—_ —— —_ — —— .— .— __ .— — —-—— .— .— —— ——__ —— DESIGN AND CONSTRUCTION or . TBEADOMETER _ THESIS .103 THE DEGREE up 3. s, C.~ A. BoWser ' R. T. DeFant w. R. IPaddiso'n ' 1933 /)(-— 7 ’11, (| i ‘ a. m b 5‘31“}! I ”ELEMENTARY . + MIKEOBLQ‘CER i ‘ 9 § 2‘ 3 I €Av’ \ I‘. 9“!" fis' 5"“ cfi\7,fimnf~, ‘m -‘7 HA; J.” AMI” VLIDALsn/V .- VA! CF [PEA C:-:—:L~R .. t l A "1‘- I ‘ O ‘- Q A -d 818 Saomltbea to F“, . *1e Facultr of srT ‘1. r‘ In.“v ma mq- AT T‘f‘" “.‘IU‘; \TI¥;I' ‘n.._4 \JA'J Jada—d , A 1“?” fTYMT‘ I Q” n‘-“ T Tray-WW Bu?» vv—AJ.UZIJ: AME AffLLD 50... L V... Charles A. Bowser Ra"man3 T. Dchnt ”.3. readiSOn June 1033 THEStS V v in ,‘ .- 9 V5.1‘ ‘1‘... .1 giving a r-.' {rs-gent; I! .u Tneas TREADO;EIE Located at East Lansing, Michigan IL‘»! 'Ha.’ “‘axm -_- "443:! A C K N O W L E D G M H T The writers wish to take this Opportunity to express their deep gratitude and appreciation to Professor 0. L. Allen, Professor L. J. Rothgery, of the Civil Engineering Department of Kichigan State College, for the aid and guidance in our work; and also to Mr. W. L. Watt, of the Mechanical Engineering Department, and the Buildings end Grounds Department for their help and use of tools and machinery. 94109 bLh' P4 II.tIIu 1-. . IlltroeruCtionooooo0000.00.00...on... Design and Construction- “ O - -.~ '3 569133.11 c CORGlllSiOfl'OO'OOOOOOOOOOooona tr] Power Car. gn an X -. ‘ b a —\l ‘. D liti‘lll I‘. l\ nilllllll I N T R O D U C T I O K Technical progress is determined by comparative investigations. Certain means and installations are necessary to enable tests to he made and repeated under conditions identical with those found in the practical every day use of the material under investigation or examina- tion. From that standpoint a treadometer has been designed and con- structed. A treadometer may he defined as a suitable road testing machine for determining the stability of different types of bituminous surfaces. The design and construction of a treadcmeter is new in the field of testing of bituminous surfaces. The first treadometer was built at the Technical University in Stuttgart, Germany, in 1327. This machine is built on the principle of a truck of 18,700 pounds. The frame is mounted with suitable strong Springs on axles of the four wheels. "he uh..- 1 frame mounted on the eccentric rotating Spindle prevents the sheels from traversing in the same path. The Operation can be continuous or alterna ing and also at various Speeds. When rolling down the crushed stone iron wheels are used instead of rubber tires. _Another machine was built by the Hational Crushed Stone Associa- tion of Washington, D.C. in 1931. This machine works on the principle of one arm rotating about an axle. To ohtain.uniform wearing it has an arm that slides hack and forth in a guide case. This sliding is made possible with a radial motion screw. This arm is kept level by an elevating screw at the end of the arm. One point of interest is that the rutter-tired wheel is slanted inward at the top. This produces less wearing on the track then when the wheel is vertical. The machine has 1. various Speeds and can be reversed mechanicallv. An iron wheel is used to roll down the material and the rubber-tired wheel is used for testing. A third machine was designed by the Institute for Road Construc- tion, at Karluche, Germany. This machine is constructed of eight huge steel guides, with eight heavy motor truck wheels forming four two-wheel chassis at the outer edge. Wheels of different types and weights can be employed in the test. Economy has become of prime importance to all State and County highway departments. Construction and maintenance engineers are more than ever interested in reducing expenditures in their departments. hany believe that a new era is at hand in which low-cost roads will re- ceive a great deal of attention. Accordingly, a new treadometer has been designed and constructed to determine the durability of economical bituminous surfaces. Th machine is located in the Civil Engineerin, Experimental Laboratory at Olds Hall of Engineering, hichigan State College. Before actual construction of a maximum diameter track could be started an old treadometer track had to be removed. The discussion will be limited to the following: Design and construction of track, test car, and power car. EESIGH AID CCISTEUCT CU OE‘THE TnACK The old treadometer traclt was removedc nd tne largest diameter tracn po ossible to be fitted into the location