Download - Design of Concrete 00 Ry La

7/27/2019 Design of Concrete 00 Ry La

1/70


2/70


3/70

^T 310lylander, PaulDesign of a concreteelevator


4/70


5/70


6/70


7/70

DESIST OF A COITCHSTE ELEVATORA THESIS

presented "byPAUL EYLAITDER

to thePRESIDEITT AlID FACULTY

ofARMOUR ITTSTITUTE OF TECIHTOLOGY

for the degree ofBACHELOR OF SCISITCE OF CIIVIL EITGnTEERIITG

Having completed the prescribed course of study inCIYIL :-lTGIIT?^RI!IG

1913

Approved; J^ W^'k0^


8/70

siariHT Ay,d bîttozosiHHcrauTa jxjki

roaiOTfflTDZ? TO HTOTITglll fllIOfCL\

pîffarraie- okhios ô HOjanoAe

siiiHarJuoHH jivioSX9I

:l)7(nq(l'V

.naxrrsgml^'" " :> "-oeao^ci'L

, 8oiC>xfJ2 ^niieonigrtr: "io i^peflrA^. aoioi;;JG le-ii/iltrO Ito nsoCI

'-^ V ^- :" >o

YrOOJO(4H0?^V: !


9/70

-1-

PR0GKE3 DT GEAIK rLI:]VA?OR COITSTBgCTIOIT.In ancient days fjrain was piled upon the ground, where in dry countri

it was fcept in a good condition for long periods. The first step toward .proteing it from the weather and providing permanent places for its storage viob \m-doubtedly cade by making excavations in the groxind, covering the floor and sideivith stone and placing a roof of poles and thatch overhead. As iran became morecivilized, graineries or bins above ^'round v;here built either of stcne or wood,but these constructions- were generally in the form of sinfjle bins, devoid'ofir.cchsnical appliances for filling and emptying, except in -rare instances, as \vthe esse with the Egyptians, of small crpacity.

It was not until comparatively late years that, the "cribbed" woodielevator, having a large liuwber of eicall con^artments, made its apijeorance. Thstructures vrere a vast improvement on all preceding ones, but. they in turn haveb>?on displrced, and within the past ten years constriiction of grain elevatorshas evolved fron stereotyped lines of simple crude woodworking to scientificdesigning of structures for special purposes and in more permanent materials.

The early builders of wooden elevators were resolute men of indortitaenergy, but woefully lacking in scientific knowledge, who,- without waiting forplans, could from the merest outline throw fe> by ira in- strength a structure havia cax>acity of two or more million bushels in as phort a space of time as thurtydays, \7ood was cheap and easily handled, and a few hundred feet of board moreless made no appreciable difference in cost. iBistakes could be corrected afterward. If, for instance, the walls were lacking in strength and tulged from ex-


10/70


11/70


12/70


13/70

-s

a radical snd comprehensive nature. There have been so many other advances aloscientific lines made alike in the general .planning of elevators. In their nHchand equipment, and in the adaptation of a higher class of stnictta'al materials,it has come about that the day of pioneer empiric in elevator building haspassed. The materials out of vdiich elevators, are now built, such as steel andconcrete, are not only costly, but their successful use requires scientific desand a high degree df skill in their employment. It is not only difficult, butimpossible at any reasonable coot to rectify serious blunders due to errors inafter the v/ork is under way. i;levator designing and buildinj: is now a hi^lydeveloped specialty, and a class of work uhich should only be entrusted to respsible spccialiBts.

There are nov/ several materials employed in constructing fire-resistior fireproof elevators, ^ilthough steel makes the least risiatance to fire, yetstated above, it was the first material to bo used- ^here am numerous notablecases on record v;here steel elevators were utterly destroyed by fire originatinin their ovm walls. Steel is a hi^ conductor of heat, and when grain tanks arbuilt of it, it is used in very thin sheets. This makes it unfit in many instato protect grain from damage even though the fire is not of sufficient intensitdestroy the tanks themselves. In this way the contents of several tank elevatohave been damaged to a large extent by adjacent fires, which would not have injeven a vvooden elevator similarly located.

