Complete Geotechnical Engineering Notes – GEOTECH 1 to 5, Study notes of Geotechnical Engineering

Download Complete Geotechnical Engineering Notes – GEOTECH 1 to 5 and more Study notes Geotechnical Engineering in PDF only on Docsity!

* CHAPTER 4: INTRODUCTION J 4 = NECTION {1 CEOTECHNICAL ENGINEERING GEOTECHNICAL ENGINEERING ie a cubdiscipline oF civil engineering that Involves engineering behawiOr OF earth materials: It includes the application oF the principles op Coil mechanics to the design of Foundation » retaining ctructures and earth ctructures: > ROck MECHANICS ~ Is @ branch of ecience that deale with the study of the properties OF rocks: It is a discipline that uses the principles oF mechamcs to describe the behavior oF rock mags , Which comprises intact rock matenals and adtscontinurties present therein- OBJEC TINES OF ROCK MECHANICS 1) Physio - mechanical propertixe of intact rock , rock mags » Joints, and other Form of discontinurtes - z Behavior of ctructures made in rock mass under various loading conditions uch ag in w-situ tress , blasting. earthquake ,and others. 3. Mechanism of rock Ppailures. 4 Crability OF rock wtructures , foundations of FOUNDATION ENGINEERING ~ An engineering discipline that invoNes the analysis and design oF foundations and otner ctructures located on, im, or adjacent to the ground: It is used +0 analyze and decign wtructures cuch as buildings, bridges, dams , and gor the design of roads, railways ,and other transport cy CLASSICAL PERIOD - PHASE 1 (llTy- (%56) - During this period, most op tne developments {n the area oF geotechnical engineering came From engineers and ccrenticte in France: 4 CHARLES AUGUSTIN COULUMB (1136- IBow) ~ French scienti¢t who uced the Principles oF calculus por maxima and minima to determine the true position OF the c\iding surface in soil behind retaining wall. In this analysis, he used the laws of Friction and cohesion For cold bodies. S JAc@ues PREDERIC FRANCAIS (1115 - 1822.) and CLAUDE LOUIS MARIE NANIER (1785-1836) - French Engineer and French Applied Mechanics professor who wtudied Special caves of Coulumb’s work velafed to inclined vactrills and back Fille supporhng wurcharge \oade. G Jean VICTOR PONCELET (IBB- IB) ~ An Army Engineer and professor op mechanics , who extended coulumb's theory by providing a graphical method for determining the magnitude oF lateral earth precsuve on vertical and inclined retaining walls with arbitrarily vroken polygonal ground urfaces- He provided the Finct ultimate beariig-capacity theory For hallow Foundations. CamScanner g KARL TERZACHI CI@O3~-19v3)— AN Austrian geotechnical engineer and geologist whe developed tne theory of consolidations For clays. te also ctucied tre belavior oF woils and wettement op clays agd on the Failuye due to piping in cand uncer cams. He is Known today uy oF Modern Soi} Mechanics’. > SECTECHNICAL ENGINEERING AFTER 1927. Am S aRtHUR cASAGRANDE Qaol-taer) - An America igieer who developed an ingenious