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Objectives Teams are challenged to apply sustainability concepts and to use their knowledge of concrete mixture design by producing pervious concrete which balances permeability and splitting tensile strength. Teams are additionally challenged to develop a mixture design which demonstrates cementitious efficiency; i. Only teams judged to have a complete and accurate mix design are eligible for inclusion in the Cementitious Efficiency prize category.
Results will be announced and prizes awarded at the student lunch, the day following the competition. Each school shall be eligible for only one prize per category.
Resources This competition uses a falling-head permeameter method, see Figure 1. Rules These rules have been approved only for the Fall competition, a PDF copy can be accessed here. Read more. Eligibility Team members shall consist only of high school, technical school, trade school, or undergraduate college or university student s at the time of cylinder casting.
Undergraduate students on cooperative or internship work assignment are also eligible to compete. All members of a team shall be from the same school. Each school is limited to a single team.
A team is limited to eight individuals. A student may not be a member of more than one team. Each team shall submit a single entry into the competition. Each entry is comprised of two pervious concrete cylinders, one electronic Report, and one Official Mixture Design spreadsheet as defined below.
Each team shall have a supervising faculty advisor. The advisor shall be professionally responsible for assuring compliance with the rules of the competition and shall sign the entry forms. Faculty advisors may supervise more than one team. At least one individual faculty advisor or student team member must be designated to represent each team and be present during the cylinder testing at the time and location specified for this competition.
Participation by additional team members and school members is both permitted and encouraged. Only materials listed in the Official Mixture Design spreadsheet and described below shall be used. Mixtures shall be proportioned to result in a pervious concrete material meeting the definition of pervious concrete according to ACI R. A gradation ASTM C shall be performed of the individual aggregates or final combination of aggregates.
A report of which is required as part of the report submittal. Mixes shall use cementitious materials as a binder. Epoxies, glues, and similar binders shall not be used. Other binders will be considered by the judges on a case-by-case basis. As such, their use would not be acceptable in this competition and their use may result in disqualification or a penalty. Fibers with a maximum length of 64 mm 2. Steel fibers shall not be used. Fiber materials may be mixed that is, hybrid fibers and any dosage rate may be used.
No other type of reinforcement may be used. Cylinders shall be cured at atmospheric pressure and curing temperatures shall not exceed the boiling point of water; steam curing shall not be used.
Please note that cylinders must be in a dry condition prior to submission at the competition see Section 3. This may affect the curing methods selected. Cylinder Configuration Each entry for the competition shall consist of two cylinders. One cylinder will be tested during the competition and both will be kept for verification of compliance with the competition rules if needed. See Section Cylinders shall be submitted to the competition site in a dry condition that is, as close to oven dry as reasonable.
Teams are cautioned that submitting wet cylinders is disadvantageous. Cylinders will be submerged in water for a minimum of 30 minutes prior to testing once their dry weight is obtained. The dry weight may be used as a tool for mixture design verification.
Cylinders shall be mm 4 inches in diameter with a tolerance of plus or minus 3 mm 0. It is recommended that the mm length be obtained by cutting approximately 25 mm 1 inch from each end of a standard mm long cylinder i. The cylinders shall have flat and parallel surfaces at right angles with perpendicular sides and no indentations, cupped edges, fins or other features to bias water flow over the specimen.
Cylinders shall be homogeneous that is, have the same composition and porosity throughout the cylinder and shall not have been cut from larger sections except as required in Section 3. The marked surface will be considered the top of the cylinder and placed upwards during permeability testing. Painting or otherwise coating the cylinders is not permitted.
Modifications to cylinders are not permitted once submitted for the competition. Report Teams shall electronically submit a report meeting the requirements listed in this section for the judges to review and score in advance of the competition. The electronic version of the report shall be submitted prior to the competition as described below in standard PDF format. The electronic report due date is indicated in Section 9 below. Teams are strongly encouraged to bring a hard copy version of the report to the competition for display during the competition and general display for the ACI attendees.
Teams failing to submit the electronic version of the report including the mix design as required shall receive a score of 0 in the Performance Score equation given in Section 7. Each report shall be in the English language and contain the following. Include a copy of the gradation test results ASTM C for the individual aggregates or combined aggregates as mentioned in 2. Attach a submittal sheet for each chemical admixture used in the mixture—these are easily obtained from the manufacturer and will confirm compliance with rule 2.
The entry with the highest score shall receive the top ranking for the report section in the Cylinder Performance prize category. In addition to the PDF report above, the mixture design spreadsheet must also be submitted in Excel format. To qualify as a complete mixture design for inclusion in the Cementitious Efficiency Prize Category, the concrete mixture shall total 1. Weights and volumes shall be related with appropriate material specific gravities used.
As part of the Official Mixture Design Spreadsheet, the second tab can be used to convert a concrete design in US units totaling As this is pervious concrete, be sure to remember that a rather large portion of the concrete mix volume should be void space. Cylinder Performance Prize Category The judges will inspect both pervious concrete cylinders prior to testing to verify compliance with the rules including dimensional and material requirements.
Both cylinders shall comply with the rules and be made from the same batch of concrete, see Section The judges will randomly select one of the cylinders for testing. All tests shall use the same cylinder. Permeability Test: All cylinders will be submerged in water, once dry weight has been obtained, for a minimum of 30 minutes. The cylinder selected for testing shall be removed from the water when prepared for testing. The cylinder shall be prepared for testing by the judges. Cylinders will be wrapped with a pvc shrinkwrap for testing.
Specimens awaiting testing will be returned to the water bath until being placed in the testing apparatus. Each entry will be tested for permeability using a falling-head permeameter test setup; see Fig. With the valve closed, water shall be poured into the graduated cylinder above the cylinder until the water level remains steady at mm 9 in. Time begins when the valve is opened. The test is complete and time is stopped when the water level in the graduated cylinder reaches 25 mm 1 in.
The maximum time limit for the test shall be seconds, after which the water level above the cylinder is recorded. Teams failing to meet the maximum time limit shall be placed in descending order based on the lowest water level and ranked below the entries completing the test within the time limit.
The entry with the highest measured permeability shall receive the top ranking for the permeability test section of the Cylinder Performance prize category. Cementitious Efficiency Prize Category Only teams judged to have a complete and accurate mix design according to 4. Teams shall fully complete the Official Mixture Design spreadsheet. The spreadsheet shall be submitted by the deadline indicated below in Microsoft Excel file format. The Official Mixture Design spreadsheet will be reviewed by the judges for accuracy and compliance with the rules.
Unresolved discrepancies shall be grounds for disqualification, see Section Each entry will have its Cementitious Efficiency Score calculated. The load shall be the splitting tensile strength determined in Section 5d.
Concreto permeable : ACI 522R-06
522R-10 Report on Pervious Concrete (Reapproved 2011)
Pervious Concrete Cylinder Competition