RRB JE Civil 19 September 2019 PDF Exam Paper

 (a) Dry silica sand (b) Foundry sand RRB JE Civil Paper (c) Wet clay (d) Coal run of mine 19 September 2019...

 (a) Dry silica sand (b) Foundry sand RRB JE Civil Paper (c) Wet clay (d) Coal run of mine 19 September 2019 Ans. (b) The permissible incline in a belt conveyor is the maximum angle at which the conveyor can operate Q.01. Which of the following apparatus is used to without the material sliding back down the belt. The determine the specific gravity of the soil? angle of incline depends on several factors, including (a) Penetrometer (b) Tachometer the type of material being conveyed, the belt speed, (c) Pycnometer (d) Graphometer and the surface characteristics of the belt. Ans. (c) Pycnometer method : is used to determine Dry silica sand has a high angle of repose, which specific gravity and water content both. This method is means that it can be conveyed at a steeper angle suitable for cohesionless soils. without sliding back. However, foundry sand is more Pycnometer is a glass jar of 1-liter capacity that is fitted cohesive and has a lower angle of repose. This means at its top by a conical cap made of brass. It has a screw that it is more likely to slide back down the belt if the type cover and there is a small hole at its apex of 6 mm incline is too steep. diameter. Wet clay has a very low angle of repose and is difficult to convey on a belt conveyor. It is often necessary to use a screw conveyor or other type of conveyor for wet clay. Coal run of mine has a moderate angle of repose and can be conveyed on a belt conveyor at a relatively steep angle. However, it is important to ensure that the belt speed is not too high, as this can cause the coal to slide back down the belt. Therefore, the permissible incline in a belt conveyor W1 = Mass of empty volume of pycnometer will be maximum for foundry sand, which has a lower W2 = Mass of pycnometer + Mass of moist sample angle of repose and is less likely to slide back down n tio W3 = Mass of pycnometer + soil + water the belt. nc Q.04. In which method of disposal of municipal solid Ju W4 = Mass of pycnometer full of water il Gs = Specific gravity of soil solids waste, the waste is dumped in the soil? iv C Water content of the soil sample is given by: (a) Incineration (b) Land filing 𝑾𝟐 −𝑾𝟏 𝑮−𝟏 (c) Composting (d) Shredding 𝒘=( )( )−𝟏 𝑾𝟑 −𝑾𝟒 𝑮 Ans. (b) Landfilling : Landfilling is a method of waste Specific gravity is usually reported at 27°C and it is given disposal in which waste is buried in the ground in a by: specially designed and engineered facility called a 𝑾𝟐 −𝑾𝟏 𝑮𝒔 = (𝑾 landfill. 𝟐 −𝑾𝟏 )−(𝑾𝟑 −𝑾𝟒 ) Landfills are typically located in remote areas to Q.02. What is the permissible tensile stress in bolts minimize the impact on surrounding communities. used for column bases? The waste is compacted and covered with soil to (a) 120 N/mm2 (c) 150 N/mm2 prevent it from being exposed to the environment. 2 (c) 0.4 N/mm (d) 0.6 N/mm2 Landfills are also designed to collect and manage the leachate and gases produced by the decomposition of Ans. (a) Permissible tensile stresses in bolts used for waste. This helps to protect groundwater and air column bases is 120 N/mm2. quality. Permissible Maximum Stress Stress Value Q.05. What is a 'Coping'? Permissible average shear stress 0.40 fy (a) Ornamental moulded course placed on the top of Permissible maximum shear stress 0.45 fy wall (b) A projecting piece usually provided to support a Permissible axial tensile stress 0.60 fy truss Permissible compressive or tensile 0.66 fy (c) A projecting piece usually provided to support a bending Stress roof Permissible bearing stress 0.75 fy (d) A covering of concrete placed on the exposed top of Q.03. In which case will the permissible incline in belt an external wall conveyor be maximum? RRB JE Civil 19 September 2019 1 Civil KI Goli Ans. (d) Coping: It is a course placed upon the exposed (c) 45° (d) 10° top of an external wall to prevent the seepage of water. Ans. (a) Web Crippling : It occurs due to a concentrated Various components of the building are given in below load on the beam, due to reaction at support, high figure : compressive stresses are produced in the web near to the upper flange or lower flange. Web crippling result in stress concentration and bearing failure. If the beam section is safe in crippling, it will also safe in buckling. Load dispersion angle from bearing plate -30o Q.08. The area covered by all floors of the building is called- (a) Floor area (b) Built up area (c) Floor space index (d) Carpet area Ans. (b) Plinth area : It is the covered built- up area measured at the floor level of any storey or at the floor level of the basement. The