was determined. This was done by maxing a plan view of the la cor atory showi ng the locatiin of the walls, cclwnns, T-be HIS, girders, an? electric lights. (See figure 1.) The largest possible diameter tra ck was found to be 15 feet 3 inches. The center of the track was then located on the ceiling ani floor. (See figure 3.) Having salvaged the 2 inch C.R.S. shaft previously used, it was decided to use that as a center shaft. This shaft ves imce lded in a circular concrete base 2h inches in diameter and 12 1/2 inches high. The form for tr is be econsisted of base boards cut to fonn a 2% inch circle with sheet metal nailed to the base boards to form a cylinder. 1ne c nstruction of this form and th method of plumbing the shaft is illustrated in figures 2 and 3. Upon centering the shaft an form, 3000 pound per square inch concrete was poured. Havin gr already deteniined the cross-section of the track, the various diameters were marked upon the floor by using chzlkrand a tape. This gave the prOper curve of the form lines and by using sheet metal teiplates v:ere rade to fit the form lines of the various diameters. The base boards were wade frozn these te plates. The forQSIvere built to cover one- -oua.rter of he entire track and ea .ch ouarter was divided up into segments.( See fi*ur, 3 for details of cone struction.) The base- / V boards were made of l" x 6" white pine. To preperly Suace the oase- baords 2" x M" X 3" blocks and on the form lines 1" x 2" x 10" woodstrips w re used to brace baseboards and to serve as a back bra-ca for the sheet (I) \T\ _ l Tee -Z7eam.s7 girder —z_.... l; 00/: f0? W4// |//// \h \\\ 133W” 1“ f \‘~\_,- ‘ E “$5” 11/ ”iv _ j P4477 V/aw 0F- 65/4 INC7 JHow/xm pow rm H are TPEHDONE 75-2 W/ 7' H 1955/7567 70 COLON/V5 fig/Y-j / x01. my V/EW ; 60/ MA? Baje flea/”d; pun—- ——1 N’ --— P/{zé/y Mfe Mt T/mp 0F 2/. (/M elm; file/14F 7' / / 2/ F/dnqe of“ 7.309 4534/27 _/ /7. 1x I 7fi7/I/7I/JJI/lj/ll UVXV ,r7/ r/77 ////7/, We/y I: 7‘ BL\\ \.~\\\\\\\ \ \\\ \\\\\.\\ \RQ If]? 77}; “WV/ «$.wa w; WU..N ,AZWV/ W “0.. Co ’ ' .If-ED: n. ‘ Q 3... .\ .."’ wfi \l \ . x i / 5H OlV/A/G /"/£- 7H 00 0F Pl. (”val/V67 jiCT/O/Y Jam-'- r I .0 ‘4 l‘ 1.; r-0 ' metal. Sheet metal res used to give a better finish on the concrete. The inside form was braced by using radial bracing which was attached to the center post and gave the proper radius to the form. The outside fo~m was braced and spaced by means of Spacer' OJ 0 U :5 m P m C‘- P). :3 f 1 J C) *t H H. ‘3 OJ ,3 pipe - two to a section - laid upon the floor. The inside-inside and the inside-outside forms were huna from spacers connecting the inside and outside forms, and were properly Spaced by l" x 2" str *j. ’kJ U) ’3 D (D forms were oiled each time before pouring a section. The next procedure was to lav tne reiniorcing steel. One-half inch D bars were used in the track. Ei ht inch vertical dowel bars were Spaced two feet center to center in the curb, and the horizontal bars were Spaced three inches to center in each curb with one bar placed in the center of the track at mid-heighth of th L inch base. The steel in the be (0 e and outer curb has two inch 3 protection of concrete, and the inner curb has four inches protection of concrete. All inner sec— tions were tied with wire. (See figure M.) In each quarter section a two inch pipe was placed in the outer curb to drain the track. A field mix for 3000 pound per quare inch concrete was detennined and it was found to be as follows: 2h pounds of Portland cement, 30 pounds of fine aggre- ate, 85 pounds of coarse aggrera e, and 1 1/2 aallons of water per batch. \- (“z The M inch base was poured and then the inside forms were put in place and the curbs were poured. Each section was allowed to cure one week. The inside area between the track and the center post was then filled with clay and tamped, and a h inch concrete apron was placed over this. This apron wa marked off in eight equal sections. Later the track was given two coats of gray paint and on each section of the apron a n nber was placed in black uaint. For further construction details refer to M. _ fl nonnk ..N \\ .mim \ttntno mssv m “(MN \ s» .Q\%\. ting}. eh thhmwa N .M\\ \wuxm. \NQ .5 n..\ .... W\%bh1 Iebewmk Est ohm, rig. /‘/-€ 4 J- -—-—-——-—-,,0/ J nflkfixlx. In! NH W... N J? Em. A. it: E 5H,: : «we: ”I a c __ . w- ... s - 4 a . E N . not» S msiw ..... mwf Ken]... _ ”3m. 33%. M 9 . _ .C... . . . . 3 H I. N z. :11 F \“lL‘TAl $\ fr“ s§fl\ ‘rllllu§% IIIIIII.