Mortars history

A brief overview of mortar history is required to understand the historic context of the natural cement era. Mortar history begins 4000 years ago in ancient Egypt where the oldest known durable mortars were produced using a gypsum plaster with low-fired lime impurities [1]. 

It was not until the mid-18th century that English engineer John Smeaton began to experiment using other materials with hme. In particular, he discovered that clay impurities in limestone produced hydraulic properties, allowing these mortars to set under water and to resist deterioration from water exposure. This represented an important difference from simple Ume mortars and a pivotal point in mortar history. In the course of time it would have a great effect on constmction practices both in Europe and the soon to be independent colonies of America. 

Although the use of simple diluents and adulterants almost certainly predates recorded history, the use of fillers to modify the properties of a composition can be traced as far back as eady Roman times, when artisans used ground marble in lime plaster, frescoes, and po22olanic mortar. The use of fillers in paper and paper coatings made its appearance in the mid-nineteenth century. Functional fillers, which introduce new properties into a composition rather than modify pre-existing properties, were commercially developed eady in the twentieth century when Goodrich added carbon black to mbber and Baekeland formulated phenol— formaldehyde plastics with wood dour. 

Hydrocarbons were first used in the field of medicine by the Romans. Bitumen was used in ancient Mesopotamia as mortar for bricks, as a road constmction material, and to waterproof boats. Arabia and Persia have a long history of producing oil. 

Roofs are a basic element of shelter from inclement weather. Natural or hewn caves, including those of snow or ice, ate early evidence of human endeavors for protection from the cold, wind, rain, and sun. Nomadic people, before the benefits of agriculture had been discovered and housing schemes developed, depended on the availabiUty of natural materials to constmct shelters. Portable shelters, eg, tents, probably appeared early in history. Later, more permanent stmctures were developed from stone and brick. SaUent features depended strongly on the avadabihty of natural materials. The Babylonians used mud to form bricks and tiles that could be bonded with mortars or natural bitumen. Ancient buildings in Egypt were characterized by massive walls of stone and closely spaced columns that carried stone lintels to support a flat roof, often made of stone slabs. 

She developed a special interest in the history of pharmacy, and became a world authority on historical drug jars and mortars. Lothian was the first woman to be elected member of the Academie International d Histoire de la Pharmacie. In 1967, she married G. R. A. Short, a Fellow of the Pharmaceutical Society. 

Occasional repointing of the mortar joints is normally the only maintenance required. In the dilution zone, where attack of the Portland cement mortar may occur, repointing with a polyester or vinyl ester mortar will usually solve the problem. If voids are detected in the wall, these can be filled by pumping a port-land cement mix or a catalyzed resin into the wall by the technique described for filling voids in a digester lining. The service and maintenance history of these vessels has generally been excellent. 

The original EDS-1 proved its worth in a series of field operations in the continental United States. The sites included Rocky Mountain Arsenal, Colorado (10 GB bomblets) Camp Sibert, Alabama (one CG mortar round) and Spring Valley in Washington, D.C. (15 mustard agent HD artillery rounds). One EDS-1 and two EDS-2s have been used in the ongoing project to destroy 1,220 recovered chemical munitions at Pine Bluff Arsenal (PBA), Arkansas, as described below. To update the history of EDS units, operations since 2004 are tabulated in Table 3-6. 

The history of the research and development of polymer mortar and concrete is relatively short compared to that of polymer-modified mortar and concrete. The early research and development of the polymer mortar and concrete were done mainly in the Soviet Union (Russia) [8], the United States [9], West Germany [10] and Japan [11] in the late 1950s to the early 1960s. 

The history of the research and development of polymer-impregnated mortar and concrete is the shortest of the concrete-polymer composites. The process technology for the polymer-impregnated mortar and concrete was developed by applying the concept of wood-polymer composites to cement mortar and concrete in the late 1960s. Their research and development were actively conducted in the United States [12], the European countries [13-14] and Japan [15-16] from the late 1960s to the 1970s. 

Application of admixtures is as old as the history of mortars arrd concrete is. The ancient Romans used the animal blood, which was poprrlar also in Irrdia. According to Chandra [359], about 3,000 years BC the natmal admixtures of variorrs type were in use in India, for example molasses, fruit juices, bananas, olive oil, eggs, milk products and maity others. The natural admixtures to lime mortars in Irrdia can be classified, based on their specific role, as follows ... 

History of Second Mortar Baffallion (Salzburg, Austria, n.d.) p. 24. CMLHO. 

For an account of mortar battalion participation in the D-day screening, see above, Chapter Vm. (i) Rounds Away Two Years of Combat with Eighty-Third Chemical Mortar Battalion (Innsbruck, 1945), PP. 4t 4i- (a) History of Second Chemical Mortar Battalion, pp. 33-)4. 

The fighting in Italy had altered mortar commanders views as to the desirability of the -ton truck. Too much had been expected of these vehicles. The i%-ton trucks were still needed to haul ammunition from army supply points to the mortar battalion dumps and on to company dumps. Earlier thoughts on transportation had been conditioned by the experience of the fast-moving Sicilian campaign operations in Italy, characterized by slow movements and static situations, brought about the change. Opnl History of Cml Bns and the 4.2-inch Mortar in World War II, p. II, Italian Campaign, p. io . 

Unless otherwise noted, the unit material in this chapter has been taken from the histories, journals, and after action reports of the several mortar battalions. 

I) Brig. Gen. Hugh W. Rowan, "Mortars in Normandy, Chemical Warfare Bulletin (Jannary-February, I94t). (a) yad Bn History. 

Col. Ronald L. Martin, "9 ad Chemical Mortar Battalion History, Armed Forces Chemical Journal (October, IJJi). 

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