The Chemistry of Bricks


YouTube Video

Bricks are fundamental for construction and as test of strength, speed and skill. For a long time the art of breaking has been used in the martial arts to demonstrate one's level of skill with a technique. If one does not have sufficient skill when attempting a break, they are more likely to break their own bones instead of the material. I have been in the martial arts for nine years now so I have a pretty good understanding of how to to break, but what they don’t teach you in the martial arts is the chemistry of the break. What chemistry enables you to break the brick and not your bones? It turns out there is some very complicated chemistry going on in the brick. On this page I will do my best to show the chemistry of bricks.

Composition of ...
  1. Tricalcium silicate (Ca3SiO5 or 3CaO.SiO2)

  2. Dicalcium silicate (Ca2SiO4 or 2CaO.SiO2)

  3. Tricalcium aluminate (Ca3Al2O6 or 3CaO .Al2O3)

  4. Tetracalcium aluminoferrite (Ca4Al2Fe2O10 or 4CaO.Al2O3.Fe2O3)

  5. Gypsum (CaSO4.2H2O)

  6. ettringite (Ca6Al2(SO4)3(OH)12)

Main Chemicals, Compounds, Components

  1. Water

  2. Cement

Chemistry's Role

Each of the chemicals listed in the composition undergoes a hydration reaction when mixed with water.

Ca3O5Si + 2H2O    -->    2 CaO +  SiO2 +  H2O +  Ca(OH)2   ∆H=-250J/g   → The hydration reaction of Calcium Silicates

       gypsum↓                            ettringite↓

Ca3Al2O6+CaSO4.2H2O+H2O →  Ca6Al2(SO4)3(OH)12·+26H2O

Ca4Al2Fe2O10+ C6(A,F) Š3H32 → 3C4(A,F)ŠH12 + (F,A)H3 → the hydration reaction of Calcium Aluminoferrites

Background Research

Cement bricks are made by mixing water and cement and the pouring the mix into a mod and wait for it to dry. Bricks are mainly used in construction but are also used in the martial arts.


How Portland cement is made and some of it properties.

How cement is proportioned and how that affects the quality.

An overview of the history of cement.

The Hydration reactions.

The composition of cement.

A description of the human hand and wrist

the composition of Bones

the physics of breaking bricks. (may not be relevant but could be useful)

About the Author

Rhys Sunderland is a junior at Senior High School in Billings, Mt. He has a 2nd degree black-belt in Chi-Tu-Do, and a 1st degree black-belt in Shiho-Karano Jiu Jitsu. He plans on joining the Marines after high school and then going to college for an Engineering degree. After getting a degree, he plans on re enlisting in the marines in hopes of becoming a fighter pilot.