cay Lt SY 1g En VTE ¢ \= 1 B® PURBANCHAL UNIVERSITY 2019 \ B.E. (Civil) /Sixth Semester/ Final Time: 03:00 hrs. Full Marks: 80 /Pass Marks: 32 BEGS62CI: Foundation Engineering (New Course) Candidates are required to give their answers in their own words as far as practicable. All questions carry equal marks. The marks allotted for each sub-question is specified along its side. Assume suitable data if necessary. Answer FIVE questions. 5x16=80 ), What-are the general requirement of building foundation? What are the major objectives of site investigation? “444 A masonry retaining wall of trapezoidal section with the vertical face on the earth side 1.5 wide at the top and 3.5m wide at the base and is 6m high. It retains a sand fill sloping at_2 horizontal é) and J vertical above the top horiz unit weight of sand is 18KN/m® and @=35°. Find the maximum and minimum pressure atthe base of wall assuming unit weight of masonry as 24KN/m). Wit ter Che hy a 8 réSsion for active case and what are ‘he basic assumptions made by coulomb to derive his weseDg theory? Gy gy» 0K G2 Ny, A footing 3m x 3m is placed in a clay soil deposit at a depth of 2m. The undrained shear strength of soil is 6(0KN/m? and the ) unit weight is 20KN/m%. The footing is eccentrically loaded where iam / the ecterttricity of the load is 0.2m in one direction of the axis of “Jp / footing. The excavation is backfilled. Determine: 8 (i) The net ultimate bearing capacity 27 27 (ii) The net safe load for a safety factor of 4.7.77 a) Derive the expression for Terzaghi's ultimate bearing capacity of strip footing for general shear failure stating the assumptions 6 made during derivations. 37 ZL) ATK =e Scanned with CamScanner aol,"a _ ar . A 8m deep excavation is to be made using anchored sheet pile ll. The tie rod is placed at a distance 1.25m from the top with : spacing as $m/cc. The soil consists of sand with angle of > internal friction as 30 and unit weight of soil is 18KN/m°. Determine the depth of penetration using fixed earth support methods. Assume the contra flexure to be at a depth O(0.8m from the dredge line. 8 ap What is negative skin friction? Explain typical situation where negative skin friction may occur. How does negativeskin friction @) affect load carrying capacity of pile? aA O¢ 8 XG A pile group consists of 25 pile is driven into a deposit. The piles \7" are arranged in a square configuration that is 5 piles in each QAO, + direction. The center to center distances between the piles in 2 teas both directions are 2.4m. The length of the pile is 10m and the : diameter is 0.8m. The average undrained shear strength along the upper 5m length of the pile is~40KN/m?2. The average undrained strength along the lower length of pile i@QKN/m?. If adhesion factor is 0.6 for both layers, determine the wit load capacity of the pile group.” (2), Write down thé~.procedure to design raft fow conventional rigid method. ‘ weighing 49 KN and having an effdctive fall of ~ settlement per blow is 14mm. The Sy _ 12mm. Assuming the coefficient of re: 6. Write short notes on any FOUR: Na) Modes of foundation failure (b) Steps in design of spread foundation ) Components of a well foundation. {| Combined footing (e) Skin friction on pier shafts Scanned with CamScanner[ PURBANCHAL UNIVERSITY : 2018 B.E. (Civil)/Sixth Semester/Final Time: 03:00 hrs. Full Marks: 80 /Pass Marks:, BEG362CI: Foundation Engineering (New Course) to give their answers in their own words as far ' Candidates are required: as practicable. All questions carry equal marks. The marks allotted for each sub-question is specified along its side, Assume suitable data if necessary. Answer FIVE questions. 5x16=80 XQ id) A secand ring road is to be constructed in Kathmandu valley. SS Lyou are A\geotechnical engineer and you have Go do the site investigation. Riscuss the methods, soil samples and different SS. ts.thdt may be ie the types of foundations? Differentiate between shallow foundations. What are different, stages of site Discuss briefly. 