Silica-Based Mortar

There are two different bonding systems employed with the block a urethane asphalt adhesive/membrane or a special inorganic silica-based mortar. The choice depends on mechanical considerations and on the chemical and thermal environment. 

Inorganic Silica-Based Mortar The completely compatible mortar is a two-component silica-based mortar used to bed and bond the block when the thermal and chemical environments exceed the capabilities of the adhesive/mem-brane and where vibration and thermal shock are not serious factors. Its thermal characteristics and chemical resistance are identical to that of the block. The cured joints are rigid, dense and abrasion resistant. (See Chapter 22.)... 

Foamed glass block laid in its silica-based mortar over a suitable membrane is a good choice for lining these areas. During shutdowns, it is resistant to the wide range of acid that may condense on the surfaces of the ductwork. When the incinerator is operating, the block can withstand the high gas temperatures... 

Peimchem Mortar. [AtochemN.Am.] Two-component, silica-filled chmnical-resistant vinyl ester resin-based mortar mortar for construction in pulp/pa-per, chemical process, food and b er-age plant industries. 

Abdelrazig, Sharp El-Jazairi (1988, 1989) prepared a series of mortars based on a powder blend of MgO and ADP with a quartz sand filler. They were hydrated by mixing with water. A mortar I (MgO ADP silica water = 17T 12-9 70-0 12-5), with a water/solid ratio of 1 8, formed a workable paste which set in 7 minutes with evolution of ammonia. The main hydration product, struvite, was formed in appreciable amounts within 5 minutes and continued to increase. Schertelite also appeared, but only in minor amounts, within the first 5 minutes and persisted only during the first hour of the reaction. Dittmarite appeared in minor amounts after 15 minutes, and persisted. 

C-579 Compressive strength of chemical-resistant mortars, grouts, monolithic surfacing and polymer concrete (based on resin, silicate, silica and sulphur binders). 

The normal lining construction consists of a membrane on the steel shell and one layer of acid brick in a resin mortar. The membrane materials used have been a silica filled latex rubber or, more recently, a silica filled urethane. Either of these membranes is installed by troweling it onto the steel shell. The mortars used have been polyester or vinyl ester based and are used in the back joints, bed joints, and side joints. That is, the brick are completely surrounded by the mortar, except, of course, for the face. The equipment in which this type of construction is used includes the chlorine dioxide storage tank, the chlorine dioxide generator spent acid tank, and the chlorine dioxide bleach tower. 

Caicium hydroxide Epoxy resin Sulfur mortar base Silica, fumed... 

Toledo Filho et al. [32] studied the effect of a series of treatments on natural fiber and cement matrix in order to increase durability of cement mortars reinforced with sisal fibers. Based on results from their investigation, it was concluded that incorporation of sisal fibers significantly reduced mechanical properties of composite material. However, the mechanical properties of composite were maintained over time if the sisal fibers were immersed in a suspension of silica fume. This is because the silica fume particles contact the fiber and their size allows them to be located in smaller defects in the fiber, preventing that compounds such as calcium hydroxide, come into contact with the fiber and destroy it by growth of crystals. 

Chemically resistant mortars and grouts are based on organic and inorganic chemistry. They consist of a liquid resin or an inorganic binder fillers such as silica, carbon, or combinations of the same and a hardener or catalyst system that may be incorporated in the filler or added as a separate component. 

Pfeil et al. received a patent in 2003 on Mortar Composition, Curable by Frontal Polymerization, and a Method for Fastening Tie Bars. Chemical anchors are adhesives, usually based on epoxy chemistry that are used to secure rods in holes drilled in concrete. Their approach is to use multifunctional acrylates with silica and quartz fillers and thermal initiators as the frontally cured chemical anchor. 

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