Masonry Magazine December 1995 Page. 19
Mixing is carried out most effectively when the mixer is charged to its design capacity. Overloading can impair mixing efficiency and mortar uniformity. The mixer drum should be completely empty before charging the next batch. Mortar boxes, mortar pans, and mortar boards should be dampened prior to filling with freshly mixed mortar. Since the hydration of cement is initiated when cement and water are combined, mortar should be immediately transported from the mixing area to mortar pans or boards where work is progressing.
Summary
The importance of workmanship to the performance of masonry has been documented in numerous field evaluations, surveys, and research reports. The structural performance, resistance to water penetration, and durability of masonry are all affected by the level of workmanship. While workmanship is sometimes considered as only pertaining to the hands-on activities of the mason, adequate support, planning, and preparation are required to impart quality to masonry construction. Thus, it is appropriate to consider these topics as an integral part of good workmanship. Part 2 of this series on workmanship describes the hands-on mason skills that are required to construct quality masonry.
Related Publications
Readers of this publication may also be interested in the following publications available for purchase from the Portland Cement Association. A complete listing of PCA publications is given in the free PCA Catalog (MS254G). To order, write or call Order Processing, Portland Cement Association, 5420 Old Orchard Road, Skokie, Illinois 60077-1083, phone 708/966-6200.
Concrete Masonry Handbook, EB008M
Building Weather-Resistant Masonry Walls, IS220M
Mortars for Masonry Walls, IS040M
Masonry Cement Mortars, IS181M
Trowel Tips: Efflorescence, IS239M
Trowel Tips: Tuckpointing, IS240M
Trowel Tips: Mortar Sand, IS241M
Trowel Tips: Field Testing Mortar, IS242M
Trowel Tips: Hot-Weather Masonry Construction, IS243M
Trowel Tips: Cleaning Masonry, IS244M
Recommended Practices for Laying Concrete Block, PA043M
Recommended Practices & Guide Specifications for Cold Weather Masonry Construction, LT107M
CAUTION: Contact with wet (unhardened) concrete, mortar, cement, or cement mixtures can cause SKIN IRRITATION, SEVERE CHEMICAL BURNS, or SERIOUS EYE DAMAGE. Wear waterproof gloves, a long-sleeved shirt, full-length trousers, and proper eye protection when working with these materials. If you have to stand in wet concrete, use waterproof boots that are high enough to keep concrete from flowing into them. Wash wet concrete, mortar, cement, or cement mixtures from your skin immediately after contact. Indirect contact through clothing can be as serious as direct contact, so promptly rinse out wet concrete, mortar, cement, or cement mixtures from clothing. Seek immediate medical attention if you have persistent or severe discomfort.
This publication is intended SOLELY for use by PROFESSIONAL PERSONNEL who are competent to evaluate the significance and limitations of the information provided herein, and who will accept total responsibility for the application of this information. The Portland Cement Association DISCLAIMS any and all RESPONSIBILITY and LIABILITY for the accuracy of and the application of the information contained in this publication to the full extent permitted by law.
Portland Cement Association 5420 Old Orchard Road, Skokie, Illinois 60077-1083
pca
An organization of cement manufacturers to improve and extend the uses of portland cement and concrete through market development, engineering, research, education, and public affairs work.