Simple practical methods of calculating strains on girders, arches, and trusses; with a supplementary essay on economy in suspension bridges

E. W. (Edward William) Young

Sujets

• Bridges

Informations

• Publié par: les_archives_du_savoir
• Nombre de lectures: 8
• Langue: English
• Poids de l'ouvrage: 10 Mo

Extrait

H-l"
#
LIBRARY
OF THK
OF CALIFORNIA.UNIVERSITY
Received
^\fAccessions No:s$&^ No.ShelfPRACTICAL METHODSSIMPLE
OF CALCULATING
STEAINS ON GIRDEES, AECHES,
AND TEUSSES;
WITH A SUPPLEMENTARY ESSAT ON
SUSPENSION BRIDGES.ECONOMY IN
BY
E. W. YOUNG,
\
ASSOCIATE OP KINO'S COLLEGE, LONDON,
THE OP CIVIL ENGINEERS.AND MEMBER OP INSTITUTION
1
UNIVERSITY
ILonfcon :
AND CO.MACMILLAN
1873
[All Rights reserved.]\J
'V
PBIMTED BY C. J. CLAY. M.A.
PEESaAT TUB UNIVEESITYPREFACE.
THE bulk of the work was written severalfollowing years ago,
to a want which was then muchand was felt,designed supply
methods ofthat of a treatise strainsgiving simple calculating
on and other kindred structures.arches, roofs,trusses,girders,
at that time were either tooThe treatises orexisting meagre
too mathematical for the student. One classaverage engineering
him results without to him how were ob-gave explaining they
thetained the in bewildered
; other, making required explanation,
him with mathematical formulae hisbeyond comprehension.
works on thisSeveral excellent subject having appeared
last few the issue of another from thethe pressduring years,
I have becausebe otherwise,superfluous. judgedmight thought
in this little work arethe methods mostly original,adopted
than usual. A ofas I consider,and, simpler knowledge simple
aon the of where littledeflection,subjectequations, excepting
is is the extent of theelementary trigonometry required,
for out themathematical attainment problemsrequired working
in this work to the reader.
presented
"" fromarticle on inThe Economy Suspension Bridges" Engi-
the onis added as a tosupplement chapter Suspen-neering"
sion Bridges.
THE AUTHOR.CONTENTS.
PAOB
iiiPREFACE
CHAPTER I.
OF FORCES.OF LEVERS AND THE RESOLUTION
The Lever. Fulcrum. Arm or Moment. Levers of threeleverage.
of Forces. Resul-kinds. Bent Lever. Examples. Parallelogram
Corollaries. of Forces.tant. of Forces. PolygonTriangle
of the of Forces. Resolution orExamples Polygon Decomposition
Alternative the Lever or Parallel-of Forces. Example. methods,
ofof Forces. Lever method. Method of Parallelogramogram
Forces. Forces in differentacting planes
CHAPTER II.
FLANGES.GIRDERS WITH PARALLEL
Load at centre of Load strain at centre. Strainspan. evenly distributed,
at of loaded Girders.theany point Flange. Example. Irregularly
Strain on the web. force. Cantilevers. Load at the ex-Shearing
Distributed load. Wooden beams. Neutral axis. Thetremity.
web in Iron Girders. Strains on the web. ResultExamples.
checked method 14. Formula forby described, p. Example.
Force. First SecondShearing loading, case, Bays equal.Irregular
Thirdof an Loadcase, Bays size, symmetrical. case,unequal Bays
and Trusses and Lattice Girders. WithoutLoading irregular.
verticals. Warren Truss. Strains on . . . .12DiagonalsTl CONTENTS.
III..CHAPTER
HOGBACKED GlBDERS.
PAGF.
on the Strains on the with aStrains Flanges. Diagonals. Comparison
as struts. of bothGirder.Flanged Diagonals Diagonalsparallel
. . . . . . 41kinds used . . . . V .
CHAPTER IV.
THE BOWSTRING GIRDER.
Strains on the Curve of Method of theFlanges. Equilibrium. drawing
Curve of To draw the Curve ofEquilibrium. Regular Loading.
with a versine.Equilibrium given Irregular Loading, Bays equal.
of Resistance.LineIrregular Loading, Bays unequal. greatest
Methods of Distortion. First Method. Second Method.resisting
Third Method. Fourth Fifth Effect ofMethod. elasticity
in the Load the Load ondistributing among Diagonals. resting
the . . , , . .. . , . . 45:,.Top r
CHAPTER V.
THE ARCH.
Thrust at Crown. Curve of for anMethod of thefinding Equilibrium
ofArch of Other methods of Distortion theresistingMasonry.
on the Other forms ofArch. Strains filling.Spandrils. Spandril
of of Pier. Effect ofArched bridges multiple span. Stability
on Pier. of aHorizontal Girder. Transverse strain Stability
.61Arched ViaductWrought-iron
CHAPTER VI.
BRIDGES.SUSPENSION
at of theStrain at centre of Strain Chain. Strainany portionSpan.
on the Back-tie. Methods of ..... 72stiffening