## This ain’t your first rodeo. Wrangle concrete and steel together.

Competition Date: March 2, 2018

Technical Paper Due: February 16, 2018

Time: On Sched

Location:”The Pit” Weil Hall 1st floor

Rules: Reinforcement Rodeo *Updated 1/28/18 with important formula change*

Formula Derivation: Proof and Explanation

Technical Paper Rubric: Technical Paper Rubric

Mix Design Format: Updated Mix Design Format

Technical Paper Submission Procedures:

- Electronic submission is now closed.

Concrete Cylinder Submission Procedures:

- Bring 3 2×4 inch concrete cylinders to “The Pit” in Weil Hall between 8:00 AM and 9:00 AM, March 2.

Post Test Calculation:

- Please come to Post Test Calculation with
- One (1) single sided sheet of notes
- Two (2) calculators
- Writing Utensils
- Pad of Engineering Paper

## Updated Formula

# Q&A

## Updated 12/3/17

**Rule Change: Cylinder Size Change – An issue arose with our testing apparatus. Cylinders should be 2 inch x 4 inch cylinders instead. We apologize for this late change.** Additionally, Please note: Assume f’c = f’cr = average compressive strength of concrete samples in PSI

**10/18/2017**

Do teams construct a 30′ beam?

Teams DO NOT construct a 30′ beam. They complete a design report, perform calculations, and create a concrete mix as if they are designing a 15′ beam. Teams only construct 3 sample concrete cylinders. Those cylinders will be tested on site and calculations of the theoretical beam will be performed again to determine the actual beam strength.**11/20/2017**

With a 30′ beam, it seems as if negative values are calculated with reasonable inputs.

We apologize for the confusion. It seems a 30 ft beam is too long. We are adjusting the beam dimensions to**15**feet long which changes the formula to:

Available Load =~~(d-(180/(0.85*f’c*b)))/1.875 – (W*144)/((d/12)*(b/12))~~(See #8 below)

*The discrepancy has been fixed on the document pdf 12/2/2017***11/20/2017**

What is the size requirements for the concrete cylinder for this competition?

We are requiring teams to submit 3 cylinders which are~~3~~2 inch x~~6~~4 inch.**Update on 11/20/2017***The discrepancy has been fixed on the document pdf 12/2/2017*

**11/7/2017**

For the bonus points, what is considered justified proof of using locally procured materials?

We aren’t limiting what the proof is for locally procured materials. The proof must substantially show that the material was both produced and procured within 300 miles of your campus. An example of the proof would be a statement from the producer of the location of their plant plus a bill of lading showing the shipping location either at the plant or another location within 300 miles of your campus. If you have any questions regarding your proof, feel free to submit another RFI with the documents you plan on submitting and we will review them.**11/26/2017**

Please advise on the proper breakdown of the scoring procedure. Under Section 6 on the rules, Scoring is listed as follows: Beam Strength: 50%, Pre-Test Strength Prediction: 10%, Post-Test Calculations: 10%, and Technical Paper: 30%. However, under the “Competition Scoring” category, Beam Strength is listed to be 60%, Pre-Test Strength Prediction is listed to be 15%, Post-Test Calculations are listed to be 5%, and Technical Paper is listed to be 30% of the total score.

The Scoring procedure will be as follows: Beam Strength is 50%, Pre-Test Strength Prediction is 15%, Post-Test Calculations is 5%, and Technical Paper is 30% of the total score. *The discrepancy has been fixed on the document pdf 12/2/2017***12/2/2017**

**When is the technical paper actually due? it is stated on the website that it’s February 16**The website states the correct date. The technical paper is due^{th}, whereas the PDF says it’s February 9^{th}.

*The discrepancy has been fixed on the document pdf 12/2/2017***February 16th.**

**12/2/2017**

Section 4 states “After the beams are tested, teams will be asked to calculate their post-test available load with tested strength and dimensions”. To clarify: After the concrete cylinder samples are tested using ASTM C39, teams will be asked to calculate their post-test available load of the theoretical beam with tested strength from the concrete cylinders and dimensions designed (b, h, and d). These calculations will be similar to your teams pre-test calculation presented in the Beam Design Report but include the actual concrete f’c value and unit weight of the tested concrete cylinder sample.**Which beams in section 4 are the post-test calculations referring to?**

**12/3/2017**

We apologize for the confusion and multiple changes on the calculation.**Calculation Update**

~~The updated formula is: 64000*(d-(52941/(2*f’c*b)))-(W*144)/((d/12)*(b/12))~~The updated formula is available in the current rules (1/28/18)**12/3/2017**

**Do we need to take into account the statistical difference between f’c and f’cr?**

No, Assume f’c = f’cr = average compressive strength of concrete samples in PSI**1/17/18**

**What is the deal with this competition?**

The only thing you’re allowed to change is the height (up to the maximum) and the width of the beam (up to max). The steel and the length are constant. Weight gets calculated as part of the score so – you want to optimize the height/weight. You will give us a projection of what you think your concretes strength and how much your “designed beam will hold”(calculate this beforehand) Then we get the actual strength of the concrete and you recalculate the beam strength at the competition.**1/19/2018**

**How do we report fibers in the concrete mix?**

We have included the Fibers in the mix table.**1/23/2018 A few considerations specified to avoid confusion**

No factoring is to be considered

f = 1.0 : use nominal strengths calculations (Mn), not design strength (fMn)

Do not apply load factors to applied loads or self weight

The design needs to demonstrate a ductile section (steel strain >= 0.005)

The design needs to demonstrate minimum steel requirement is met (reinforcing ratio r = As/bd > minimum allowed for flexure)

Designed section must be rectangular**1/23/18 Updated Formula**

Please view PDF- 1
**/23/18 Want to see how we confirmed the equation?**

Please view PDF for the worked solution

**1/23/18 Given that aggregate must pass the No. 8 sieve, is this considered mortar, and not concrete?**

We are referring to this as concrete in the sense that it contains cement, aggregate, and water. Please refer to the rules for allowed materials and do not assume that certain materials are allowed due to the fact that it is called concrete.**1/23/18 For the “Post-test Calculations” are we allowed to just use the same formula as provided by the host school used to judge the Available load?**

Yes, please use the provided formula.

**1/28/19**

**Do you think you could update the website with the updated mix table on the Reinforcement Rodeo page?**

The updated mix table is now uploaded.