2+2+4 rth pressure of cohesive soil using Rankine's Also enlist Rankine's Assumptions. oy tn its “base diameter carries load fa depth of 1.5 m i as he saturated unit weight of sand is m? and unit weight above the water table is 17 KN/m:. the safe load it can carry If the rater i oe Take saturated unit § Conta. ... tension crack. Scanned with CamScanner(2) 1 ' What. are the diferent types of mat foundations? Discuss about i i the factors i ting foundation? What.are of them. What is Noating ters affecting the depth of the spread foundation. . A circular conerete pile with diameter of 0.3m and 15m long is used. There is aand with dry unit weight of 17 KN/m% and internal frictional angle of 30° upto 5m depth below the ground 0? surface. After 5m depth there is clay with unit weight, of 20 ! KN/m3 and ncorffined compressive strength..of 100 KN/m3, a oe at thé depth of Sm below the ‘ground surface. Determine the ultimate load that the pile can carry. Take k=1 and «=0.6, + — ; . "8 J What are the methods of soil stabilization? Discuss about,any i of them. Draw a neat figure showing the various components of the well foundation, *1,5+2.5+4 By rrtermine the depth of e: ie rod of an ~~anchored sheét pile wall 6m. The tie Soil below the dredge line is cohesionless, Take internal frictional ; angle be 92° and unit weight of 19 KN/ma, 8° : “5. Write short notes on any FOUR: so al SPT test *W Proportioning of spread footing ¢} Negative skin fiction Pile load test : “G Beating capacity of pier in clay oo “ BCoffer dam : SS Scanned with CamScannerPURBANCHAL UNIVERSITY 2017 BE, (Civil/Sixth Semester/ Final ‘Time: 03:00 hrs. Full Marks: 80 /Pass Marks: 32 ; Foundation Engineering (New Course) Se BEG362 Candidates are required to give their answers in their own words as far as practicable. All questions carry equal marks. The marks allotted for each sub-question is specified along its side. Assume suitable cata if necessary. * . Answer FIVE questions, wo 5x16=80 Nye Mention different stages in site investigation along with its objectives. : 8 masonry gravity walls as seen Fig. I(b) is designed to support 3. The soil at the front and back of the wall is the same and ties are given in the figure. Calculate the safety factor i 2.5m ' Fig. 1(b) Contd. ... Scanned with CamScanner“(2) \ 2a) Derive the Coulomb's wedge expression for active case and what are the basic assumptions made by Coulomb to derive his wedge ry? footing to failure wht L= 2m, c5,0, $= 46°, | ng | ci 46° | 158.5, 2¢4)65 | Hansen the load reached 1863 KN. Given B= 0.5m, ( aN : 6+2 at took a rectangular wn 46° | 158.5 [$28.73 | Meyerhof eoYy °F oer Fig. 2(b) 63 KN , mS 3(a) What are the conditions for. the suitability of mat foundation? “= Also describe the design procedure of mat folundatign, 246 Determine ultimate carrying capacity of pile of dia. 0.3m and 10m. driven into sandy soil of given SPT data. Take y= 17 Se ie a N/m? and 4= 30°. 8 Nevalue [7= [10 [1 is (30 Depth fm OJ: -5m | 3m pm 12m it sketch, 8 4(a) Describe the components of well foundation wit} (b) Using free earth support method, determine the actual/design depth of embedment and force in the tie rod of an anchored'sheet ‘od is 1.2m below pile wall retaining soil back height 8m. The the top of the wall, The back fillkand the sdilpelow the dredge i = 33° and > 8 line is Cohesionless. Take ¢" Contd. -.. Scanned with CamScanner6. Ground surface Fig. 4(b) What are the various methods of Temoving ground water from Fe eRe sites? Describe three Prominent methods of ion s6il stabilization, 444 pot D driven into a soft clay extending fromyg a great dept . The diameter aa ere. 30 om and 10m respectively, The X the clay is 79 kPa. If the compute the allo : on the pile group on the basis of a sheaPYailure criterion ye for’ a factor of safety of 2.5. 