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Engineering progress in 1932. Road construction
Apr., 1933.1
CURREST
TOPICS.
507
resulted in a product with less tricalcium silicate and more dicalcium silicate than standard portland and a minimum of tricalcium aluminate. As a guide to design procedure for the suspension spans of the Bay Bridge at San Francisco, steel models nearly IOO ft. long were used. A special musical tensometer proved useful in determining variation of suspender pulls. In Cleveland statically indeterminate stresses in a novel steel parabolic arch of high rise having lateral bracing only in a relatively short length near the crown were determined by direct measurement on a celluloid model. Weld structure is receiving more scientific attention than ever before. Some pioneer tests of corrosion fatigue of weld metal were made at Lehigh University. The rigidity of welded beam-to-column connections was the subject of research at the University of Toronto. At Purdue University stress distribution in welded buttstrap joints was the subject of an extensive investigation. Engineering Progress in 1932. Water Power Changes.-(Eng. News-Record, IIO, 35.) Additions to the available water power were made through completion of the initial installations in such plants as that at Rock Island on the Columbia River, Safe Harbor on the Susquehanna, Beauharnois on the St. Lawrence and Chats Falls on the Ottawa. The 84,ooo-hp. turbines for Dnieprastroy, Russia were the largest built when they were installed but will soon be exceeded by the turbines at Hoover Dam at least five of which will have I 15,ooo-hp. capacity each. The past year saw an increase in the head used on Kaplan (automatically adjustable blade propeller) turbines, one designed to operate under a head of 106 ft. having been ordered for the Shannon plant in Ireland. Engineering Progress in 1932. Transportation Problems.(Eng. News-Record, IIO, 35.) Important innovations on the technical side of railroad development were: an entirely new type of passenger car for branch-line service; an experimental car for suburban service having the passenger capacity greatly increased by seats placed at two levels; further extension of aluminum to the construction of freight-car bodies to save weight; and the further application of air-conditioning to passenger-train service. The new cars for branch-line service have wheels equipped with pneumatic tires and bodies fabricated of thin formed plates of stainless steel. Engineering Progress in 1932. Road Construction.-(Eng. News-Record, IIO, 35.) Continuous improvement of road structure
CURRENT
[J. F. I.
TOPICS.
and road building processes characterized the highway construction of the past year as it has for a dozen years past. A revival of the old Hassom cement-penetration macadam construction and experimentation with an analogous cement-bound stone construction, using a new bitumized cement, constitute the nearest approach to new road types. For both bituminous and brick-surfaced roads a decided improvement was shown in concrete-base design to reduce cracking. Paving-brick manufacturers have introduced a de-aired brick, having greater strength and density. Bituminous materials increased their usefulness in the lower-cost road field by virtue of better control of materials, more careful construction procedure and increased mechanization. Single-Vane Wind Turbine.-(Power, 77, 62.) Low-cost electrical energy for advertising signs and similar low loads at points of sustained air circulation is possible by this wind turbine, using a stainless steel hollow air-foil vane fabricated by the shot-welding process. One particular model is a I-Kw unit with the generator mounted on the mill shaft and operating through a 9-1 step-up gear. The speed is practically constant at 120 r.p.m. for all wind velocities above 15 m.p.h. attained by the automatic feathering of the single balanced vane.
THE
FRANKLIN
INSTITUTE
OFFICERS FOR 1933 NATHAN
Prcsidcnt
HAYWARD HENRYHOWSON C. C. TUTWILER
Vice-firesidests
Scn,L?tory h.m.;;Secrctory
Astista~t Trsosurer Catroller
end Librarian
WALTON FORSTALL W.CNKiTINW~THERILL HOW~RDMCCLEN~AAN ALFRED RIGLING BENJAMINFRANKLIN MARSHALLSMORGAN WILLIAMF.JACKSON.J~.
Board of Managers H~RYBUTLERALLEN GEORGEH.BBNZON.JR. EDWARDG.BUDD ~~&;R~B~~s TkohmF. CLARK WALTONCLARK CYRUSH.K.CURTIS
C-~H.EWING SAWELS.FBLS ~TX"RW.GOODSPEED CLA~NC~A.HALL GBORGEA.HOADLEY A.AT~ATERKBNT L.H.KINNARD ELISHALEE
ROs~RTW.L~SLW HORACE P.LlVERslDGB MALCOLMLLOYD.JR. C-ISPBNROSE GEORGEWHARTONPEPPER Jm.msS.Rocrms GSORGED.ROSBNGARTEN HASELTINESMITH
CURREST
TOPICS.
