Tuesday, June 25, 2019

Cement vs concrete vs mortar.



Oh Man, this whole time I thought Portland cement was named after Portland Oregon because the first time I heard of it was in Vancouver. 

Not so. It was invented by a guy in Britain, Joseph Aspdin, in early 19th century and developed further by his son mid 19th century. Wikipedia.

Elsewhere in comments some guy said "... and they (China) even invented it (cement)!" He was talking about China needing the United States to build a cement factory for a large concrete project because at the time they didn't have one. That didn't sound right because I saw on t.v. a show about the Romans discovering a way of combining lava rock and sea water to produce a concrete that cured underwater. And that changed everything. They could build piers and docks in ports where that was previously impossible. 

I responded with a link to this page: The History of Concrete, and that link has received a number of "likes." That made me think you might like it too. The history goes back a lot longer than you might think. But that's concrete by expanded definition.

A l-o-o-o-n-g time ago I was watching Tom Baker era Dr Who with traveling companion Romana II. She was such a snappy wit. Dr Who asked Romana if she knows the difference between cement and concrete and without pause (because it was in her script) she answered something like "Cement: Tricalcium and dicalcium silicate, tricalcium aluminate, tetracalcium aluminoferrite, gypsum.  Concrete: cement, sand and aggregate." But I forget exactly. She listed the chemical compositions but left out water. Those Baker episodes are filled with little gems like this.


And I was sitting there watching and thinking, "Wow, there's a difference?"

2 comments:

ken in tx said...

My Civil Engineering brother taught me, Cement is to Concrete what Flour is to Bread.

XRay said...

He taught you well.