Characteristics of mortars

The architect must also strike a balance between the short term requirements of the builder, who needs to be able to lay the masonry as quickly and economically as possible, with his own and the owner s long-term requirements for a durable, attractive and trouble-free construction. Table 26.4 summarises the results of a survey made in 1990 in the USA in which architects and builders were asked to prioritise the characteristics of mortars [26.23]. 

Skenderovic, B. (1992) Effect of addition of different quantities of polymeric dispersions on hydration of Portland cement and characteristics of mortars, in Proceedings 9th ICCC, New Delhi, Vol. 5, pp. 525-530. 

S. Naohiro, The strength characteristics of mortar containing glass powder. The 49th Cement Technology Symposium. JCA, Tokyo, (1995) 114-119. 

Table 2. Water Reduction and Setting Characteristics of Mortar Containing Lignosulfonates...

Choi, Y. W., Moon, D. J., Kim, Y. J., and Lachemi, M. Characteristics of mortar and concrete containing fine aggregate manufactured from recycled waste polyethylene terephthalate bottles. Construction and Building Materials, 23,2829-2835 (2009). 

The PLS calibration set was built mixing in an agate mortar different amounts of Mancozeb standard with kaolin, a coadjuvant usually formulated in agrochemicals. Cluster analysis was employed for sample classification and to select the adequate PLS model acording with the characteristics of the sample matrix and the presence of other components. 

M. Drdacky, Z. Slfzkova, Mechanical characteristics of historic mortars from tests on small sample non standard specimens. In Proceedings of 3rd Baltic Conference of Silicate Materials, Latvia, pp. 9 11,2007. 

H. Kast (104-07) Determination of Sensitivity to Friction (Medicion de la sensibili-dad al rozamiento) (107) Determination of Sensitivity to Initiation by Detonation (110-12) Determination of Sensitivity to Initiation by Influence (112-13) Determination of Power of Explosives using Trauzl Test (113-17), Small Lead Block Test (117), Quinan Apparatus (118), Guttmann Apparatus (118-19), Ballistic Pendulum (119-20), Mortar (Mortero probeta) (120-21) Determination of Efficiency of Initiating Devices by Lead Plate Test (121-23), Nail Test (123), Sand Test (124) and Acoustic Tests (124) Determination of Characteristics of Flames Produced on Explosion (125-29)... 

One outstanding characteristic of Japanese armament was the large variety of type and sizes of Mortars (Kyuho) in use. They were used not only as Infantry (Hohei) support weapons but also as Artillery Pieces (Ho). They ranged in size from the 50-mm Grenade Discharger (Tekidanto) to the 320-mm Spigot Mortar ( Spigot Kyuho)... 

Unlike the relation between brisance and PCJ, expl strength is not readily related to some detonation characteristic of the explosive. Attempts to relate strength to detonation energy are not wholly successful. Relative strength, based on ballistic mortar tests, correlates rather well with computed nRT, where n T are the computed moles of gas and detonation temp of the explosive, and R is the gas constant. Although n T can differ appreciably with the equation of state used in the computation, it appears that ratios of nRT (at least for similar explosives) do not suffer from this drawback... 

An especially convenient aspect of IR spectroscopy is its practice. A small amount of sample can be pressed between two NaCl or KBr (Table 6.19) disks and the spectrum can be determined without further preparation. A spectrum so obtained is recorded as neat or between salts. If the sample is a solid, it may be mixed in a mortar and pestle with KBr and then pressed into a disk. The salt disk may be placed directly in the IR beam. In neither case is there a concern about solvent peaks. Of course, solvents may be used. Carbon tetrachloride and chloroform are the most commonly used solvents when the compound requires dissolution. Alternately, the sample may be intimately mixed (mulled) with mineral oil (a hydrocarbon oil). The thick slurry may then be smeared on a salt disk and placed in the spectrometer. The brand of mineral oil used historically is Nujol and such slurries are still called Nujol mulls. The transmission characteristics of potential solvents for IR spectroscopy may be found in Table 6.20. 

In order to simulate the performance of the bomb when dropped firom aircraft, a mortar was constructed at Standard Oil Development Company and used to fire the bombs downward onto a target at any chosen velocity. The mortar was mounted on a movable crane. .. so that the point of impact of the bomb on the structure below could be closely controlled. Various sections of typical enemy domestic and industrial structures were employed to test the penetration, functioning, and fire-raising characteristics of the 6-pound oil bomb.. . Over 20,000 bombs were tested by Standard Oil Development Company before the final design was standardized. [Noyes, page 391]. 

DE.SCRIPTION AND CHARACTERISTICS. Description and characteristics of the principal classes of 60-mm mortar ammunition are ... 

Physical characteristics of the ideal mortar are as follows smaller elastic modulus, smaller unitary mass density, smaller thermal expansivity, smaller thermal conductivity and larger specific heat. 

Ohkubo, M. and Urakawa, Y. (1993), Test of mortar or concrete mixed with waste incinerated ash on the compressive strength and other characteristics, Journal of Struct. Constr. Engng, ALT, No. 443, Jan., pp. 1-9... 

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