FRC Bowling Ball Competition


The objective of this competition is to demonstrate the benefits of fiber use in concrete, to gain experience in forming and fabricating a fiber-reinforced concrete element, and to provide a means to practice for the national competition in Salt Lake City, Utah in March. Each team will design and fabricate a fiber-reinforced bowling ball.


The competition will take place at the ACI IL facility in Elmhurst, IL on 10 February 2018 beginning at 9am. Lunch will be provided. The results of the competition will be evaluated with the winning teams awarded at the ACI IL dinner meeting at the Erie Café in Chicago on 21 February 2018. Teams and advisors are invited and welcome to attend – registration for the dinner is on the ACI IL webpage.

Competition and Prizes

The Local Competition has a single prize category. Fiber-reinforced bowling balls will be tested for size and density, the ability to be used successfully as bowling balls, and post-crack load capacity (toughness). The winning team will be awarded a prize of $750 to help offset their costs in representing the IL Chapter at the National Competition in Salt Lake City Utah in March. The prize will be awarded at the ACI Dinner meeting on 21 February 2018.

Student team

2 teams per school are eligible for this local competition. All members of a given team must be from the same school. A team is limited to two to eight students currently enrolled in a high school or an undergraduate college or university program. Undergraduate students on cooperative or internship work assignment are eligible to compete. Each team must have a supervising faculty advisor who will see that the team complies with the rules of the competition.

At least one individual (faculty advisor or student team member) must be present at the competition for each of the bowling ball tests.

Materials and curing

Curing shall be at atmospheric pressure. The curing temperatures shall not exceed the boiling point of water. Use of a standard moist-curing room is permitted.

The bowling ball must be made from a fiber-reinforced concrete mixture. Fiber suppliers from the committee are listed on the main competition rules page for the ACI national competition. Also, fiber manufacturers are listed in the Fiber Reinforced Concrete Association. The fiber-reinforced concrete mixture design shall include fibers meeting their respective ASTM specification. The maximum length of the fiber is 60 mm. The fibers may be used at any dosage and volume fraction. No other type of reinforcement is allowed.

Only the Mixture materials listed in the Design Example can be used. The Mixture materials are to meet ASTM standards listed as applicable. No other Mixture materials are allowed. Filler materials are not considered Mixture materials and are not subject to the same limitations as the rest of the mixture materials. Not all the materials listed are required to be used.

Filling of honeycombed surfaces after casting is allowed. Filling materials must be selected from the same materials used in the original concrete mixture. Latex based paints are listed and allowed, though are not required.

The bowling ball may have layers or be solid (homogeneous) or core-filled. The use of bowling ball filler is optional and up to 2 separate core-filler materials is allowed. Expanded polystyrene beads are acceptable filler. Another acceptable filler is made of primarily 1 material (for example, a rubber balloon). Report the materials used and the total volume of the filler used on the mixture sheet.

Bowling ball competition

Each team shall bring a single ball for the competition and testing at the competition. The ball should be marked with the team’s name and the marking should be at least 10mm in height. The judges may apply a penalty if a team’s ball is disqualified during either the Mass Test or the Diameter Test and allow them to continue with the competition.

Mass Test (10%)

The bowling ball mass shall not exceed 5.5 kg. The judges shall weigh each ball to verify that it meets the mass requirements. All balls will be weighed using the same scale of the judges’ choice. The actual mass of the bowling ball in kg will be the mass test score carried through to the evaluation phase of the competition.

If the ball weighs more than 5.5 kg, it shall be disqualified.

Diameter Test (15%)

The bowling ball shall be spherical and shall measure 200 ± 15 mm diameter. Each ball that meets the Mass Test will be measured along three different axes arbitrarily selected by the judges for adherence to the bowling ball diameter consistency requirements set forth in these rules. Three specific diameter measurements will be recorded (in millimeters) as the scores for the diameter test to be carried through to the Evaluation Phase of the competition.

If any of the diameter measurements of the bowling ball are greater or less than the design standard tolerance, the ball shall be disqualified.

Modification of entries shall not be permitted once they are accepted for the competition. If a team fails both mass and diameter tests, the judges may allow the team to continue in the competition but are not required to do so.