plinth area is also called a built-up area and is the entire area occupied by the building including internal and external walls. It is generally 10-20% more than the carpet area. Q.09. The point where the alignment changes from a straight line or tangent to a circular curve is called as- (a) Point of commencement (b) Point of curvature (c) Point of tangency Q.06. Bench mark is established by - (d) Finishing mark (a) Spirit levelling Ans. (b) (b) Hypsometric levelling (c) Barometric levelling Term Definition (d) Trigonometrical levelling Back Tangent (First The tangent line preceding the Ans. (a) A benchmark is a point of reference by which Tangent) curve. something can be measured. In surveying. Forward Tangent The tangent line following the A "benchmark" is a post or other permanent mark (Second Tangent) curve. established at a known elevation that is used as the basis for measuring the elevation of other Point of The point where the back tangent topographical points. Intersection (PI) and forward tangent intersect. Benchmark is established by spirit levelling in which it consists of a telescope with a crosshair and a tube level Point of Curve (PC) The beginning point of the curve or bubble level used to indicate whether a surface is where the alignment changes horizontal. from straight to curved. Q.07. In case of web crippling, the dispersion of load Point of Tangency The ending point of the curve from bearing plate takes place at: (PT) where the alignment changes (a) 30° (b) 60° from curved to straight. RRB JE Civil 19 September 2019 2 Civil KI Goli  Average Size of Type of soil Permeability (k) Particles 80 mm - 4.75 Gravel > 1 cm/sec mm 4.75 mm - Sand 1-10-3 cm/sec 0.075 mm 0.075 mm - Silt 10-3 -10-7 cm/sec 0.002 mm Clay < 0.002 mm < 10-7 cm/sec T1 = Point of curve or point of commencement (or) Q.12. A longitudinal crack which is usually normal to Tangent point the annual rings in wood is called- T2 = End of the curve (or) point of tangency (a) Star shakes (b) Heart shakes B = Point of intersection (c) Cup shakes (d) Checks T1FT2 = Length of a curve Ans. (d) Various forms of defects in timber due to OF = Radius of curve Abnormal growth or rupture of tissues due to natural T1T2 = Length of the long chord forces are as follows : Q.10. An increase in load at the free end of a cantilever Checks : It is a longitudinal crack which is usually is likely to cause failure- normal to the annual rings. These adversely affect the (a) At the free end durability of timber because they readily admit (b) Anywhere in the beam moisture and air. (c) At the mid of its length Shakes : These are longitudinal separations in the wood between the annual rings. These lengthwise (d) At the fixed support end separations reduce the allowable shear strength Ans. (d) A cantilever beam subjected to point load on without much effect on compressive and tensile values. free end will have a maximum bending moment at the The separations make the wood undesirable when n fixed end and constant shear force throughout the appearance is important. tio nc length. Both the shakes and checks if present near the Ju So maximum stress will be at the fixed end (σ=My/I) neutral plane of a beam they may materially weaken il iv and failure will occur at that point. its resistance to horizontal shear. C Maximum Bending moment will occur at a fixed end. Heart Shake : These occurs due to shrinkage of heart Mmax = -WL wood, when tree is overmatured. Cracks start from pith ∴ A beam is loaded as a cantilever. If the load at the end and run towards sap wood. These are wider at center is increased, the failure will occur at the support. and diminish outwards. Cup Shake appears as curved split which partly or wholly separates annual rings from one another. It is caused due to excessive frost action on the sap Q.11. The coefficient of permeability of gravel is- present in the tree, especially when the tree is young. (a) Less than 10–6 cm/sec Star Shake : These are radial splits or cracks wide at (b) Between 1 and 100 cm/sec circumference and diminishing towards the center of (c) Between 1 × 10–6 and 1 × 10–3 cm/sec the tree. This defect may arise from severe frost and (d) Between 0.001 and 1 cm/sec fierce heat of sun. Star shakes appear as the wood dries Ans. (b) Permeability (k) of soil depends on the average below the fiber saturation point. It is a serious fault size of the pores and is related to the distribution of leading to separated log when sawn. particle sizes, particle shape, and soil structure. Shakes are most harmful to strength when they Different type of soil and their standard permeability follow neutral plane of a beam or run diagonally rate : across the tension side of it. In