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Concrete typical mixtures

The Hibernia offshore concrete platform on the Grand Banks off the coast of Newfoundland, Canada, is a 111 m structure and required about 165 000 m of superplaticized high-strength concrete. The typical mixture proportions and the properties of the concrete used for the skirt elements of the structure are shown in Table 7.18 [70]. The precast skirts are a series of reinforced concrete elements which were joined together to form continuous walls to support the base slab of the structure [69]. [Pg.462]

Silica fume when used in conjunction with superplasticizers plays an important role in improving the cohesion of the shotcrete mix, allowing for the build-up of the sprayed concrete on vertical surfaces, within a short period, without sloughing off. In addition the combination of these admixtures has provided ease of pumping, better compaction and greatly reduced the rebound, thus minimizing waste and cleaning time. Typical mixture proportions and properties for wet-mix superplasticized shotcrete are presented in references 69 and 72. [Pg.468]

Table 13.6 Typical mixture proportions and properties of Reactive Powder Concretes (RPC)... Table 13.6 Typical mixture proportions and properties of Reactive Powder Concretes (RPC)...
Dampproofers based on liquid fatty acids, such as oleic, caprylic and capric, are used as major components in fatty-acid mixtures. A typical example is shown in Table 4.2 [3]. The mixtures are added directly to the concrete mix without predilution, or addition to the gauging water. [Pg.232]

Another foreign body that typically interferes in eye bums is calcium oxide in any form like fluid concrete to fresh mixtures of CaO (Calcium oxide) with water. The reactive CaO dissolves with the water being attracted from the eye into Ca with additional hydroxyl ions. The saponification of the tissues by the alkali results in the diffusion of the foreign body into the tissue with deep comeal foreign body, difficult to remove [21]. All other known bioactive foreign bodies usually, more or less, follow these two different reaction types. [Pg.68]

Cold-weather concrete mixtures incorporating non-chloride antifreeze accelerating admixtures have been used in a number of projects. Two of these projects are profiled. All the concrete mixtures described below were treated with the sodium-thiocyanate-based CWA mentioned earlier. These projects illustrate the impact of this admixture on normal concrete mixtures containing Class C fly ash, since fly ash typically delays time of setting and, hence, would not be a logical choice for cold-weather concrete. [Pg.382]

The residue obtained is repeatedly washed with fresh amounts of the same solvent to maximize yield. Solvent is then recovered in a still at reduced pressure, which lowers the solvent s boiling point and permits the use of gentle heat. The concentrated extract is not distilled but is retained in the vessel in a liquid state. When it is removed and cooled, the concentrated extract solidifies to a waxy consistency called a concrete, which is made up of approximately 50% odourless wax. The unwanted wax is removed by washing with alcohol, which extracts the essential oil. The alcohol mixture is then filtered and alcohol is removed by vacuum distillation. The final residue is called the absolute. A typical solvent extraction plant is shown in Fig. 4.4 in this system the solvent is pumped through a bed of the plant material. [Pg.83]

Concrete is a cheap fire and corrosion resistant material. However, active species, especially easily soluble ions such as cesium, can be leached from it by water. Addition of plastic binders to the concrete in order to improve its properties have been suggested. In the continuous bitumen extruder process for semi-liquid wastes all water is directly eliminated, considerably reducing the waste volume. The bitumen mixture is placed in steel drums of standard size (150-2001). When additional shielding is desired, the filled drums are placed into disposable or reusable sleeves of concrete, iron, or lead. Such a sleeve of 12 cm lead weighs 7 t, and reduces the surface dose rate by a factor of —10. A typical unshielded bitum i drum may have a surface dose rate of 1 Sv h necessitating remote handling. [Pg.578]


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See also in sourсe #XX -- [ Pg.977 ]




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Concrete Mixtures

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