As soon as engineers reach the stage wliere they were able to scientifcalculate grain pressures and could consequently desl,^ elevator structures intgently, the other types of construction, such as concrete, tile and brick, canielise . Of the three tjrpes, concrete undoubtedly will bear the closest inppectionand v/ill pass the highest examination. V/hen made into final structure for^i it


14/70


15/70

-4

of maintenance is practically a neglici'ble factor. Being denser end freer froporosity, it has greaber waterproof qualities, but the greatest virtue of concis that it is a poor conductor of heat, and therefore, at all times preserves{jrain contents of s tank at a more unifonr. teinperaturo, and coinplotely protectit in case of fire.

Crick, thecretically is a good material with v/hich to build tanks,hut practically it is ordinarily found to be too costly, and in addition. In o

beto use cornrnerciol sizes, the walls have to/nade so thick that they occupy toorrsuch vrilusblp ground space.

Tile is an admirable noterial for roofs, floors end for fireproofingstructural steol and in addition has been enrplo-^ed to a considerable extent fograin tanks. A single piece of tile will stand greater compression than a piecof concrete of similar dimensions, and possesses equal fire resisting qualitiebut because tile is mede y?ith hollow spaces surrounded by thin v/alls embedded

mortar, the resulting construction is not nearly so strong as a homogeneousconcrete wall. As compared with concrete, the chief disadvantage found in theuse of tile is tliat is practipally iinpossible to build c grain elevator of thinaterial and have it absolutely , nteirroof, and the periodical repointing andrex^ainting of tile tanks which has been found necessary to keep out the elemenis very eiipensive, and a strong argument to shov: v*iy this type of constructionv.-ill lose 77hstever popularity it now possesses. Already several concrete j>ddto existing tile elevators have been built, and many ovmers of. tile tanks haveabandoned this type of construction for concrete.

The comparative cost of elevators built of steel, tile, brick and codepends entirely Ui;on the design of the' elevator snd the locality in which itsituated. T-teel, tile and brick often have to be hauled long distances from


16/70


17/70


18/70


19/70

to fireproof the 7700d v;ith sheet iron, but dr:' rot ensued and almost ruined thehouse.

V.'hile losses and iUsasters have on the one "nand rpsulted from ignorancof engineering principles, it has on the other hand developed that too much atrhas been laid upon theories, resultinf^ in elevator plena too elaborate, toocumbersome, and consequently \vssteful of material and money.

I'rogress in construction of concrete bins for grain storage was retardfor several years by the bursting of several large concrete grain elevators. Anotable example of one failure vrar a concrete grain elevator located at SpringfiIlls., as the grain w-as v/ithdravm from the bin it 'loft almost a perfect vacuumv/ithin the bin, thus cresting an enormous cutside pressure on the t.-sII, \7hichcaused its failure. li^uir.ination of the drav/inr^s for this particular elevatorshow that the enginO'-.-r in charge had carelessly neglected to consider this forceReliable contractors may bo thoroughly depended upon to build a structure which

in every way v/ill b: strong enough to withstand every possible chance of failiireThere are no^v in the elevator business, at least a half dozen concerns 'Who havemade a specialty of concrete elevators and may be thorougiily relied upon, imongthis list may bo noted James Ste.'-srt S: Company, John S. Eetcalf Company, I'cDonar.nginoering Conr^iany, Stevens Engineering Company, and Burrell "ESigineering Compan


20/70


21/70

^1^

OPETJ^TIOE OF iiiirnLEiG G?u\i:: i:t a gp.aif j:l.^vatop..Grain is delivered to the elevator in two waye: nanely, by raeans of

boat or by noens of railroad cars, however in sraell country to^ms grain is de-livered to the elevator by mesns of wagons. 77e shall first consider the deliverof rjrain by boat.