Bowling Test (30%)

The bowling apparatus (ramp and alley) will be provided at the competition. One and only one team member can be identified as the “Team Bowler” and another team member will retrieve the bowled ball and return the ball to the Team Bowler. The Team Bowler, with no assistance from any other members of the team, will position the test ball at the top of a V-shaped ramp and release it down the ramp onto a flat, non-oiled, hard-surfaced lane. The Ramp is approximately 1500 mm long, 670 mm wide, and 620 mm in height to achieve a reasonable ball speed. The bowling lane (or alley) will be approximately 1000 mm wide and 4000 mm long or longer.

Each team will “roll” and score modified frames of bowling. Six standard-sized bowling pins will be used and will be positioned and spaced in a pattern chosen by the judges. During the day of the competition, the judges will decide these details based upon the total number of teams for the competition:

  • 1-Pin arrangement,
  • 2-How many rolls per frame,
  • 3-How many frames will be bowled, and
  • 4-Whether horizontal adjustments to the ramp for aiming the ball will be allowed.

The team’s score at the completion of the number of frames selected for the competition by the judges will be the Bowling Test Score to be carried through to the Point Evaluation Phase of the competition.

The inclined ramp must be used to deliver the ball. Under no circumstances is the ball to be thrown, launched, or catapulted down the alley toward the pins. If the bowl rolls off the side of the alley prior to striking the pins, it is considered a gutter ball and no pins will be scored for that roll. Once the bowling ball is released and begins its descent down the incline, the ball may not be chased after or interrupted as the ball is rolling. Ball return will be by another team member. No running or walking fast or throwing the balls as a return. The resulting pin count will be recorded as the score for that ball. The judges will be responsible for setting the pins and recording the score.

Further, judges will have the right to control the time for the bowling by imposing a time limit for the bowling portion of the competition to ensure that not too much time is spent aiming or adjusting for the ball roll or a maximum amount of time to accomplish the amount of rolls for the chosen number of frames. In this case and if the total allowed number of rolls are not completed at the expiration of the allowed time, the score attained during the time limit will be the team’s bowling score.

Toughness Test (20%)

The test ball will be placed in a testing apparatus for controlled crushing. During the day of the competition, the judges will decide the displacement rate based upon the total number of teams for the competition. The displacement rate will be set between 5.00 and 12.50 mm per minute. The load will be recorded for every 5 mm of crosshead displacement and the average of the five loads will be computed. The average load for these five displacement points will be the Toughness Load Test Score to be carried through to the Evaluation Phase of the competition, with the team achieving the highest toughness earning maximum points.

Load Test (25%)

The load will be applied until the crosshead displacement of the testing apparatus has traveled 25 mm. The load at 25 mm is considered the Final Deformation Load and the team with the highest final load will receive maximum points. This load is considered the Final Deformation Load Test Score to be carried through to the Evaluation Phase of the competition.


A score will be awarded to each bowling ball for design and analysis. These scores will be converted into competition points based on relative importance and a 100-based score. The team rankings will be based on the number of competition points earned as a result of the bowling ball design and analysis. The 5 bowling ball tests and score percentages are listed and summarized with test intent.

  • 1 - Mass Test (10%): Produce each ball with the highest mass without going over the 5.5 kg limit.
  • 2 - Diameter Test (15%): Produce a consistent spherical shape of each bowling ball.
  • 3 - Bowling Test (30%): Score the highest in six-pin bowling rolled during the convention.
  • 4 - Toughness Test (20%): Maximize the average value of the applied load at the five deformation points.
  • 5 - Load Test (25%): Maintain a high load at a 25 mm deformation.


The local chapter will select judges as needed. The judges will determine whether or not the rules have been followed. The decision of the judges will be final, and appeals will not be considered. The judges retain the right to use any means or method they feel are necessary to verify and enforce the rules and requirements of the competition. The judges retain the right to interpret, modify, or eliminate any section or sections of these rules as special circumstances arise. Judges may allow teams to compete that are ineligible for prizes.

Rules compliance

ACI IL reserves the right to perform detailed examination and check entries for compliance with the competition rules. Examination may also be done after the competition. If examination shows that a team did not follow the rules, the team and their advisor may be disqualified.

Competition Inquiries and Registration

Please address rules questions for clarification to Include “ACI IL Bowling Ball Competition” in the subject line. Registration is requested to Walt Flood at by 8 February. Include “ACI IL Bowling Ball Competition” in the subject line.

NOTE: Revised 2 January 2018 for updated competition date and prize amount