entry a score of 100, and the other entries a score equal to their relative (percent) strength-to-weight ratio. The second objective criteria is based on the accuracy of the strength prediction. These scores will be generated by subtracting the percent difference between the predicted and actual strengths from 100. The total score for each entry will be generated by averaging the five individual scores.

The following table summarizes the prizes for the 2007 Drexel MDC, which are sponsored by the NCMA Education and Research Foundation:

Award	Prize
Best Design – First Place (awarded to the entry with the highest total score across all judged criteria)	$1,500, up to $1,000 in reimbursed travel expenses to present the winning design at the NCMA Annual Convention, and a trophy
Best Design – Second Place	$1,000, and a plaque
Best Design – Third Place	$500, and a plaque
Best Structural Efficiency	$500, and a plaque
Best Prediction*	$500, and a plaque

* - Only entries scoring in the top 50% for Performance shall be considered for the Best Prediction award.