The reception of the grain by the elevator is carried on through a 'uiarine tower, vjhich is a tall and. usually square building, constructed of concreor steel, but preferably of concrete. The marine to7/er essentially cotisists ofa Iqq which by moans of machinery, is lo'wered dovTn into the hold of the boat toreceive the grain. It might be stated that a leg is an enclosed belt conveyoron v.hich is attsched steel bVi-okets, by means of v*iich, 'when eet in motion delivethe grain to the marine tovrer. /la the grain is v/ithdrawn from the boat it gradually rises, but the elevator leg is so constructed that it can be adjusted for aposition of the boat. From the elevator leg the grain is spouted into a garnerand then into a scale v^cre it is weighed, 'from v/hich it is spouted onto a beltconveyor, viiich in turn delivers the grain to the elevator, vrhere it is tSccivodby the receiving leg and hence lofted to the top of the elevator and spouteo inta garner, tiien into a scale where it is v.eighed, whence it is delivered into itsproper bin. Some marine to'VTers, hov/ever, do not contain a scsle, as the scaleis placed in the elevrtor and the wei^iing done' there.

I'ext let us consider the reception of grain by rsilroed cars. Inconnection with large elevators it is customary to run tv/o or three tracks, addas mapy as six alongside of the elevators, the tracks being ordinarily 16 ft.


22/70


23/70

=8

interioclcln{j slides v.'hich are operated Jrom the track level and onatles the graioperator to regulate the lolivcry of the grain from the receiving hoppers onto tconveyor 'belt, vJiich is located underneath the ateol hoppers, isbich delivers the

grain to the elevator leg, whence it is lofted to the top of the elevator, gpoutinto the gamer and weighed in a scale located directly below tbs gamer, from

it is delivered "by neena of a Kayo spout to its proper bin. The car isover the receiving hoppers and the door of the car broken in, allowing th

rain to fall through the steel ':ratlngs which are placed on 8 level wlt2i:the:rack into the hoppers. The breakinj^ of the door however, does not by any means

sjlltbe grain, but by means of en improved device, known as the ClarkGhovel, it is possible to scrape the remaining grain from the car in e ver

hort time. It mi^^ht be stated hero to give the reader an idea of h6w swiftlycar can be unloaded, that a car of grain containing 20C0 bushels can bo unload

iv. fifteen minutes, or at the rate of 8C,C0C bushels in a ten hour day.wlien the grain is ready for shijment, it is draTm from the bins by mea

a lording spout, v^iich delivers the grain directly to a shipping leg or in- .by means of a sc^ov/ conveyor or a belt conveyor. The shipping left lofts

the grain to the top of the elevator, delivers it into the gamers, hence intohe scales v.'here it is v.-eighed and then transferred by means of a oar spoat i^to

car or a dock spout into the boat. It might be stated here vAat is meant bythe tern garner. A garner is nothing but a bin located above the scale. It is

-.vith a series of discharge valves, which vhen opened, deliver the grainnto the scale in less tlian two minutes, 'ivhen the scale is filled the-discharge

are shut and the grain weighed , gencc delivered to its des.tination. Itbo noted ho're that the turner serves the purpose of collectiog the raln .weigJiings are bein- made and in this v,ay the grain may be received or ship


24/70


25/70

-9-^

f grain in ivhat is tonr.ed a transfer house, which Js a means of trtneferringgrain from one railroad to another or from a rrilrosd car to s boat or

ica versa, -here are other kinds of elcvotior'* in .7hich the :?-3in is preparedrailllntj and other coiamercial usages, ^he grain as received froD the farmers

a lot of foreign naterial, such as- straw, sticks and stonee end it alsoas high as 15^ moisture. To clean the grain end to sepnrate the variou

of grain from one another, it becomes necessary to run, the grain throughmachines as screeners, seijorators and scoxjrers. Those oschincs, howeverscrording to the kind of grain which is handled. 7o remove the moisture

from the grain it is necessary to heat the grain in iivhat is termed a dxuer housen which the grain is heated and retained ct fi sufficient temperature to removethe moisture, to v/ithin 1 or Zp. After the grain has undergone this special

it is conveyed into its proper bin to T?8lt for further shipment.