the first case, they RRB JE Civil 19 September 2019 3 Civil KI Goli  weaken the resistance to horizontal shear, and in the the bed. They are cleaned by backwashing water second, they reduce the tensile strength. through the bed to 'lift out' the particles. Rind gall : It is characterized by swelling caused by the Cleaning : growth of layers of sapwood over wounds after the Cleaning of filter can also be done using surface wash branch has been cut off in an irregular manner. The but it should be accompanied by back wash. newly developed layers do not unite properly with the Washing period = 24 to 48 hrs. old rot, thereby leaving cavities, from where decay Q.15. The significant property of CPVC, which differs it starts. from PVC is- Knots are bases of twigs or branches buried by cambial (a) Improved heat resistance activity of the mother branch. The root of the branch is (b) Higher scrap value embedded in the stem, with the formation of annual (c) Heavy weight rings at right angles to those of the stem. The knots (d) Decreased heat resistance interrupt the basic grain direction of the wood, resulting in a reduction of its strength. Ans. (a) The significant property of CPVC, which differs A dead knot can be separated from the body of the it from PVC, is improved heat resistance. wood, whereas live knot cannot be separated. Knots CPVC (chlorinated polyvinyl chloride) is a type of PVC reduce the strength of the timber and affect that has been modified to have a higher chlorine workability and cleavability as fibers get curved. Knots content. This gives CPVC a higher heat resistance than are classified on the basis of size, form, quality and PVC. CPVC can withstand temperatures up to 200 occurrence. degrees Fahrenheit, while PVC can only withstand temperatures up to 140 degrees Fahrenheit. Q.13. Mortar or concrete conveyed through pressure hose and applied pneumatically at high velocity on PVC has a higher scrap value than CPVC because it is structural surfaces is called- more common and easier to recycle. PVC is also heavier than CPVC because it has a higher density. (a) Sealing (b) Grouting (c) Guniting (d) Spraying Q.16. The point within the cross sectional plane of a beam, through which the resultant of the external Ans. (c) Shotcrete or Gunite : Shotcrete or Gunite is loading on the beam has to pass through to ensure pure mortar or concrete conveyed through a pressure hose bending without twisting of the cross section of the and applied pneumatically at high velocity onto a beam is called as- surface. (a) Elastic centre (b) Moment centre This material has found wide applications in several (c) Shear centre (d) Centroid major repair works as it can be applied on vertical, horizontal, or overhead surfaces, with the area to be Ans. (c) Shear centre : Shear centre is a point from repaired being either reinforced or unreinforced. which a concentrated load passes then there will be only bending and no twisting. Q.14. The period of cleaning of a slow sand filter, is usually- It is also called centre of twist. (a) 5 to 10 days It is that point through which the resultant of shear (b) Three months to six months passes. (c) One month to three months To avoid twisting and only cause bending, it is (d) Two weeks to three weeks necessary for the forces to act through a particular point, which may not coincide with the centroid. Ans. (c) Slow sand filter : They consist of fine sand, supported by gravel. They capture particles near the Q.17. In AutoCAD, a cylinder can be created by drawing surface of the bed and are usually cleaned by scraping a rectangular shape using _________ tool. away the top layer of sand that contains the particles. (a) Extrude (b) Polysolid Cleaning : (c) Revolve (d) Sweep For cleaning, the top layer of sand is scrapped and 1.5 Ans. (c) To create a cylinder in AutoCAD using the to 3 cm of sand is removed in each cleaning. Revolve command, follow these steps : The frequency of cleaning is 1 to 3 months. Draw a rectangular shape using the Rectangle Rate of filtration is 100-200 l/hr/m2 of filter area. command. Select the rectangle and click on the Revolve It is used for smaller plants in villages. command from the 3D Modeling panel. Rapid sand Filter : They consist of larger sand grains Specify the axis of revolution by clicking on two supported by gravel and capture particles throughout points on the drawing. RRB JE Civil 19 September 2019 4 Civil KI Goli  Specify the angle of revolution by entering a value in Ans. (a) Normal Consistency test : - The Normal the Angle of revolution field. consistency or standard consistency of a cement paste Click on the OK button to create the cylinder. is defined as that consistency which will permit