507
resulted in a product with less tricalcium silicate and more dicalcium silicate than standard portland and a minimum of tricalcium aluminate. As a guide to design procedure for the suspension spans of the Bay Bridge at San Francisco, steel models nearly IOO ft. long were used. A special musical tensometer proved useful in determining variation of suspender pulls. In Cleveland statically indeterminate stresses in a novel steel parabolic arch of high rise having lateral bracing only in a relatively short length near the crown were determined by direct measurement on a celluloid model. Weld structure is receiving more scientific attention than ever before. Some pioneer tests of corrosion fatigue of weld metal were made at Lehigh University. The rigidity of welded beam-to-column connections was the subject of research at the University of Toronto. At Purdue University stress distribution in welded buttstrap joints was the subject of an extensive investigation. Engineering Progress in 1932. Water Power Changes.-(Eng. News-Record, IIO, 35.) Additions to the available water power were made through completion of the initial installations in such plants as that at Rock Island on the Columbia River, Safe Harbor on the Susquehanna, Beauharnois on the St. Lawrence and Chats Falls on the Ottawa. The 84,ooo-hp. turbines for Dnieprastroy, Russia were the largest built when they were installed but will soon be exceeded by the turbines at Hoover Dam at least five of which will have I 15,ooo-hp. capacity each. The past year saw an increase in the head used on Kaplan (automatically adjustable blade propeller) turbines, one designed to operate under a head of 106 ft. having been ordered for the Shannon plant in Ireland. Engineering Progress in 1932. Transportation Problems.(Eng. News-Record, IIO, 35.) Important innovations on the technical side of railroad development were: an entirely new type of passenger car for branch-line service; an experimental car for suburban service having the passenger capacity greatly increased by seats placed at two levels; further extension of aluminum to the construction of freight-car bodies to save weight; and the further application of air-conditioning to passenger-train service. The new cars for branch-line service have wheels equipped with pneumatic tires and bodies fabricated of thin formed plates of stainless steel. Engineering Progress in 1932. Road Construction.-(Eng. News-Record, IIO, 35.) Continuous improvement of road structure
CURRENT
[J. F. I.
TOPICS.
and road building processes characterized the highway construction of the past year as it has for a dozen years past. A revival of the old Hassom cement-penetration macadam construction and experimentation with an analogous cement-bound stone construction, using a new bitumized cement, constitute the nearest approach to new road types. For both bituminous and brick-surfaced roads a decided improvement was shown in concrete-base design to reduce cracking. Paving-brick manufacturers have introduced a de-aired brick, having greater strength and density. Bituminous materials increased their usefulness in the lower-cost road field by virtue of better control of materials, more careful construction procedure and increased mechanization. Single-Vane Wind Turbine.-(Power, 77, 62.) Low-cost electrical energy for advertising signs and similar low loads at points of sustained air circulation is possible by this wind turbine, using a stainless steel hollow air-foil vane fabricated by the shot-welding process. One particular model is a I-Kw unit with the generator mounted on the mill shaft and operating through a 9-1 step-up gear. The speed is practically constant at 120 r.p.m. for all wind velocities above 15 m.p.h. attained by the automatic feathering of the single balanced vane.
THE
FRANKLIN
INSTITUTE
OFFICERS FOR 1933 NATHAN
Prcsidcnt
HAYWARD HENRYHOWSON C. C. TUTWILER
Vice-firesidests
Scn,L?tory h.m.;;Secrctory
Astista~t Trsosurer Catroller
end Librarian
WALTON FORSTALL W.CNKiTINW~THERILL HOW~RDMCCLEN~AAN ALFRED RIGLING BENJAMINFRANKLIN MARSHALLSMORGAN WILLIAMF.JACKSON.J~.
Board of Managers H~RYBUTLERALLEN GEORGEH.BBNZON.JR. EDWARDG.BUDD ~~&;R~B~~s TkohmF. CLARK WALTONCLARK CYRUSH.K.CURTIS
C-~H.EWING SAWELS.FBLS ~TX"RW.GOODSPEED CLA~NC~A.HALL GBORGEA.HOADLEY A.AT~ATERKBNT L.H.KINNARD ELISHALEE
ROs~RTW.L~SLW HORACE P.LlVERslDGB MALCOLMLLOYD.JR. C-ISPBNROSE GEORGEWHARTONPEPPER Jm.msS.Rocrms GSORGED.ROSBNGARTEN HASELTINESMITH