26/70


27/70

/^'6 '

zy-y^ ôuy-yz:)^z7o/y ^z^.^- 77//^ yyyjôzKE^ z?y^ y=ycî^y^z/y


28/70

/


29/70

"

a/=- C6//=^ZPZ^


30/70


31/70

-1

/='0/r' ^ o^z:> ozy c z>.y z"-^^^/^ o^^e'^^7^ :^//^yy'o^ i^crc^.-y'T-^cr?^ zio z='j5.iLy=p^oz^y=cyyr^^yyz>z^ZPy^^ ^0^0^^


32/70


33/70

-

Z2^^/


34/70


35/70

-1

- y^/A/r/d:^ y^C?/^ Z:^/^AX'.^ -

7~?=?/^/7y^yF/r.^^:> y>-yyy^ypuL y^ yypyyy^ /\5~J(:^cy^iy. cB e^^:? ^ 9/c^

y 9^(=? T^ ^2


36/70


37/70

-1

/=yz//y^ /=i:?/p j^o/pata/o^^^

- .7:5' X//!xJ^'^/^^"^- . 7^X //e5'^ -F^S" -V y:5'C>

. y. S"^ . d'j< //c^^ yS'^xyj^>: y


38/70


39/70

-1

7?9/y^ /Fyf//y/^o/Fc//y


40/70


41/70

"17-

-^ 9-^-7'


42/70


43/70

-

/:2f^/(5yY o/=- _ ^.

>5>=r^5V^r^v >3>y^:?>-^^'^>&- cr^yy^/rycD/^ ga^ g


44/70


45/70

-19

cri:P,p/x^^ - /c^^^ ^ J~ /zo- (^^AtjJ 3- -< /^J~x/J'O^ = /^^^

^6//

97-S

_. /


46/70


47/70

-20

ir-'-^^^^j^^.^^^^^^ yôo^ cr/y7y/^^^^/::^

^

ÔO 7c?;^^z zo^^::p ^^y^Zyyrfy^ô^y=^^c

jy^~5~/cp/y c^y^ cr^^^^y^ y=zaay^


48/70


49/70

-2 J

"^Ij^ 7a J5yh^^^^. d\/7\7\zo\^^'^4\3^


50/70


51/70

-22-

a^'-'Mfyy. ''7^^ w/ vyy^y^ ' /J~"^ ^CP'^ '

I III' I M- I'M' 1^

'^arm^"

c/fcf^s ^^c:r/


52/70


53/70

-2J-

yc:?G ^^ ^Z"2__ ^ I


54/70


55/70


56/70


57/70


58/70


59/70

F^l


60/70

(i)@o

-|^--#^)-^-0-e-6Q

J

QO (^cV.' V^ V' "O" Vi/ vp" v-^ ^-^ V^ V-' \s>x) o 6 6-e->-e-e-(HS)^ê-e-^Mp Q O Q C ) Q-(

^99 c^ô 096-e-^M ) cb o r ^ ^S06 9

) 9-9 9 9-(^^6-e-6-(^-6 6 cj) 6 6 9 o 9 cb-cb 0-6-

> -(b-- 90- o o-/e-Hb-e-0-^KMM) 6 (km ) 9 9,/( ) 006 -6 0- CMp-9^X^^>^^>-'^ Ve-)-9-^-G^6-c)-aH^^^(H:^9-K>-. ^ ^ X -) o 9 o CM ) 6 (j) o 9 9

. , ^ , ) o 9 (M^0-0^-([>9000"C>^0 O O-0-6KD 0-0'^ ) ^&^0-^0-0-0-9^-0 -{^^^9 c|>^9 009999^3)-0-0-â0^(0-O--^^H|>^^>-0-0-^^^^\gk0-o^ 0009096 0-^^ 9 9 rb 0-4^

I

N^0-o0-0 6060 -0-9-^ 9699 w/I II'^ j- y 00000 &^-^ 0990090 ^ ' "yê-0- 000000000009090 ^xl/Ô-0- 000 000 G)000O00cj)cb (pX ,^-0-0-0- 0000000000690000 90>0-^^^^^ o 000000 o-@ 00900009 o 9

^1^:0 00 00 -0-0-0^^-0-9-9-9-0 ^9l9"i0^0-0-0-0-0-0 6-0 o o 9-^)-o^-9 9 o 9 90 C00 Q-eô o 00 o 6 o o 9 9 o 9 Iv!>


61/70


62/70

J

^ /7


63/70


64/70


65/70


66/70


67/70

^ S- ;ivvHm

g

SS

1^

s

si.^11^111


68/70

I

I

I

StS

la

i^


69/70

iiii^


70/70