论文简介： It is much easier to lay blocks and bricks with mortar joints than to cut them to fit precisely with dry joints. Today, mortar is usually made from sand, portland cement, and some additives, but, prior to the late nineteenth century, mortar usually consisted of sand and lime. Since lime is water-soluble, the mortar joints were a common source of weakness in stone and brick structures. Gypsum was used as mortar in Egypt, and naturally occurring bitumen in Mesopotamia.
It is much easier to lay blocks and bricks with mortar joints than to cut them to fit precisely with dry joints. Today, mortar is usually made from sand, portland cement, and some additives, but, prior to the late nineteenth century, mortar usually consisted of sand and lime. Since lime is water-soluble, the mortar joints were a common source of weakness in stone and brick structures. Gypsum was used as mortar in Egypt, and naturally occurring bitumen in Mesopotamia.
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