3 é& | 4x46, i Write short notes 6n any FOUR: “X{a) Types of footing ~{b) Proportioning of footing for a settlement c) Pier foundation * | ig) Coffer-dam (e) Settlement of pile foundation Scanned with CamScannerPUNRDANUOAL ars vaawoae 2017 B.E. (Civil) /Sixth Semester/ Final Time: 03:00 hrs. Full Marks: 80 /Pass Marks: 32 BEG362CI: Foundation Engineering (New Course) Candidates are required to give their answ rs in their own words as fe: as practicable. ~ All questions carry equal marks, The marks allotted for eqch sub-question is specified along its side, Assume suitable data if necessary. Answer FIVE questions. . 5x16=8C (a), What are the objectives of soil exploration. Discuss types of soi investigation? . 44 (b) Determine. Rankine's active pressure per unit length of the wal fig 1]. Water table is at level 3m from base of the wall. é Fig. 1 Derive the expression for Tergaghi’s ultimate’ bearing capacity o strip footing for general shear failure stating the assumption: made during derivation... é A strip footing of width 1.2m with its base at 2m belowgrouns face. Take c#12kn/m2, unit wt of soil 7=I8kn/m3;zsat~ kn/m. Ne'=4/Nq'=8/Ny'=16, Determine ultimate _beariny | capacity if [a] Water table is at 1m below ground level. £ ) Describe active; passive and at rest condition of soil pressure ~ Describe different methods of soil stabilization. ate Nee Check stability of masonry retaining wall against sliding overturning & bearing |fig2|. Safe bearing’ capacity: of soil i: 200kn/m’ & coefficient of friction is 0.4. : t . . Contd. .. = $$$ $$ rr —— eee Scanned with CamScanner4(a)_ Write’ down Fig, 2 the procedure, to design Raft foundation by conventional Rigid method, - 8 (bl In Which condition negative skin friction is ‘developed in pile foundation is constructed? Describe, 444 Lam tiction pile group to carry load of 2000KN including wt. Se Ss n foundation?.How Pier cap is 60kn/m2, Siteywhere soil is uniform clay to depth of 20m Av. Ynconfined compressive strength of soil factoF of safety=3 & adhesion factor = 8 ~ Determine depth of embedment and force in tie rod of an anchored sheet pile wall retaining soil bank of 4m. height. The tie rod is located at meee top of wall, Take soil is Cohesion less with 30° & unit wt. 8kn/m3, 8 6. — Write short notes on any FOUR: © 4x4=16 aiTypes of CofferDam + fey Difference between Rankine and Coulomb earth pressure theory. ee SS SW 7 : above the water table. The backfill supports an. surcharge of 20KPa. Determine the magnitude application of active earth pressure, (eI Derive the expression of passive lateral Pressure using Rankine’ theory for (c, ¢) soils. and point c P) A circular footing is to be designed to carry a load of 6000 kN. [: £ the depth of foundation is 1.6m, determine the suitable size o | foundation with a factor of safety 3. The water table is at the foundation level. Take §=20°, Ni=11.8, Niq KN/m3, Yea=20 KN, _ Take e=20 kN/m?, Fal Ktm valley (metropolitan city] is planning to construct an oute: _ Ting road in the valley. For the purpose, a detailed soil survey has j to be conducted. As a geotechnical engineer, what will be your recommendation Tegarding the types of sample to be collected ; during subsurface exploitation? What kind of tests you are going , to perform with the recommended soil samples. in the laborato! for the design of ring road? 8 ) =3.9, N4YV=1.7, y= 16 2. Use Terzaghi's local shear failure theory s Scanned with CamScanner(2) () What do you ‘mean by combined footing and where do you ' provide it? Discuss the prdcedure for the design of the ; 8 trapezoidal footing. . » (a) Explain ‘the procedure of conducting the standard penetration: ~ ¥ test (SPT) in the field. Elaborate its importance. 