ACI Concrete Cylinder Competition

REGISTRATION FORMS:
Part 1: Online Advance Registration Form - CLOSED 
This form must be received before midnight EST on Monday, October 6, 2008

Part 2: Official Mix Design and Testing Forms - CLOSED
These forms must be received before midnight EST on Monday, October 20, 2008

Commonly Asked Questions

2008 Concrete Cylinder Winners

2006 Concrete Cylinder Winners

2005 Concrete Cylinder Winners

Objectives     

To produce concrete cylinders with an average compressive strength of 7,000 psi (48.3 Mpa) and a saturated surface-dry density of 150 lb/ft³  (2.39 kg/l) with the highest cementitious efficiency and the lowest cost.

To produce a written report of no more than 500, 12-point font, double-spaced, words with charts and pictures explaining the design and production process.  How were the initial trial batch proportions established?  These might be based on ACI 211, previous experience, or other resources.  How were the trial batch results evaluated and what rationale was applied to modify the mix proportions?  For at least the first iteration explain how the design was brought closer to the design requirements.  How many trial batches were required to produce the ultimate design?  What are the predicted strength and density results?  Consult ACI 211 on submission of the final mixture proportions.  The report is separate from the Excel Official Mix and Testing Forms.  Please note that the second worksheet in Excel file is set-up to assist in the computation of cost, strength, and density.  The input cells are highlighted with light yellow shading.

Prizes      

First, Second, and Third place awards will be given in the following categories: target strength, target density, cement efficiency, cost and overall.  The report score will be used to determine the overall winners. (Please reference section 5b for scoring.)  The First Place team in each category will receive a $300 award, the Second Place team will receive $200, and the Third Place team will receive $100.  Additionally, each winner will be recognized in Concrete International magazine if space allows and on ACI's website.

Rules      

1. Eligibility

1. Team members must be high school, technical school, trade school, or college undergraduate student(s) when the cylinders are cast.  Each school is limited to two teams.  Each team makes one entry (an entry is made of three cylinders of the same batch as explained in Section 4).
2. A team is limited to five individuals.  A student may not be a member of more than one team.
3. The supervising faculty member is professionally responsible for assuring compliance with the rules and must sign the entry forms. A faculty member may supervise more than one team.

2. Material

1. The concrete used to cast the cylinders must use cementitious materials as binder, as defined in Section 2b.  Chemical admixtures meeting ASTM C 260, C 494, or 1017 may be used.
2. The cementitious materials shall be limited to portland cement meeting ASTM C 150, blended cement meeting ASTM C 595 and C 1157, and expansive cement meeting ASTM C 845. Supplementary cementitious materials such as fly ash and natural pozzolan meeting ASTM C 618, silica fume meeting ASTM C 1240, and slag meeting ASTM C 989 may also be used. The maximum amounts of these materials or combinations of these materials will be as stipulated in ACI 318 Table 4.2.3.
3. The coarse aggregate and fine aggregate should comply with ASTM C 33 and C330.
4. Use only the materials and testing listed in the Official Mix and Cost worksheets.

3. Specimen Preparation

1. The plastic concrete shall exhibit a slump of 6 in (150 mm) + 2 in (50 mm), measured by ASTM C 143.
2. The plastic concrete shall exhibit an air content of 6% + 1.5%, measured by ASTM C 231.
3. The standard specimen shall be a 4 x 8 in (or 100 x 200 mm) cylindrical specimen prepared in compliance with ASTM C 31.  
4. Specimens shall be standard laboratory cured in accordance with ASTM C 31.
5. Each specimen shall be labeled on the side with a permanent marker.  Identify the school name/abbreviation, team name/number and cylinder number/letter.

4. Specimen Testing 

1. The compressive strength will be tested in compliance with ASTM C 39 utilizing ASTM C 1231 unbonded caps.  The compressive strength will be computed as the average of two test cylinders.  The compressive strength of each cylinder shall not deviate from the strength of the other cylinder by more than 700 psi (4.85 Mpa).  A third cylinder can be tested to meet this qualification.  Failure to meet this qualification will disqualify the test.  In this case a score of 0 will be assigned for compressive strength and cementitious efficiency.
2. The saturated surface-dry density will be the average of two cylinders using values measured by multiplying the SSD bulk specific gravity determined using method of ASTM C 127 by a value of 62.4 lb/ft³ (1 kg/L).Contestants should take measures to assure that the specimens remain in the SSD state.  For example, wrap them in a wet paper towel and seal them in a plastic bag for transportation.  The measured density will be compared to the theoretical density.  Deviations of more than 5 lb./ft.³ (0.08 kg/L) will score zero in the cementitious efficiency and cost categories.
3. The compressive strength must be at least 6,300 psi to qualify for the lowest cost category.  Inadequate strength will result in a score of 0 for the lowest cost category.

5. Scoring

1. The strength and density will be scored for how close the measured values are to the specified values.  The cost will be the sum of the costs of the individual materials, priced at contest assigned costs (page 2 of Excel Official Information Form).  The cement efficiency will be the compressive strength divided by the total amount of cementitious material in one cubic yard of mix for a result in psi/# cement per cyd.  The reports will be given scores of 5 (excellent), 4 (very good), 3 (good), 2 (fair) or 1 (poor) based on the option of the panel of NJACI appointed readers.
2. The following formula will be utilized to compute the final score:
   
   

6. Judging

1. Testing will take place at the 2008 ACI International Fall Convention in St. Louis, MO on Sunday, November 2, 2008 starting at 1:00 PM.
2. The Chair of Committee E 801 will appoint the judges.
3. The judges will make the final determination of compliance with the rules and penalties for rules violations.  Incomplete submissions may disqualify entries.
4. The decision of the judges will be final, and appeals will not be considered.
5. Advance registration is required.  All contestants must submit an Online Advance Registration Form for each entry on the ACI website at www.concrete.org.  All advance registrations must be submitted by midnight EST on Monday, October 6, 2008. 

7. Submitting the Cylinders and Supporting Materials

The Official Mix Design and Testing Forms along with the written report must be submitted to students@concrete.org by Monday, October 20, 2008.  The report must be sent as a Microsoft Word document and the Mix Design and Testing Forms must be sent as Microsoft Excel spreadsheets.  Formats other than Word and Excel will not be accepted.  Failure to meet this deadline will result in a score of zero for the report.  These forms are used in scoring the competition.  They must be correct and are subject to verification.  Incorrect forms may lead to disqualification from the competition.  The cylinders, accompanied by hard copies of The Official Mix Design and Testing Forms and the written report are to be submitted in person by 11:00 a.m. on the day of the competition.  Cylinders arriving after 11:00 a.m. will not be allowed to compete and will only be tested after the competition is complete, should time permit.  The individual bringing your cylinders to the competition does not have to be a member of your team.

8. Compliance with ACI-Concrete Cylinder Competition Rules

ACI reserves the right to perform detailed examination and check entries for compliance with the competition rules. Due to the complexity of this task, the examination may be done after the competition. If the examination shows that a team did not follow the rules, the team, their advisor and all his/her teams will be disqualified. ACI Committee E 801 will further document recommendations to sanction the team, their advisor, and/or school/university participation in future competitions.

9. Contact Information

Please see the main Student Competitions page (subtitle: Response to Inquiries) for details on how to submit technical questions for all ACI Student Competitions.  For questions regarding registration please contact:

Lacey Jones
American Concrete Institute
38800 Country Club Dr
Farmington Hills, MI  48331
Fax: (248) 848-3801
E-mail: students@concrete.org