decigne of woil testing tap wis and Fundamental recearch on ceepage and soil Wqueraction- RALPH PECK CIqiz- 2008) - An American citi! engieer who ctudied tach. pressure meacsuremente in open cuts SECTION 3: ORIGIN OF SoIL ~/ > WEATHERING ~ 1s te process oF breaking down ri minerals intu smaller pieces: Once a rock has ween broken do: ese called erosion transports He bits oF rock and minerals aw ing’ agents ke water, glacier, air, gravity, etx. 6 through which large rocks are MECHANICAL WEATHERING ic the Pp ritctec by phycical means, this includes broken down intd Mereasingly « abrasion , Frost acton or i and expoliahon: It ig alco reperted to as physical weathering. a: Abrasion — Rocks gin be Oroke® up by gichon and continuous. impact with other rocks during trag€pogfatign A rock Fragment carried along in the raging currents oF a river Puously cube itselp against other fragments » Tas uty can also oceuy e wind and glacial transportation. b. Frost Action ce Wedging - ik a collective term For variouc procecces that involves - proces includes : I Free: law — o ict a: Ing. This pro aes place within the pore cpacec oF rocks , the accumulation 1 easingly grows ac they draw liquid water rom +he curvounding oF por the continuous growth of ‘ice weakens tne rock and eventually breaking up- © Exroliation - When the overlying boulder are stripped by abrasion and offer Grosion mechanisms, they cauced the underlying rocks parallel to the wurgace 1 crack, Fracture, and expand , concequently , the underlying rocks releace the pressure in them: cheete of rock peel away From the tripped rocks and disintegrates ‘te smaller Fragments along {we Fractures. CamScanner CHEMICAL WEATHERING Is the weakening and cubsequent disintegration OF rock by chemical reactions. his procece either Form or dectroy mien tous altering the nature of the rock's mineral composition. Temper, and moicture are critical For chemical weatnering~ This occurs mor tn hot, humid climatic region. Chemical weathering includes oxi hydreton , carbonation , and hycronsic- > TRANSPORTATION D ~ \e he movement of material acroce the earti's curpace fy water, wind , Ice , Or gravity: It includes physical procesces oF traction(dy ging ), Sucpencion , and «altation. Te matertal nof{ carried away may be ert behind as a lag deposit. Twancportation and weatherir e the two phaces of erosion: Transported «oils are coils thot are podnd at locerhone. Far removed From their place oF mw Aeolian Soil§ - oil transported by wind. Glacial coile ~ «oil trancported by glacjerc. colluvial. vile - Soil transported by the mov m Wigh elevarhons to lowtr elevations due +o gramigy- Alluvial Coils — Soils transported by run r DEPOS! TON > Ie the geological process in which Ms, coil and rocks are added to 4 landgorm or land masc. Wind , water, and gravity transport previoucly weathered materials: Dune ~ A mound of WATER | ca tURATED A SAL OIL OF W 0494) _ Ya 2. POROSITY »n = 5: AIR VOID RATIO » Ng = - n=o Na= 0 Va20 a a* ] Ofna+i