the Q.18. The bearing capacity factors Nc, Nq and Nr are vicat plunger to penetrate to a point 5 to 7 mm from the function of- bottom of the vicat mould. (or 33-35 mm from top of vicat mould). (a) Width and depth of footing (b) Angle of internal friction of soil For finding out initial setting time, final setting (c) Density of soil time, soundness of cement and compressive strength (d) Cohesion of soil of cement, it is necessary to fix the quantity of water to be mixed in cement in each case. Ans. (b) Bearing capacity factors : Terzaghi's bearing capacity factors - Nc, Nq, Nγ depend on the angle of internal friction only and are dimensionless. Where Nq = Nϕ × eπ.tanϕ 𝛟 𝐍𝛟 = 𝐭𝐚𝐧𝟐 (𝟒𝟓𝒐 + ) = 𝐢𝐧𝐟𝐥𝐮𝐞𝐧𝐜𝐞 𝐟𝐚𝐜𝐭𝐨𝐫 𝟐 𝐍𝛄 = 𝟏. 𝟖 𝐭𝐚𝒏 𝛟 (𝐍𝐪 − 𝟏) [𝐍𝐜 = 𝐜𝐨𝐭 𝛟 (𝐍𝐪 − 𝟏)] Q.19. In case concrete is to be transported by pumping, the slump of the concrete should be- (a) More than 1 cm (b) Between 5 to 7.5 cm (c) More than 2.5 cm (d) Between 2.5 to 5 cm Ans. (b) Slump test : The slump test is the most n tio commonly used method of measuring the consistency nc For initial and final setting time test water required is Ju of concrete which can be employed either in the il laboratory or at the field. 0.85 times that required for normal consistency. iv C Slump value is the amount (depth) by which the Q.21. Eutrophication of water bodies is caused by the- concrete settles down after removing the slump cone. (a) Excessive discharge of suspended solids (b) Excessive discharge of nutrients Placing condition Degree of Slump (c) Excessive discharge of chlorides workability (mm) (d) Discharge of toxic substance Blinding concrete; Shallow Very low - Ans. (b) Eutrophication is an accelerated growth of sections; Pavements using algae on higher forms of plant life caused by the pavers enrichment of water by nutrients, especially Mass concrete; Lightly low 25-75 compounds of nitrogen and phosphorous. reinforced sections in slabs, It induce an undesirable disturbance to the balance of beams, walls, columns; Floors; organisms present in the water and to the quality of Hand placed pavements; water concerned. Canallining; Strip footings Heavily reinforced sections in Medium 50- The main cause of eutrophication is the large input of slabs, beams, walls, columns; 100 nutrients to a water body and the main effect is the Slipform work; Pumped 75- imbalance in the food web that results in high levels of concrete 100 phytoplankton biomass in stratified water bodies. This Trench fill; In-situ piling High 100- can lead to algal blooms. 150 Q.22. The purpose of a Well Point System is- Tremie concrete Very high - (a) Desilting Q.20. In Vicat apparatus, the paste is said to be of (b) Dewatering 'Normal consistency' if the rod penetrates- (c) Resisting Soil Pressures (a) 33 to 35 mm (b) 23 to 25 mm (d) Forming underwater foundation (c) 5 to 10 mm (d) 1 mm RRB JE Civil 19 September 2019 5 Civil KI Goli Ans. (b) The purpose of a Well Point System is Ans. (b) Capital Cost : Capital cost refers to the total cost dewatering. incurred from the beginning to the completion of a A well point system is a system of wells that is used construction project. It includes all expenditures to lower the water table in the ground. related to the project, from planning and design to This can be done for a variety of reasons, such as to : construction and finishing. Other Type of cost : - Prepare a construction site for excavation Approximate cost: Repair or replace underground utilities Labor cost: Stabilize a slope Material cost: Dewater a flooded area Q.26. If the particles of a fluid attain such velocities that Well point systems typically consist of a series of vary from point to point in magnitude and direction as small-diameter wells that are installed around the well as from instant to instant, the flow is said to be- perimeter of the area to be dewatered. The wells (a) Uniform flow (b) Laminar flow are connected to a pump, which removes water from the wells and lowers the water table. (c) Non-uniform flow (d) Turbulent flow Desilting is the process of removing silt from water. Ans. (d) In fluid dynamics, turbulent flow is Resisting soil pressures is the ability of a structure characterized by the irregular movement of particles of to withstand the forces exerted by the soil. the fluid. In contrast to laminar flow the fluid does not Forming underwater foundation is the process of flow in parallel layers, the lateral mixing is very high, constructing a foundation underwater. and there is a disruption between the layers. In Q.23. ___________ is the collective term for the turbulent flow the speed of the fluid at a point is physical manifestations of the defects like cracks, continuously undergoing changes in