8 A concrete pile 30cm diameter is driven into a medium dense oe 10 KN/m®, K=1,0, tan=9.70) for a depth of 10m, if water table is ‘2m below the ground surface, estimate the safe load taking a factor of safety of 3, 8 What do you mean by coffer dam? What are the various methods of removing ground water from construction sites? S{a) 2+6 () A Sm deep excavation of trench is carried out in sand and’ Stpported by cantilever sheet pile. The water table at both sides of the sheet pile is found at the bottom of the excavation. The , Bulk unit weight of sand is 18KN/m? above the water table and ' 2OkN/m? below the water table. §=30", determine the required depth of embedment, : 8 6. — Write short notes on any FOUR: 4x4=16 (@) Soil stabilization . x(} Combined footing (¢) Factors affecting bearing capacity of soil x{¢) Standard Penetration Test (SPT) * x) Types of pile ) Caisson fourtation oe : : Scanned with CamScanner~-FFWOPA ENGINEERING COLnEGE i sixth Semester Assessment - 2015) .B. E (Civil) /Sixth Semester + BEG362Cl, Foundation, Engineering 03:00 NS. 2072-06:12 . "_ "| PASS’MARKS:-"32 are required to give their answers in their own words as far as practicable, any Five questions. . Attempt 1.) explain, various ; method of in-situ ‘soil est. g (8) ) Determine Rankiné’s' active ‘pressure per tinit length of the wall {figi]. Water poole is at level 3m from base of the wall. e expression for Terzaghi’s ultimate bearing capacity of strip ) Caisson foundation, (c) Plate load test (d) Pile load test (e) CPT Test ( Types of Coffer Dam, R Scanned with CamScanner| BE. Sip siets Time: 03:00 hr: Candidates ¢ as Practicabl "All questions carry Sifaat is specified alons ts'Bi le Answer FIVE la) Desetibe'n met Scanned with CamScannerScanned with CamScanner“ : (3) ‘| “6a Write ‘types of well fo dation. “Describe: the various component _, (parts) of the open cal 3son with neat sketch: 1G Te B46! aiichored sheet pile wall rétaining soil bank of height Sm. The tie, rod.is located im below the‘top of the wall’ The backfill and the * soil below the ‘dredge ‘line is cohesioniess. -Take 9 = 30° & soil “unit weight as. 18 kN fim. i 8 - Determine the depth j iof embedment and force in tie Tod of | an Scanned with CamScannerScanned with CamScannerAEN oe wh Scanned with CamScannerOS . °6(a): What’ ‘are the Various methods of: remoying . a water trom * Describe! “three! ee E _ methods of oi] gartied gut in send and The’ ‘water table at both ottom of the excavation, +f Scanned with CamScannerScanned with CamScannerScanned with CamScannerthe depttt iT ‘embedment ‘of ‘eke. arichored: ‘sheet pile Determ shown in Figs 5(c). } 1 ‘ metre 0 of ise wall. Assume ‘free-earth support Condition: . 8 ae Lo l erm On35 vir PateKNs Onis . Fig. 5(c) “Assuming the mat‘is rigid, determine the soil pressure distribution “at point:A, B,.C ‘anid’ D if the size of the columns are 0. 6x0. 6m | PS The plan‘ ofa mat fouridation, with 9 columns is shown in Fig. 6(a). | Scanned with CamScannerScanned with CamScannerScanned with CamScanner“Yar 2 15,5 ees! #235 e085 yp = lepava = 38, ¢= 0.65, it nt and Ng=9S. The water table is inate load carrying capacity of 8 Scanned with CamScanner>) PURBANCHAL UNIVERSITY : 2081 B.E, (Civil)/Sixth Semester/Final : . | Time: 03:00 hrs. Full Marks: 80 /Pass Marks: 32 BEG359CI: Foundation Engineering Candidates are required to give their answers in their own words as far as practicable. All questions carry equal marks. Thé marks allotted for each sub-question is specified along its ‘side..Assume. suitable data if necessary. Answer FIVE ‘questions. l(a) Explain how standard, penetration test is carried out in the field. What various corrections are made on the tested value?. Describe the nature of sample obtained from the test. 44341 (b) Determine the maximum and minimum pressure under the base of the cantilever retaining wall as shown in figure and also, the” factor of safety against sliding-and overturning, The appropriate - shedr strength parameters for soil, are'c =-0;" = 40°, The unit’ weight of soil. and’ concrete, are 18KN/m? and 24KN/m* respectively. Take 6 = 3st 445m 2a) What are the basic differences between ‘Coulomb and ‘Rankine’s earth pressure theories? Derive the expression of active a " pressure using Rankine’s theory for (c, 4) soils. contd. wee Scanned with CamScanner] 3{a) What are the various types of loads that are considered ' +“ of foundation? Discuss the procedure for proportioning of footing ay \| 5 {b) A footing of 1.5m diameter carries a load of 800KN. The soil (c= 0) has an angle of internal friction of 36° and unit weight of 18KN/m?. What will be the depth of foundation, if factor of safety is 2.5, for $369, Ny = 38 and N; = 41, Pott oe for uniform settlement. F 8 (bo) What are the conditions for the suitability of mat foundation? Also descrike the design procedure of the mat foundation. 