RESTRUCTURING

Until approximately 1900, lime putty was used in construction applications. Limestone was burned in small kilns often built on the side of a hill to facilitate loading(ref. vii). Wood, coal and coke were used as fuel. The quicklime produced from these kilns was added to water in a pit or metal trough and soaked for an extended period of time. The time required for soaking was dependent on the quality of the quicklime and could range from days to years. It was generally thought that the longer the quicklime was soaked, the better it would perform. The Standard Specification for Quicklime for Structural Purposes was developed in 1913. After the turn of the century, the use of hydrated lime products began. Water was added to quicklime at the manufacturing plant to reduce the amount of time required for soaking at the jobsite. In the late 1930's, the production of pressure hydrated dolomitic lime products began. These products required only short periods of soaking (20 minutes or less) prior to use. In 1946 the Standard Specification for Hydrated Lime for Masonry Purposes  This standard identified two and later four types of lime products that could be used in masonry applications.