The Collaborative International Dictionary
Portland cement \Port"land ce*ment"\ A cement having the color of the Portland stone of England, made by calcining an artificial mixture of carbonate of lime and clay, or sometimes certain natural limestones or chalky clays. It contains a large proportion of clay, and hardens under water.
Wikipedia
Portland cement is the most common type of cement in general use around the world, used as a basic ingredient of concrete, mortar, stucco, and most non-speciality grout. It was developed from other types of hydraulic lime in England in the mid 19th century and usually originates from limestone. It is a fine powder produced by heating materials in a kiln to form what is called clinker, grinding the clinker, and adding small amounts of other materials. Several types of Portland cement are available with the most common being called ordinary Portland cement (OPC) which is grey in color, but a white Portland cement is also available.
Portland cement is caustic, so it can cause chemical burns. The powder can cause irritation or, with severe exposure, lung cancer and can contain some hazardous components such as crystalline silica and hexavalent chromium. Environmental concerns are the high energy consumption required to mine, manufacture, and transport the cement and the related air pollution, including the release of greenhouse gases (e.g., carbon dioxide), dioxin, NO, SO, and particulates.
The low cost and widespread availability of the limestone, shales, and other naturally occurring materials used in Portland cement make it one of the lowest-cost materials widely used over the last century throughout the world. Concrete produced from Portland cement is one of the most versatile construction materials available in the world.
Usage examples of "portland cement".
About five years ago a Portland cement firm came into town and began buying up the little dealers and cutting prices against the rest.
A torn and empty Hanna Portland Cement bag was found under the Porsche.
When she got the regolith cut right, she was going to lay a foundation of Portland cement, the best concrete they could make with the materials at hand.
She hurried over to him, and he saw her and stood and made straight for her and tripped again across the rough Portland cement.
Potassium, magnesium, phosphorus, Portland cement, the things we can get from sea water.
I might even have got richsmall-town rich, an eight-room house, two cars in the garage, chicken every Sunday and the Readers Digest on the living room table, the wife with a cast iron permanent and me with a brain like a sack of Portland cement.
I might even have got rich--small-town rich, an eight-roam house, two cars in the garage, chicken every Sunday and the Reader's Digest on the living room table, the wife with a cast iron permanent and me with a brain like a sack of Portland cement.
Peters's Pour Yourself a House, and two books on how to make Portland cement.
God knows I'd love to take you out of here, I'm not made of Portland cement, but if I take you the alarm bells will ring and then they'll pull the plug.