‘ . \ an i .VuK J.M\B.Nm; £9».an WQK nskhmux I ebQWtk EDI Um.“ Wbm 4K /////////////////A//////////.///////////////////////////~% ‘ .s Q‘ \ N - firm 3 u \\\t {WK.\ \ .IIIM W]~Nx\\ \ \wxxsw .. x N... 9. m \ \, SQ .. ..\ // r as / // \//r .. .. . ENNNNxVx‘EE N .. M .. N... \ <12...“ NAN mfiusk 3.. m2 Benn F75, 0’55 number of cuhic yards of concrete, cutie yards. \31 DESIGK AN; CCXSTIUCTICN OF P0723 CAR q The power car, including a tnree phase, three n.P. variable ‘0 speed slip-ring motor, and commutator was obtained from the wocemh County Road Commission. The hearing was placed on the two inch shaft and the power car attached. The power wheel uses the nine inch inside curb as a track. There were a few necessary changes made on the power car. The first change was a new conduit lending from the commutator to the motor. Another change was the placing of two 1" x E" angles on the frame and around the shaft to prevent the car from tipping and to help turn th. commutator arround with the car. The car was given two coats of gray paint. For further construction details see Plate I. nn- on - ow.“mfi a, or . Tflfl n» “Lola.“- 14...;- bc-.oinoo-lon 'cr .L.L.J T4101. UAR n 8 PD. The iesi n of the test car was made to give e sliding arm guide case so thzt the wheel and roller could traverse the entire track while in motion, and with an elevating screw to keep the car level at Q ce H- all times. Channels in the constru‘tion of the sliding arm and au case were found to be stronger end more economical. Th, Yotionel Cree 3‘ R -A “- o O '. 1: Q.. I' :A.~-r B W '5' O L: I ’ :q atone. SLuClathD used an “-ceeh for a s iuing crm, tulle their guide see is constructed the some as the one beinr described here. The cast r-' . . \.‘ C 0‘ iron tlock for the redial screw is held by angles tolted to the chennels Q of the guide case. The guide case is attecned to the power cer with two straps. See slates I and II. The channels for the sliding arm are held together by 1/?" ¢ bars 1 a 1 en: cy a pL H tte at the inner end. The nut for the radial screw is held I f ty two angles welded on the th channels. At the outer end is a yoke tolted to the Channels. See Plate III. The two angles of the yoke have slots on the outer leg upon which slides the main plate. Bolted to the main plete are the axle plates for the rubber-tired wheel or re ler. The axles for the theel or roller ere welded to the axle plates as: extend through the eleveting tlock. See Flats III. The rutter-tired wheel is Lake and the roller is a Novo Engine fly wheel in which 1".) O r.) U) C.- n. e stander iron tearing wss placed. For further details of axles, sliding arm, bearizr, and roller see Plates II, III and V. AC purpose of the elevating screw is to keep the test car Level at all times. The nut for the elevating screw is bolted to the yoke ard the block is holted to the mein plate. For details of nut end tlock see Plate II, end for elevating screw endt"heel see -lete IV. The purpose of track while in motion. case and the Jetails of nut,'block, A seat has teen case so that -71 A ClaCci m- .1 ‘ ' -A‘, I . ine neitnts are A ward at the tep. Ey s then when the wheel is t V is 8' Elate III. The car rte given two coats of the onereter gives a constent moment err. held in a vertical ‘L to keep tne wheel and roller traversing the entire The block.holdin§ the screw is held ty angles in nut is held ty angles and radial screw see Plate IV. installed on vwr 1 J.X(XZ), I“ extend or s test car as on the doing there will te end was nade ly slotting the holes in the N 9-... : x.- t. d 8. less shown in Plate I. The rutber-tired wneel weer on the yo‘zze . q < h a tne end 0: tne rerten the length of the arm. This reterial Th angle of slant See ygke assembly paint. C O N C L U S I O N The design and construction of the track, pater cer, eni test cer rzs teen covered in the discussion. The most satisfactory low cost roads of the future will he tuilt of mcteriels the have been under investigation, en ) ',.4 t‘.‘\ ere will he more cosperetion between the laboratories are the field enrineer. ”he use of a treedometer in testing the statilit< of bituminous surfaces will to yield rnch interesting information which will be of value to the hirh- / A It... I. - .‘t‘.’ A 7 I- s‘hnd. #1:: - Lie; 3 1.3"; ¢\o O. - ." 0.. J".5.. 9.‘ 0“! a0 '5'. n1 "W? 6-5.,- I".- . h. .‘It...‘.. 'jlo v 2?. .11th ..‘J ‘ .i' .0 o . .I 5‘. e ) \\\ E I R AH R B W I I .— STQ’E UNIV MICHIOQN