both magnitude spalling, pop out, staining and corrosion. and direction. (a) Preservation (b) Distress (c) Defects (d) Failure Ans. (b) Distress:- It is a collective term for the physical manifestation of problems such as cracks, spalls, pop- outs, staining, decay or corrosion. Distress can be thought of as the symptoms indicating that the defects are present. Q.27. In which type of plan is space left around the construction of the building? Q.24. A railway yard in which wagons are received, sorted and new goods trains are formed is called - (a) Landscape plan (b) Line plan (a) Shunting yard (b) Marshalling yard (c) Detailed plan (d) Foundation plan (c) Station yard (d) Goods yard Ans. (a) Landscape plan : In a landscape plan, space is Ans. (b) Marshalling : Marshalling Yard is a place where left around the construction of the building. goods trains are received, sorted, reformed and A landscape plan is a plan that shows the dispatched. arrangement of natural and man-made features on a This yard is provided with distributing machine with piece of land. facilities for receiving, sorting and dispatching It typically includes the location of trees, shrubs, wagons to their various destinations onwards. flowers, walkways, patios, and other features. Marshalling yard has a network of tracks, divided into Type of Plan : - several grids for receiving, sorting, forming and Line plans → are simple plans that show the outline of dispatching of trains. a building or other structure. Types of Marshalling Yards : Detailed plans → are more detailed than line plans and 1. Flat Yards show the layout of the building, including the location 2. Hump yard of rooms, doors, and windows. 3. Gravity Yards Foundation plans → show the layout of the foundation Q.25. The cost of construction including all the of a building. expenditure incurred from beginning to the completion Q.28. The temporary all round enclosure which keeps of work is called as- the water away from the working area by using vertical (a) Approximate cost (b) Capital cost barriers is called- (c) Labour cost (d) Material cost (a) Arch dam (b) Gravity dam RRB JE Civil 19 September 2019 6 Civil KI Goli (c) Coffer dam (d) Earthen dam the magnetic north is to the east of the true north, Ans. (c) Coffer Dam : A coffer dam is a temporary all- the declination is said to be east or positive. round enclosure constructed to keep water away from a working area, allowing construction or repair work to Q.30. The strength of compression members subjected be carried out in dry conditions. It is typically used in to axial compression is defined by curves water-filled environments, such as rivers, lakes, or corresponding to _______ classes. coastal areas. (a) e, f, g (b) b, e, f Type Of Dams : (c) a, b, c and d (d) a, d Arch dam : An arch dam is a curved structure that relies Ans. (c) IS 800: 2007 gives buckling curves a, b. c, d in on the arch action to transfer the water load to the non-dimensional form for different cross-sections of abutments (side supports) of the dam. columns. Arch dams are typically constructed in narrow valleys Curve 'a' represents quasi-perfect shapes such as hot with steep sides. rolled I section if buckling is perpendicular to the Gravity dam: A gravity dam is a massive structure that major axis relies on its own weight to resist the water load. Curve 'b' represents shapes with medium Gravity dams are typically constructed of concrete or imperfections, it defines the behavior of rolled I masonry. sections buckling about the minor axis, welded I Earthen dam: An earthen dam is a structure sections of thin flanges, and of rolled I sections with constructed from compacted soil, rock, or other natural medium flanges if buckling is about the major axis; materials. and most welded box sections. Earthen dams are commonly used for water storage, Curve 'c' represents a lot of imperfections such as flood control, and irrigation purposes. channels, angles, Tee Shaped sections, thick welded box sections, hot rolled sections rolled about the Q.29. The smaller horizontal angle between the true minor axis, I sections buckling about the major axis. meridian and a survey line, is known as- Curve 'd' represents shapes with maximum (a) True bearing (b) Arbitrary meridian n imperfections. It is to be used for hot-rolled I sections tio (c) Azimuth (d) Magnetic bearing nc with very thick flangs and welded I sections if Ju Ans. (c) Azimuth : The horizontal angle made by a true buckling occurs about a minor axis. il Table 10 of IS 800:2007 shows the 'buckling class of iv meridian with the survey line is called as azimuth. C Azimuths are generally observed from north. Azimuths Cross-sections" along with their uses. may