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Designing the longest fixed steel arch
388
CURRENT TOPICS.
[J. I;. I.
food industry authorities say the wet process of freezing is better than the quick, or dry, method, especially in the elimination of serious problems incident to dehydration and oxidation and in the ruggedness of the finished product in storage and transportation. Experience is said to have shown that an increase in weight due to Freezing the use of ice is more than offset by these advantages: is done in a “sharp” (low temperature) room or in brine tanks at 8” to IO" F. and because of this the process may be accomplished in any commercial ice plant where brine tank capacity is available. Processing incIudes preparation, grading, and blanching to inactivate the enzymes. The blanching fixes and heightens the color. Many different vegetables are so frozen and experiments are under way with freshly killed chickens. R. H. 0.
Large Quantities of Minerals Pass Through Bromine Plant.(Oil and Gus A., Vol. 35, No. 12.) During the two and one-half years of the operation of the bromine plant of the Ethyl-Dow Chemical Co. at Kure Beach, near Wilmington, N. C., one square mile of sea water, 172 feet deep, has been pumped in the process of producing bromine, of which the ocean harbors an inexhaustible supply. Present in this quantity of sea water were materials with a total tonnage of 5,699,335. Bromine recovered commercially totaled over IOJIOO tons. Potential by-products not actually recovered from the sea water include sodium chloride, magnesium sulfate, calcium chloride, potassium chloride, magnesium, aluminum, strontium carbonate, iron, copper, iodine, silver, and gold. Besides these main constituents, practically every element and compound is dissolved in the ocean water to a greater or lesser extent. In extracting bromide from sea water, now an established industrial operation, chemical science has accomplished the initial conquest of nature’s greatest reservoir of minerals. R. H. 0.
Designing the Longest Fixed Steel Arch.-D B. STEINMANAND C. H. GRONQUIST. (Engineerirtg News Record, Vol. 117, No. 7.) The main 8oo-ft. span of the Henry Hudson Bridge at present under construction over the mouth of the Harlem River, New York City, is the longest span fixed arch as well as the longest span plate girder arch built to date. It consists of two double girder arch ribs of silicon steel IZ~~Z ft. deep and 50 ft. apart with a rise of 120 ft. which support a superstructure composed of spandrel
Sept., 1936.1
CURRENT TOPICS.
389
columns, continuous fascia girders, and a deck on a maximum grade of 2% per cent. Steel towers, architecturally a dominant feature at either end of the arch span, are flanked by two 3oo-ft. continuous steel girder viaducts of 6o-ft. spans, and concrete frame and wail approaches. The total length of steel is 1530 ft. and of the entire structure is 2000 ft. The structure’s single deck will have a 42-ft. roadway and a q-ft. sidewalk at an elevation of 160 ft. above high water. Comparative designs of two-hinged and hingeless arch types showed little, if any, difference in economy between them. The two-hinged arch, however, required the heaviest sections at the quarter point whereas the arch designed for fixed-end conditions provided ribs with a constant minimum section for three fourths of their length with a gradual increase in section toward the skewback for a distance of IOO ft. Because of greater stiffness of the fixed arch under live load and for other distinctly advantageous reasons, the fixed arch type was chosen. R. H. 0. German Road Installs Unique Train.--(&i/way Age, Vol. IOI, No. 7.) The Luebeck-Buechere Railway has developed a two-unit Not only does the articulated coach for use out of Hamburg. coach present an interesting solution of the problem of reducing weight per passenger seat, but it also includes provisions for remote control of the streamline steam locomotive with which each coach is hauled so that the train does not require turning at the terminals. In one direction the coach is pulled by the locomotive and in the other is pushed by the locomotive at the rear end of the train. The first of these coaches was placed in service with a 2-4-2 type tank locomotive early in April. The coach has a total seating One unit is given over completely capacity of 300 in two decks. to third class with a small baggage compartment. There are seats The other unit is divided in the two decks for 156 passengers. between second and third class for which there are 144 seats. The car is 151 ft. 4% in. long over the buffers with the spacing between the truck centers 64 ft. 8% in. It weighs r56,527 lb. and combined weight of locomotive and coach is 310,657 lb. Air conditioning is provided throughout the car and the windows are fitted with fixed sash. The electric remote control includes an electric motor and chain drive for the movement of the steam controls on the locomotive. This is arranged so that the control includes a ‘ ‘deadman ” device, the compressed air cylinder for closing the throttle being operated simultaneously with the operation of the breaks when the deadman control functions. A loud speaker and bell device pro-
CURRENT TOPICS.
