Hydraulic concret

Ravina, D. and Shalon, R. (1961). Proceedings PJLEM/CEMBUREAUColloquium on Shrinkage of Hydraulic Concretes, Madrid, Vol. II, Edigrafis, Madrid, 46-51. 

A trial batch of concrete was performed, thereby producing the satisfactory mixture proportions recommended using in the construction of the left guide-wall dam section. The concrete thermal properties were tested according to the standard methods of the Chinese Test Code for Hydraulic Concrete (1982). Table 1 gives the test results. 

Outlet Ducts 316L,317LMN, FRP, Plastic Lined CS Hydraulic Concrete,... 

From Moody, Trans. Am. Soc. Mech. Eng., 66, 671-684 (1944) Mech. Eng., 69, 1005-1006 (1947). Additional values of e for various types or conditions of concrete wrought-iron, welded steel, riveted steel, and corrugated-metal pipes are given in Brater and King, Handbook of Hydraulics, 6th ed., McGraw-Hill, New York, 1976, pp. 6-12-6-13. To convert millimeters to feet, multiply hy 3.281 X l0- ... 

Zement-kalk, m. hydraulic lime, -kalkmdrtel, m. lime-and-oement mortar, -kalkstein, m. hydraulic limestone, -kohle, /. cementation carbon, -kufe, -kiipe, /. cement (or concrete) vat. -kupfer, m. cement copper, -mastiz, m. mastic cement, -metoll, n. metal precipitated by the cementation process. -miUk, /. thin cetnent mortar. 

Environments are either gases or liquids, and inhibition of the former is discussed in Section 17.1. In some situations it would appear that corrosion is due to the presence of a solid phase, e.g. when a metal is in contact with concrete, coal slurries, etc. but in fact the corrosive agent is the liquid phase that is always present. Inhibition of liquid systems is largely concerned with water and aqueous solutions, but this is not always so since inhibitors may be added to other liquids to prevent or reduce their corrosive effects — although even in these situations corrosion is often due to the presence of small quantities of an aggressive aqueous phase, e.g. in lubricating oils and hydraulic fluids (see Section 2.11). 

Concretes are cements containing a large proportion of gravel. Hydraulic cements are cements that set (harden) in wet environments, as required when building structures submerged in water. Like all other cements used in ancient times, hydraulic cements were also composite materials in which one particular component, such as pozzolana in ancient Rome (see text below), endowed the cement with the property of setting in wet environments (Gani 1997 Akroyd 1962). 

Cementitious materials use a hydraulically setting cement such as Portland cement as a binder with a filler material of good insulation properties, e.g., verminculite, perlite, etc. Concrete us frequently used for fireproofing because it is easily installed, readily available, is quite durable and generally economical compared to other methods. It is heavy compared to other materials and requires more steel to support that other methods. 

Figures 10.9S(a,b) show isopleths calculated between (a) corium and siliceous concrete and (b) corium and limestone concrete. Comparison between experimental (Roche et al. 1993) and calculated values for the solidus are in reasonable agreement, but two of the calculated liquidus values are substantially different. However, as the solidus temperature is more critical in the process, the calculations can clearly provide quite good-quality data for use in subsequent process simulations. Solidus values are critical factors in controlling the extent of crust formation between the melt-concrete and melt-atmosphere interface, which can lead to thermal insulation and so produce higher melt temperatures. Also the solidus, and proportions of liquid and solid as a function of temperature, are important input parameters into other software codes which model thermal hydraulic progression and viscosity of the melt (Cole et al. 1984).

The permeability of concrete is a guide to its durability (Section 1.5.2) but it can also be relevant to the design of structures which are intended to withstand a hydraulic head of water or other liquid. Extreme porosity is usually... 

Calcium sulfamate and magnesium sulfamate are used effectively as a stiffening promoter of concrete and hydraulic cement (see Cement). 

At an eastern refinery, an aerated lagoon provides the primary treatment for the refinery wastes. The lagoon effluent typically contains 20 to 40 ppm oil, 20 to 40 ppm suspended solids, and associated BOD. The system flow is 1,400 gal/min. The effluent from the aerated lagoon is treated with 10 to 30 ppm of aluminum sulfate that is mixed in a hydraulic flash mix chamber and then applied to an open concrete mixed-media filter. The single mixed-media filter is rated at 5 gal/min/sq ft. Typical removal efficiencies reported are as follows. 

Mixed media has also been used to convert existing filters. A considerable number of rapid sand filters, either in pressure or concrete containers, have been expanded in capacity through conversion to mixed media. Generally, certain hydraulic revisions are also required, particularly to the influent and effluent piping system. However, it is not unusual to more than double the capacity of an existing plant by the installation of mixed-media materials with the appropriate hydraulic changes. Each system must be looked at individually, however, to assure that the conversion is economic. 

In recent years use of the oxide as a constituent of cement has been advocated,1 especially in Sweden. Thus, a mixture of Portland cement (60 to 70 per cent.) and white arsenic (40 to 30 per cent.) heated to 200° to 250° C. affords a hydraulic cement of normal setting time and of less solubility than ordinary cement, so that lime liberation is inhibited and the resistance to water improved. Wooden structures exposed to the action of sea water may be protected by spraying with a concrete composed of white arsenic, cement and sand in the proportions 1 3 12. The arsenic makes the mixture elastic and helps the cement to adhere to the wood. There is, however, danger in the too widespread application of arsenic in the directions described above. 

Cement and Concrete in Ordnance. The term cement, which includes a great variety of materials, refers here only to the hydraulic material(mainly Portland cement) and the term concrete refers to mixts of cement with sand, gravel, broken stones, etc. and sufficient w to cause the cement to set. If steel rods are used... 

In the melted state elementary sulfur is an excellent binder for aggregates such as sand, gravel, crushed stone, and similar materials. When a hot sulfur aggregate mixture is left to set, a material of concretelike hardness is obtained. This property leads to the term sulfur concrete or sulfur mortar, which is wrong strictly speaking, since the word concrete is used to refer to a product in which aggregates are bound with hydraulic products such as cement or with limestone. However, since polymer-bound aggregates recently developed to industrial maturity have been called polymer or synthetic resin concrete, the term sulfur concrete is maintained in this chapter. 

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