be geodetic, astronomic, magnetic, grid, record, or For Built-up Member Buckling Class C is used. assumed, depending on the reference meridian used Magnetic bearing : Magnetic bearing of a line is the horizontal angle which the line makes with the magnetic north. It changes with time. It is used for small areas and it is measured with the magnetic compass. Dip : It is the inclination of the magnetic needle with the horizontal. The dip is zero at the equator and the needle will remain horizontal. At a place near 70° north latitude and 96° west longitude, the dip will be 90°. This area is called the magnetic north pole. Similarly, near the south magnetic pole, the dip is 90°. Magnetic declination : The magnetic declination and the true meridian at a place generally do not coincide. The horizontal angle which the magnetic meridian makes with the true meridian is called the magnetic declination. If the magnetic north is to the west of the true north, the declination is said to be west or negative and if RRB JE Civil 19 September 2019 7 Civil KI Goli Q.31. Quadrennial repair is done in- Ans. (b) Compressed air method : The essential (a) Twice a year (b) Four times a year principle of this method is the use of compressed air (c) Alternate year (d) Once in four years and is very well suited for soft or water-bearing ground. Ans. (d) Quadrennial repair is done once in four years. It consists of forcing air under suitable pressure into The word "quadrennial" means "occurring once every an enclosed space like tunnel heading, to force back four years". percolating water or water mixed soil and thus stabilize the area of excavation. Semi-annual: Occurring twice a year. Method of tunneling in hard rocks - Annual: Occurring once a year. Biennial: Occurring once every two years. Full face method Heading and bench method Q.32. Full architectural and structural drawings are Pilot tunnel method required for which type of estimate? Perimeter method of tunneling (a) Detailed estimate Drift method (b) Functional unit estimate Method of tunneling in running ground (c) Rough or preliminary estimate (d) Supplementary estimate Forepoling method Linear plate method Ans. (a) Full architectural and structural drawings are Needle beam method required for a detailed estimate : A detailed estimate American method is a comprehensive estimate of the cost of a English method construction project. It is based on a detailed analysis Austrian method of the project drawings and specifications. Detailed Belgian method estimates are typically used for bidding purposes and for cost control during construction Flying arch Functional unit estimate : An estimate based on the Q.35. Plaster of Paris is obtained from the calcination unit cost of similar projects. of- Rough or preliminary estimate : An estimate based on (a) Bauxite (b) Dolomite the estimated cost of major components of the project, (c) Gypsum (d) Lime stone such as the cost of materials and labor. Ans. (c) Calcination or calcining is a thermal treatment Supplementary estimate : An estimate of the cost of process to bring about a thermal decomposition. The changes to a project after the original estimate has process takes place below the melting point of the been prepared. product. The name calcination is derived from the Latin Q.33. Floating foundation means- word ‘Calcinare’ which mean to burn lime. 𝐡𝐞𝐚𝐭 (a) A normal foundation which can raise and float 𝐂𝐚𝐂𝐎𝟑 → 𝐂𝐚𝟎 + 𝐂𝐎𝟐 (𝐋𝐢𝐦𝐞𝐬𝐭𝐨𝐧𝐞) → (𝐋𝐢𝐦𝐞) + during floods (𝐂𝐚𝐫𝐛𝐨𝐧𝐝𝐢𝐨𝐱𝐢𝐝𝐞) (b) A foundation floating on water like barges Calcination of Limestone results in Lime and of bauxite (c) A foundation in which new loads due to the results in Alumina. structure are equal to the weight of the soil ✓ The gypsum so obtained is added while cement removed by excavation manufacturing to prevent its flash setting. (d) A foundation cannot be floating type under any Q.36. If a body is acted upon by a set of mutually condition perpendicular shear stresses, the diagonal planes are Ans. (c) A floating foundation is a type of foundation in likely to have- which the new loads introduced by the structure are (a) Tension only approximately equal to the weight of the soil excavated (b) Compression only during the construction of the foundation. In other words, the foundation neither settles nor exerts (c) Tension and Compression significant pressure on the underlying soil. (d) No tension or compression Q.34. Which of these methods of tunnel construction is Ans. (c) If a body is acted upon by a set of mutually not suitable in rocks? perpendicular shear stresses, the diagonal planes are (a) Drift method likely to have both tension and compression. This is (b) Compressed air method because shear stresses