[J. I;. I.
food industry authorities say the wet process of freezing is better than the quick, or dry, method, especially in the elimination of serious problems incident to dehydration and oxidation and in the ruggedness of the finished product in storage and transportation. Experience is said to have shown that an increase in weight due to Freezing the use of ice is more than offset by these advantages: is done in a “sharp” (low temperature) room or in brine tanks at 8” to IO" F. and because of this the process may be accomplished in any commercial ice plant where brine tank capacity is available. Processing incIudes preparation, grading, and blanching to inactivate the enzymes. The blanching fixes and heightens the color. Many different vegetables are so frozen and experiments are under way with freshly killed chickens. R. H. 0.
Large Quantities of Minerals Pass Through Bromine Plant.(Oil and Gus A., Vol. 35, No. 12.) During the two and one-half years of the operation of the bromine plant of the Ethyl-Dow Chemical Co. at Kure Beach, near Wilmington, N. C., one square mile of sea water, 172 feet deep, has been pumped in the process of producing bromine, of which the ocean harbors an inexhaustible supply. Present in this quantity of sea water were materials with a total tonnage of 5,699,335. Bromine recovered commercially totaled over IOJIOO tons. Potential by-products not actually recovered from the sea water include sodium chloride, magnesium sulfate, calcium chloride, potassium chloride, magnesium, aluminum, strontium carbonate, iron, copper, iodine, silver, and gold. Besides these main constituents, practically every element and compound is dissolved in the ocean water to a greater or lesser extent. In extracting bromide from sea water, now an established industrial operation, chemical science has accomplished the initial conquest of nature’s greatest reservoir of minerals. R. H. 0.
Designing the Longest Fixed Steel Arch.-D B. STEINMANAND C. H. GRONQUIST. (Engineerirtg News Record, Vol. 117, No. 7.) The main 8oo-ft. span of the Henry Hudson Bridge at present under construction over the mouth of the Harlem River, New York City, is the longest span fixed arch as well as the longest span plate girder arch built to date. It consists of two double girder arch ribs of silicon steel IZ~~Z ft. deep and 50 ft. apart with a rise of 120 ft. which support a superstructure composed of spandrel
Sept., 1936.1
CURRENT TOPICS.
389
columns, continuous fascia girders, and a deck on a maximum grade of 2% per cent. Steel towers, architecturally a dominant feature at either end of the arch span, are flanked by two 3oo-ft. continuous steel girder viaducts of 6o-ft. spans, and concrete frame and wail approaches. The total length of steel is 1530 ft. and of the entire structure is 2000 ft. The structure’s single deck will have a 42-ft. roadway and a q-ft. sidewalk at an elevation of 160 ft. above high water. Comparative designs of two-hinged and hingeless arch types showed little, if any, difference in economy between them. The two-hinged arch, however, required the heaviest sections at the quarter point whereas the arch designed for fixed-end conditions provided ribs with a constant minimum section for three fourths of their length with a gradual increase in section toward the skewback for a distance of IOO ft. Because of greater stiffness of the fixed arch under live load and for other distinctly advantageous reasons, the fixed arch type was chosen. R. H. 0. German Road Installs Unique Train.--(&i/way Age, Vol. IOI, No. 7.) The Luebeck-Buechere Railway has developed a two-unit Not only does the articulated coach for use out of Hamburg. coach present an interesting solution of the problem of reducing weight per passenger seat, but it also includes provisions for remote control of the streamline steam locomotive with which each coach is hauled so that the train does not require turning at the terminals. In one direction the coach is pulled by the locomotive and in the other is pushed by the locomotive at the rear end of the train. The first of these coaches was placed in service with a 2-4-2 type tank locomotive early in April. The coach has a total seating One unit is given over completely capacity of 300 in two decks. to third class with a small baggage compartment. There are seats The other unit is divided in the two decks for 156 passengers. between second and third class for which there are 144 seats. The car is 151 ft. 4% in. long over the buffers with the spacing between the truck centers 64 ft. 8% in. It weighs r56,527 lb. and combined weight of locomotive and coach is 310,657 lb. Air conditioning is provided throughout the car and the windows are fitted with fixed sash. The electric remote control includes an electric motor and chain drive for the movement of the steam controls on the locomotive. This is arranged so that the control includes a ‘ ‘deadman ” device, the compressed air cylinder for closing the throttle being operated simultaneously with the operation of the breaks when the deadman control functions. A loud speaker and bell device pro-