8 4(a) What. are the functions ‘of various components .of well ' foundation? How well foundation is sunk? (b). A concrete pile 30cm diameter is driven into a medium dense sand Y2A$ ($350, ¥-21 KN/m%, K=1.0,.tan§ = 0.70) for a depth of 8m. If the <2) water table is 2m below the ground surface, estimate the safe load taking a factor of safety of 2.5. : Th 8 5(a) Define negative’ skin friction. Describe how the negative skin (0 friction in single and pile groups can be calculated? What are the - methods of reducing skin friction? 24442 A 4m deep: excavation ‘of a trench is carried out in sand and supported by cantilever’ sheet pile wall. The water table at both sides of the sheet pile wall is found at the bottom of the excayation. The bulk unit weight of the sand is 20 KN/m3 above the Water table ‘and 22KN/m' below the water: table. The angle of internal friction of sand both below and above the water table is 30°, Determine the required depth of embedment by using simplified method. . 7. “8 6(a) What are the various methods’ of removing ground water from contribution ‘sites? Describe three prominent methods offoundation soil stabilization. *2+6=8 (b). Calculate the: active lateral force and the line. of action’ of the force from the base of the wall on a retaining wall Sm, high. The position of the ground water table is 2m.below from the top of the wall, Take the unit weight, undrained cohesion and angle of shearing resistance of the soil’ above (18KN/m’, 10KN/m?, 20°) and’ below (221KN/m*, +, OKN/m?, 309) the water table respectively. The backfill surface is * sloping at an angle of 15° with horizontal. 8 Scanned with CamScanneri BE, (Civil)/Sixth Semester/ Final Time: 03;00 hrs. Full Marks: 80/Pass Marks: 3 PURBANCHAL UNIVERSITY ; ae 2010 BE. (Civil)/Sixth Semester/ Final : Time: 03:00 hrs. s Pull Marks: 80 /Pass Marks: 32 BEG3S9CI: Foundation Engineering Candidates are required to give their answers in their own words as far @s practicable, | All questions carry equal marks. The marks allotted foreach sub-question ° 1s specified along its side. Assume suitable data ifnecessary. * “Answer FIVE questions. 1a), What are the objectives of site investigation? Describe the method of standard penetration test. : 345 (b) A retaining wall of 6.0m high has two layers of backfill. The soil supported consists ‘of 3.5m thick sand (17.5 KN/m3, $=30°) overlying saturated sandy clay (y=19.25 KN/m%, Ser c=16.6KN/m?). The ground water table is at the upper surface of the sandy clay. Make a sketch of the distribution of the active pressure on the wall. Calculate the point of application of lateral thrust. 8 2(a) What are the essential parts of site investigation report? Describe 7 the bore hole log with typical example. 345 o The top of the masonry retaining wall is 0.Sm, ‘bottom is 4.0m and height of the wall is 5.0m. Check the stability of the wall against sliding, overturning and bearing if the unit, weight of masonry is: 24KN/m®, allowable bearing pressure’ of soil is 500KN/m? and the coefficient of base friction is 0.6. Assume that the water table is at 3.0m from the base of the wall. 8 ‘20KNim* ted i | AG RN/a? | . i $230" e=0 yori boa EA. | Fig. 2(0) ' Contd. ... 25m Nat osm Scanned with CamScanner3(a) Describe the Culmann’s graphical method ‘for active ¢: *( arth’ 8 ‘pressure analysis. , enh 168 The rectangular footing of size 1mx2m is placed at a depth 1. ") ee ee level, Calcitate safe bearing capacity of soil ire. factor of safety 3.0, using Skempton’s method and Terzaghi’s noel + ‘The unit weight of soil above water table is 17KN, [/m3 and below water table is 19 KN/m3, cohesion 20 KN/m? and internal friction is zero. The water.table is located at 2.0m below the ground level, 8 4{a) Describe pile load test, How bearing capacity is determined by pile load test? ad 