cause the body to deform in a (c) Heading and benching method way that creates both tensile and compressive stresses (d) Full face method on the diagonal planes. RRB JE Civil 19 September 2019 8 Civil KI Goli To understand why this happens, consider a (d) Both ends fixed rectangular block of material subjected to shear Ans. (a) A column with maximum equivalent length has stresses on two opposite faces. The shear stresses one end fixed and the other end is free. cause the block to deform in a way that it becomes Effective parallelogram-shaped. This deformation creates tensile Support Condition Length stresses on the diagonal planes that are oriented in the Both ends hinged Le=L direction of the shear stresses, and compressive 𝑳 stresses on the diagonal planes that are oriented Both ends fixed Le= 𝟐 perpendicular to the shear stresses. 𝑳 One end is fixed other end hinged Le= √𝟐 The following diagram shows the stress distribution on One end is fixed other end free Le=2L the diagonal planes of the block : Q.39. The ratio of the inertia and viscous forces acting in any flow, ignoring other forces is called as (a) Froude number (b) Reynold number (c) Weber number (d) Euler number Ans. (b) Forces encountered in flowing fluids include those due to inertia, viscosity, pressure, gravity, surface tension and compressibility. These forces can be written as follows : Reynolds number (Re) : It is defined as the ratio of inertia force to viscous force. The magnitude of the tensile and compressive Re= ρVl μ stresses on the diagonal planes depends on the magnitude of the shear stresses and the material Froude number (Fr): properties of the block. In general, the higher the It is defined as the ratio of inertia force to gravity force. V shear stresses, the greater the tensile and Fr = n tio √gL compressive stresses on the diagonal planes. nc It is important to note that the tensile and Weber number (We): Ju It is defined as the ratio of the inertia force to surface il compressive stresses on the diagonal planes are not iv C always equal in magnitude. This is because the tension force. material properties of the block may be different in ρV 2 l We= different directions. For example, a material may be σ stronger in tension than in compression, or vice versa. Mach number (M): It is defined as the ratio of inertia force to velocity of Q.37. By which of the following lines is the axis of the sound. cylinder or sphere denoted? V V (a) Leader line (b) Section line M= = c dP √ dρ (c) Hidden line (d) Centre line Ans. (d) The axis of a cylinder or sphere is denoted by a Q.40. Which type of surface finishing in Brick Masonry centre line. / Block Masonry / Stone Masonry treats only the joints edges and not the full wall surface? A centre line is a line that passes through the center of a circular or cylindrical object. It is used to indicate the (a) Plastering (b) False ceiling symmetry of the object and to show the direction of (c) Grouting (d) Pointing the axis of rotation. Ans. (d) Pointing : Leader lines are used to connect a note or dimension to It is a type of surface finishing in brick masonry, block a feature on a drawing. masonry, and stone masonry that treats only the Section lines are used to indicate where a section view joints edges and not the full wall surface. is taken. It involves applying a mortar mix to the joints Hidden lines are used to represent features of an object between the masonry units to create a smooth and that are not visible from the current viewing direction. uniform appearance. Q.38. A column with highest equivalent length has- Pointing can also help to protect the joints from (a) One end fixed, the other entirely free moisture and weathering. (b) Both ends hinged or pin-joined (c) One end fixed, the other end hinged RRB JE Civil 19 September 2019 9 Civil KI Goli Plastering : Plastering is the application of a mixture of Biochemical Oxygen Demand (BOD) : A measure of the sand, cement, and water to a wall surface to create a amount of oxygen required by microorganisms to smooth and even finish. decompose organic matter in water. False ceiling : A false ceiling is a secondary ceiling that Most Probable Number (MPN) : A method for is suspended below the main ceiling. It is typically used estimating the number of coliform bacteria in water. to conceal unsightly pipes and wires, or to improve the Dissolved Oxygen (DO) : A measure of the amount of acoustics of a room. oxygen dissolved in water. Grouting : Grouting is the filling of gaps or voids in DO is a rapid test that can be used to indicate the masonry joints with a mortar mix. It is often used to intensity of pollution of water. It is a simple and strengthen and stabilize masonry structures. inexpensive test that can be performed in the field. Q.41. To avoid vapourisation, pipe lines are laid over the ridge so that they are not more than _________ Q.43. The shape factor for a solid circular section of above the hydraulic gradient line. diameter D is equal to: (a) 6.4 m (b) 2.4 m (a) D/2π (b) 16/3π (c) 5 m (d) 10 m (c) πD/8 (d) 15/2π Ans. (a) Hydraulic Gradient Line (H.G.L) : It is defined as Ans. (b) the line which gives the sum of pressure head (P/ρg) and datum (z). 