azl Nae | Va~ Vr 3- DECREE oF ~ geO =O dry wad. eo) IW wat Gond+ Reo WH O66L4 WEIGHT TIONSHIP Ww me & MOISTURE CONTENT, W = ae a Wo Ww=O 9 dry wod- we Wow = Ws Wri Ww >We 0AWL 6) CamScanner WRIcCHT -VO.UME RELATIONSHIP te BULK/ TOTAL / MASC/ WET / MOIGT UNIT WEIGHT /DENSITY mh ee ye Be PRY UNIT WEIGHT / pen TY ws. Nd Nae ee a SATURATED UNIT WEICHT ke ERFECT VE / BUOYANT/ CUBMERGED UNIT WEIGHT Ye Weubmerged . We- Sws Vr 1 BULK SPECIFIC GRAVITY. . % Gu ww ®. DORN SPECIFIC GRAVITY Qe d = 2 a 2 w c £ | = g isd & 2 o g a s & Aa B Gg = a w 4. SPECIFIC CRAVITY OF JOLI 6g = Ow SPECIAL RELATIONS! er ca UNIT WELT: Get Se B= Getse e % The OW 2 ne { . vo Se 3: Ser 4 Ye Gs Craw) Ctr) Bw 46+tas 4 8 = Bd t nSvw 5 Na = ha se B= Bd (1+W) Veaq = “SBE (Sy @ ary Condition + We Vs ¢ = 4-8) ms + Gag Wer? > |v00 K9|m3 = (Glee = (44 9S} ed SUBMER-CED UNIT WEIGHT: ot. eet ; OW = pen tw 2 Y= Xsat -¥%w DEY UNIT WEIGHT * kas Bde TEeé Sw 2 Fd = GeCl-n) ¥w SATURATED UNIT WEIGHT octet W Bsat= “Tee tw a ¥ = Xd nbw CamScanner ¢ EFFECTIVE UNIT WEIGHT, Z'-= at Swi Ws- Swe p soe We wl ie Vr Ge Fp =e ety 7 ON. ye We= Swe GsVeSw'= Wwe 2 Cos) ye¥w Ged nn Nr Ns + Ww : Ve t ee =. Tte oO - 1. Geel tos ; a eS Os ¥ ire ON &s «DRY UNIT WEIGHT » Sd = Ee SW = We ~ SS .._Ws _ Ww. ge WW a= Ur Gem Er = Bed OW Tw) © NE _ WS 2 Gs VeSW Cane RW Xd Ve Ve + Ww Vor eye Gs Xd= Tye OW 6) CamScanner SAMPLE PROBLEMS: 1. Derive. the Following relations using only the bacte vatioc FX gay = 2 av SOLUTION: a Wet 4, Ww ow - Ww Besar Te W- ee 0 Vr — Bw ay Kcat = sat . Wiiwe . aes = we(uti)n = (tin = a Ww vr n Gw eww Ws ws = Wt = WH) Un) <= tt) BE new ow Gs ¥sat > (wt) (4p) nyw & ge ¥a (Ie Zz SOLUTION : Ns 1 Woubm We - 6WVs We _ % _._ WS = eo OE gs Xd = Os ee 8 Vt Vr ¥ Vr ow Voow ae - - -| Ys yi Newlin _ He KwVe _ GeleBw= We ven ( ee ) a td (AH Nem) Nt Vy Vr ao” B= Xd -@) & ye Yd + (n-Na) Sw SOAITION © ai Wr ey yqe WE es neh ey ng 4 > we Be Bde Nea Ma aE Vw) ¥- tt = BS'h % 0-35 Ve © N= Va -W = 150 tm? ~7Sem> - 327¢m3 Vor 348 em? W Va + Ww ee \e — san? + 327un3 348cum* le = 15S 6) CamScanner ‘ A cample . oF. co[ hac a volume oF 305-cm? and wac tected i the laboratory... Water. ic.added 40 the ample to reach the caturation oF 20% and Gd'h and the weights increased 1) 682g. and. Jo1-g .recpectwely- Determine the Following * oo a Specigic gravity. of the wail solids , Cc. _. CINEN] Vy = 835 em a b- Wlume, of the «oil colide in em?., VE ee SE 20 OBRG. co Density in glec., at vaturation of qo . = SPL yas tog d- Moisture content at full caturation, ia % SOLUTION» a. Specific gravity of the coil wirds, es Ye os te Sw tfFe. @ 20% Saturation s+ @ GU Saturahon oe2g Gs t 0-28 0) ToIg Ss tose i) 35 cm> Ire 335 cm> ite 2-036(1te) = Gs 4-O-LE : 2-10 + 2Hloe = os + 0-Ge Gs + (0-4 2-030)e = 2-036 : Ge + (05-21 )e = 240 . Gs = 263% > A € = 0327 6 @ Full caturation (¢ =!) Pe : feat - 9-036“ ll0-2-vay Ge t& Tose D-S-Or8 kat = W 2 {10 Ite f f feat = 2-233 sem? oq _ A + ste ('glee) : $35 cm> ( post ft 2 -@- ~ feat = 2-234 glom? 