8 () “A concrete pile of 35 cm diameter is driven into a medium dense sand (=23.5 KN/m3, K=1.0,:tan5=0.771) for a depth of 8m. If water table is 2.5m below the ground surface, determine the safe load that can take hy the pile for factor of safety 2.50. Take 7479.81 KN/mé. 8 51) What is'negative skin friction? What is its effect on the pile? 8 ge(b) The plan of a tat foundation with 9 columns is: shown in Fig, 5(b). below. Assuming: that the-mat is rigid, determine the soil pressure distribution at four corners of the mat. All the columns are of the size 0.6mx0.6m, 8 fy " Fig. 5(b) Contd... ° Scanned with CamScanner| a) | “3 Sta). Describe the component parts of a well foundation with neat sketch, : (b) A group of 16 Piles "(giameter=S0em, length=14m, centre to centre spacing=1m}' are arranged in a square! pattern passing through a recent {ill of thickness of 3m overlying a soft clay deposit of thickness 5m-which is consolidating under the fill load and rests on a stiff clay strata. All the strata are saturated. The soil properties of different strata are as follows in the table. Unit welght | Strength parameters | Adhesion Type ot soll kn?) [ay (kina [_@ | factor (a) Fi 16 50 0 of 0.60 Soft clay 17, 20 0.40 sifiday [21 70 0 [04s ; Estimate the ultimate load carrying capacity ‘of (Qu) of the pile group. . : ! 8 | ' | | | | i| . a Scanned with CamScannerMu anaias, OU/ Fass MArKS! 6% 1 - PURBANCHAL UNIVERSITY : . 2009 . B.E. (Civil) /Sixth Semester/Chance . ' Time: 03:00 hrs, Full Marks: 80 /Pass Marks: 32 BEGSS9CI: Foundation Engineering - Candidates are re : quired to give their answers in their own words as far 5 as practicable, All questions carry equal marks, The marks allotted for each sub-question 1S specified along its side. Assume Suitable data if necessary. “Answer FIVE questions., la]. What do you understand by site investigation? What are the different purposes for which site investigations are done? What are disturbed and undisturbed samples? 8 (b) What is a gravity retaining wall? Sketch a gravity retaining wall showing the lateral pressure distribution ‘and explain all types of stability checks that have to be done. 8 2{a) Briefly discuss at rest, active and passive earth pressures on a retaining wall. Describe Culmann's method for the determination of active earth pressure. 8 (b) A rectangular footing 1.5mxim is shown in the Fig. 2(b). Determine the magnitude of the gross ultimate Joad applied eccentrically, for the bearing capacity failure in soil. Ny and N, for " $'=320 are 18.5 and 15.8 respectively. 8 ty ye 19 Nie? b=32 ceo Fig. 2(b) Contd. ... Scanned with CamScanner3f{a) (b} 4(a) {b) (2) Categorize different types of shallow foundations, Explain the procedure for the design of a spread footing, : a For the mat shown in the Fig, 2(b), Qs, Qs" 40 tons, Qs, Qs, Qc=60stons, Qo, Qo=45 tons, and Qz, Qs=50 tons, All columns are of size 9 in.x9 in. in cross section. Determine the pressure on the soi] under the columns A,B, C, D, E, F, Gand H, g& y . Fig, 3(b) Describe the pile types on-the ‘basis of mechanism of load transfer: What is pile capacity? Discuss negative skin friction, 8 Determine the depth of embedment for the cantilever sheet pile shown.in the Fig, 4(b); : “¢ = 50 kNiin? Fig. 4(b) Contd. ... Scanned with CamScanner(3). 5(a) A‘concrete:pile, 30cm diameter, ‘is me into a medium dense (b) 6(a) (b) Q) * the water table is 2m below the ground surface, sand (#'=35°, y=21kN/m3, K=1.0, tand=0.70) fo a depth of 8m, Ir lestimate the safe load taking a factor of safety of 2.50, Take Yw= 1OKN/m, 8 Describe various methods for the a of drilled piers. 8 Write down Terzaghi's general bearing capatity equation with the assumptions and explain all bearing capacity factors with their expressions. | | 4 8 For the retaining wall shown in Fig. 6(b), assume that the wall can yield sufficiently to develop active state. Determine Rankine active force per unit length of the wall and the location of the Tesultarit line of action, 8 s . kNim? te . am $23 Scanned with CamScanner