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Cleaning “New Masonry” Workshop. Cleaning Committee. Diedrich Technologies Fabrikem PROSOCO Weathershield, Inc. St. Marys Cement. Thank You!. Introduction.
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Cleaning Committee • Diedrich Technologies • Fabrikem • PROSOCO • Weathershield, Inc. • St. Marys Cement Thank You!
Introduction • This workshop is a part of a Continuing Education Program for Masonry. The scope of the program is for participants to continue lifelong learning to enhance their success in manufacturing a satisfactory masonry system. • Certification will be issued upon successful completion of this workshop, “Cleaning ‘New Masonry’ Workshop,” by demonstrating competency through written examination. The information presented in this workshop focuses on the cleaning of new masonry walls.
Introduction • The information has been based on the Building Code Requirements for Masonry Structures (ACI 530-02/ASCE 5-02/TMS 402-02). Acknowledgements to Diedrich Technologies, Fabrikem, Prosoco for product information and literature; the Brick Industry Association, the Cast Stone Institute, the Environmental Protection Agency, the Indiana Limestone Institute, Michigan Occupational Safety and Health Administration (MIOSHA), the National Concrete Masonry Association, the Rocky Mountain Masonry Institute, and the Portland Cement Association.
Introduction • Decisions to utilize this information are not within the purview of the Masonry Institute of Michigan and are for applicator who are competent to accept the responsibility for applying the information. The Masonry Institute of Michigan is unable to assume responsibility for any errors and omissions resulting from the use of this information.
Agenda • Masonry Units • Mortar • Grout • Building Code Requirements • MIM and Masonry Associations CleaningRecommendations • Red Clay Brick • Light Colored Clay Brick • Architectural Concrete Block (smooth, split, ribbed) • Architectural Concrete Block (burnished) • Concrete Brick • Natural Stone (limestone) • Cast Stone • Calcium Silicate • References
High Pressure (Improper Cleaning) New photo
Vanadium Stain (green or yellow stains)(Improper Cleaning) These stains are usually from vanadium salts. They may be found on red, buff or white clay products; however, they are most objectionable and more readily apparent on the lighter-colored units. The chloride salts of vanadium require highly acidic leaching solutions, and are usually the result of washing brickwork with acid cleaning solutions.
Manganese Stain(Improper Cleaning) Under certain conditions, tan or brown, and sometimes gray staining may occur on the mortar joints of brickwork. Occasionally, the brown stain will streak down onto the faces of the brick. This type of stain is the result of the use of manganese dioxide as a coloring agent in the units.
Building Bloom(Stain) A source of moisture which may cause "new building bloom" and contribute to future occurrences of efflorescence in a building is the water which enters the assembly during construction. The improper protection of a building during construction may significantly contribute to future problems, including efflorescence.
Efflorescence(Stain) Efflorescence is a crystalline deposit of water-soluble salts on the surface of brick masonry. Although efflorescence is unsightly and a nuisance to remove, it is usually not harmful to the brick masonry. By definition efflorescence is water soluble and can be cleaned. Efflorescence is usually white in color; however, all white stains on brick masonry are not necessarily efflorescence.
Lime Run (Calcium Carbonate)(Stain) Carbonate deposits, if they occur, usually appear as a gray-white, crusty spot in the form of a vertical "run-down" shape on the face of the wall. …."lime run" is not directly a result of lime in the mortar. Carbonate deposits nearly always occur at a small hole or opening in the face of the masonry. These carbonate stains can be removed using a weak solution of hydrochloric acid, applied directly to the deposit. Care must be taken to properly wet the wall area first and rinse it thoroughly after cleaning. This is especially true when removing carbonate deposits from light-colored brick
Masonry Acid Burn(Muriatic Acid)(Improper Cleaning) Aggressive: creates uneven appearance erodes mortar, reduces weather resistance
Improper Cleaning Sure Clean 600
Mortar A mixture consisting of cementitious materials, fine aggregate, water, and with or without admixtures, that is used to construct unit masonry assemblies
Purpose Hold units together Accommodate unit tolerances
Purpose Provide water penetration resistance Hold units apart
Properties Plastic (Mason) Workability Flow Water Retentivity Stiffening Characteristics Board Life Hardened (Designer) Bond Extensibility/Plastic Flow Compressive Strength Durability
Workability Most important plastic property Supports weight of units Spreads easily Adheres to vertical surfaces
Bond Complete and intimate contact between mortar and unit is essential for good bond
Compressive Strength Relatively easy to measure – used as principal criterion
Types • A1 A2 B C D • MASONW ORK X
Mortar Materials cement aggregate water lime admixtures
Cement Portland cement masonry cement Portland cement air entraining additives water repellency agents mortar cement similar to masonry cement requires lower air content flexural bond strength requirement
Aggregate natural or manufactured acts as an inert filler provides economy workability reduced shrinkage influences compressive strength should be well graded harsh mortar weak mortar
Water contributes to workability hydration of cement carbonation of lime suction of units potable use the maximum amount of water needed for workability retempering
Lime contributes to workability water retentivity elasticity autogenous healing
Admixtures A wide variety of admixtures for masonry mortars is available to the masonry industry. In general, they are classified as: air entrainment water retentivity water repellency workability accelerated set color no chlorides Only used when specified
Mortar • Wall System • (Above Grade Walls) Suggested Type • Veneer N • Reinforced Masonry N or S • Unreinforced Masonry S
Masonry veneer non-structural Reinforced masonry design based on the cracked section (steel reinforcement resists tension only) Unreinforced masonry design based on the uncracked section (masonry resists tension only) Specify the weakest mortar that meets structural requirements.