1 ' 1 ‘ On os \ b- Volume op the woil colds | Vc yew tNXs Ve = as . Ww i¢e 335 cem% « W -e 335 ea) 335 = W te at ; Vo = 2$2-44q om W = 82-551 cm? Ve = V-Vv = 335- 2.55) Vc * 252-449 cm? 6) CamScanner eet We > WEs ; vo (se) = onoise (2-wat) x boo ee TU Nia a Ss | & Wwf be evaporated per cubic meter op wil to attain 5% cafuration , 1 cm? A 4A i | ; € Mi _ Me 2 _Mw cevap) vy Vv Vv ft — f= Pulevap) 2 AB ot - oN _ 24th (2eary UE AUF ode) = rps - 7 a Gc te 2-64) + 0-5 f= ae fa = 3 Bs tT gee e=-O-Wp > & futevap) = f - fe @ saturation = 0 = Bt FM glee [920 - Sie = 0-S2BI gfe bulevap) ~ 0-093 glee ? , tnater (trop) = 32605 4-352 - 43000 &/m? 6) CamScanner e& @ & C @ The. embankment for a highway 4850 ft long , 125° ft top width and St in compacted thickness with cide clopes. op 2V: 3H ie tv be conctructed From a candy coil trucked. From. a borrow pit. The Water content of the candy voi in the borrow pit tc 9-55] and ite porosity is 0-450. The specificertion requires the embankment be compacted to a dry unit werght op I20.68 lit” lp the Specific gravity. oF. the woil colds Ic 2:75, determine the Following : a Total Weight oF Cdi| «olids. required , in Kips. b. Nolume of «oil required ¢fom the borrow wite, in f°. c Nolume of soil, in 4, required from tre borrow «ite ip the Free Well ic 1B d- Weight of Water, in lb, ty ve added per Foot tength of the embankment to veach 2% mvisture content. SOLUTION exe be GS IS FIXED Vin-sita 7 EMBANKMENT: Pi BORROW PIT’ cy 4 “ ‘ wre ee Ie? 5 Xa > Hoe $8 {ft wr 58h = ‘ n= 0-480 [— 1s! p= 125' 4-75" a Wr of coil colids , Kips Le Nema = 4 (125+ 4b)(5)(4 850) = 3 213 125-4 I. Xg= Yemb Ws 6% "gs - ——-—__ {20-6 i 520 125 2 We* 387 438-i25 Kips | b NO ~ n o-450 re _— “ Vee |e Cr > Doyen ~ OBB (er) FOR ©! , Gs 3 219 125 44 .? s %b 7 BP Tre V+ 0-423 Tt Ob 2-18 0-8 = (u2-4) Vee = 4 105 032-502 #4?) e = 0-423 (eis) CamScanner PRACTICE PROBLEMS + yo % = 3-793 Hite ye tes Yee? W = 12-41% : we B01 OLUTION + _ 6c (itw) J : : Sgt ve 8° Tre OM %* wee ing. 74g ©. GEL1# O-104)) og + 0738 TPE (ond) Ie 1s = = —— (2-4) 123-743 $:123-7d3e = +1241 Gc (02-4) NF (OG E MTeigGe = G2qes + MB.72€ JON4GOYGe — 193-3 e ~ 123-743 —» () wt-4os -98-duSe = 117185 —» © Ge = 2°BIZB -A- ewe = OGONG -6 Ge te Xsat = Tre” Sw A t+ 8 Se (02-4) Neat = 193: 7154 ies? | SMS ow » Mz op 5 ee ~ 2048 Y M OLUTION, Vs) Ge te TJ 7 Ovo frat = ye fw Vs : =O ~ 2:54B + O-0u7 kg Ww Vs OG ~ lt O-@o7 (1ov0 hn’) Vs = O-GW ++ 0-Wvs | kot 7 1928- @lY ¥9/m? O-Gve = O-GW —J W = 0-GGFNs e = WL, OGUTVe Ns Vs € = 0- GF 6) CamScanner oe me dag coe 270 ee 45h 204g — Volume op Water ty. be added to the volume of woil ty teach full waturation (in cm?) SOLUTION ! @ 45) saturation @ \0'/ saturation Vy = Vw ~ SS tse : ve ON ong) e=4 fg. 5 EES EE (9) ao Vr @ 48% caturrtion V S 50: ; —_> : : ; Nw. : T= 450-059 —- © ce _ Ww t 048 “45 = Riedy nme ee SW 2 o.gay: : O45 = Vt Ite. 1-48 oeey > @ : & Ae Ne . Nw.> 36-499 8 W = 81-00 --?-© \w (Added) ~ Z1100 - 86-495 Ww (added) = 4q.G0S em? 6) CamScanner