Bonus
In 2023, researchers found that the presence of lime clasts in an ancient Roman form of this material played a key role in its self-healing properties. For 10 points each:
[10m] Name this composite material. Modern preparations of this material may involve prestressing it with high-strength tendons or embedding it with rebar to reinforce it.
ANSWER: concrete [accept reinforced concrete or ferroconcrete; accept prestressed concrete; accept self-healing concrete; accept Roman concrete]
[10e] Prestressing or reinforcing concrete helps overcome its weakness to this kind of force. A rope experiences this kind of force when it is held taut.
ANSWER: tension [accept tensile force]
[10h] Concrete can also be made more workable and fluid by adding the “super-” form of these additives, reducing the water requirements of concrete production. These additives are also used to decrease the viscosity of polymers.
ANSWER: plasticizers [accept superplasticizers]
<Editors, Chemistry>
| Editions | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|
| 2 | 118 | 18.56 | 92% | 91% | 3% |
Conversion
| Team | Opponent | Part 1 | Part 2 | Part 3 | Total | Parts |
|---|---|---|---|---|---|---|
| Claremont A | UCSD B | 0 | 10 | 0 | 10 | E |
| Claremont C | UCLA A | 10 | 10 | 0 | 20 | ME |
| UC Irvine | USC B | 10 | 10 | 0 | 20 | ME |
| UCLA B | UC Santa Barbara | 0 | 10 | 0 | 10 | E |
| UCLA C | Claremont B | 10 | 10 | 0 | 20 | ME |
| UCLA D | UCSD A | 10 | 10 | 0 | 20 | ME |
| UCLA F | UCLA E | 10 | 10 | 0 | 20 | ME |
Summary
| Tournament | Edition | Exact Match? | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|---|---|
| UK (North) | UK | Y | 5 | 18.00 | 80% | 100% | 0% |
| UK (South) | UK | Y | 8 | 20.00 | 88% | 100% | 13% |
| Northern California | US | Y | 1 | 20.00 | 100% | 100% | 0% |
| Southern California | US | Y | 7 | 17.14 | 100% | 71% | 0% |
| Eastern Canada (1) | US | Y | 5 | 16.00 | 100% | 60% | 0% |
| Eastern Canada (2) | US | Y | 9 | 20.00 | 100% | 89% | 11% |
| Florida | US | Y | 1 | 20.00 | 100% | 100% | 0% |
| Great Lakes | US | Y | 12 | 17.50 | 83% | 92% | 0% |
| Lower Mid-Atlantic | US | Y | 9 | 17.78 | 89% | 89% | 0% |
| Upper Mid-Atlantic | US | Y | 12 | 20.00 | 92% | 100% | 8% |
| Midwest | US | Y | 9 | 17.78 | 89% | 89% | 0% |
| North | US | Y | 1 | 20.00 | 100% | 100% | 0% |
| Northeast | US | Y | 12 | 20.00 | 100% | 100% | 0% |
| Pacific | US | Y | 9 | 17.78 | 89% | 78% | 11% |
| Southeast | US | Y | 13 | 17.69 | 85% | 92% | 0% |
| Upstate NY | US | Y | 5 | 20.00 | 100% | 100% | 0% |