Lime and Cement Technology: Transition from Traditional to Standardized treatment Methods

Abstract

During the late eighteenth and throughout the nineteenth century masonry technology underwent a major transition, whereby, the production process increasingly absorbed techniques traditionally carried out by craftsmen. This transition also involved an increasing shift from lime technology to cement technology1. This influenced traditional work methods involving lime mortars as well as creating new methods for preparation of cement. Development of cement assisted the expansion of vital infrastructure such as roads, bridges, dams, sewers, and high-rise structures. In order to facilitate high-rise construction with cement, masonry units such as commercially produced brick were developed with similar strength and compression characteristics as cement.

Historically, lime mortar preparation involved multiple and variant treatment methods. These practices arose from generations of experimental practice, in order to determine which methods were most beneficial. Development of these skills was transferred from master to apprentice and from father to son. These treatment methods involved a calcium carbonate raw material and its conversion into a lime suitable for blending with aggregates, which resulted in a workable mortar for uniting building materials. Such lime building compounds included, stuccos, frescos, plasters, and mortars. The scope of this project involves primarily lime mortar, although treatment methods and materials are very similar for all of these five lime compounds.

Restoration of historic structures built with lime mortar creates challenges for architects, conservators, masons and all persons tasked with masonry restoration. Original masonry Materials and methods involving lime technology have been superseded by cement technology with its own materials and techniques. Cement has failed to provide a successful role as a binder for the restoration of historic structures built with lime mortar. In order to maintain the integrity of historic structures, rediscovery and application of traditional lime technology can further bridge the gap between past and present masonry mortar.