𝑷 𝑯. 𝑮. 𝑳 = +𝒛 𝝆𝒈 ∴ H.G.L line lies below T.E.L with a difference of Velocity head (V2/2g). In order to avoid vaporization in the pipeline, the pipeline over the ridge is laid in such a way that it is not Solid circular section is shown below. more than 6.4 m above the hydraulic gradient. Moment of area A1 and A2 about neutral axis gives Zp. 𝑨 𝝅𝑫𝟐 Also, A1 = A2 = = 𝟐 𝟖 𝝅𝑫𝟐 𝟒 𝑫 𝑫𝟑 Hence, 𝒁𝒑 = 𝟐 × ( )× × = 𝟖 𝟑𝝅 𝟐 𝟔 Now Z about neutral axis is given by 𝝅𝑫𝟑 𝒁= 𝟑𝟐 𝒁𝒑 𝟏𝟔 So, shape factor = = 𝒁 𝟑𝝅 Q.44. What is the shear area of a rolled steel I-section for minor axis bending? (Where h-overall depth; b-breadth; tw-thickness of web; tf-thickness of flange) (a) htw (b) 2btf Q.42. A rapid test to indicate the intensity of pollution (c) btf (d) htf of water is- Ans. (b) The shear area Av for different sections is given (a) Total Dissolved Solids below : (b) Biochemical Oxygen Demand (i) The major axis bending of I and channel sections (c) Most Probable Number (d) Dissolved Oxygen Av = htw (Hot rolled) Av = dtw (Welded) Ans. (d) Total Dissolved Solids (TDS) : A measure of the total amount of dissolved solids in water. (ii) The minor axis bending of I and channel sections Av = 2btf (Hot rolled or welded) RRB JE Civil 19 September 2019 10 Civil KI Goli (iii) Rectangular hollow tubes of uniform thickness Ans. (c) Hipped Roof : This roof is formed by four Av = Ah/(b+h) (Loaded parallel to depth h) sloping surface is four directions. At the end faces Av = Ab/(b+h) (Loaded parallel to width b) sloping triangle are formed. (iv) Circular hollow tubes of uniform thickness Av = 2A/π (v) Plates and solid bars Av = A A = cross-sectional area b = overall breadth of the tubular section, the breadth of I section flanges d = clear depth of the web between the flanges Q.45. Which type of beam, freely supported at two points, has one or both ends extending beyond these Q.47. A simply supported beam is subjected to a supports? linearly varying load from one end to other end. The nature of variation of shear force diagram is- (a) Simply supported beam (b) Cantilever beam (a) Elliptic (b) Parabolic (c) Fixed beam (c) 3rd degree curve (d) Linear (d) Overhang beam Ans. (b) The general relationship between the shear Ans. (d) Overhanging beam : force diagram, bending moment diagram, and loading diagram will be : 1. Shear force diagram is 1o higher than the loading diagram. 2. Bending moment diagram is 1o higher than the shear force diagram. n Degree of SFD & BMD Diagram for various loading tio If the end portion of a beam extends beyond the nc support, then the beam is known as overhanging Ju il beam. Overhanging may be on one of the supports or iv C on both sides. In the case of an overhanging beam, the bending moment is positive between the supports, whereas the bending moment is negative for the overhanging portion. At the same point on the beam, the bending moment is zero or changes sign from a positive to a negative value or vice versa. This point where the bending Q.48. The unit of viscosity is- moment changes sign is called the point of contra flexure or point of inflection. (a) m-kg/hr (b) kg/m-hr2 (c) kg/m-hr (d) kg/m2 Ans. (c) The S.I. and C.G.S. units are discussed below. Units of Viscosity S.I. System Pascal Second or Kilograms per meter per second or Kg/m-s, kg/m-hr Q.46. A hipped roof is- C.G.S. System Poise (P) or Grams per (a) One which has at least two different types of centimeter per second or covering materials g/m-s. (b) One which has at least two different slopes Q.49. At a point in a steel member, major and minor (c) One which slopes in four directions principal stress in 1000 kg/cm2, and minor principal (d) One which slopes in two directions stress is compressive. If uniaxial tensile yield stress is RRB JE Civil 19 September 2019 11 Civil KI Goli 1500 kg/cm2,then magnitude of minor principal stress Q.51. Which type of gate is generally used for low at which yielding will commence, according to navigation dams? maximum shearing stress theory is- (a) Bear trap gate (b) Vertical lift gate (a) 200 (b) 500 (c) Rolling gate (d) Drum gate (c) 600 (d) 1000 Ans. (a) Bear trap gates : Ans. (b) Maximum shear stress theory Bear trap gates are also known as movable drum (Guest & Tresca’s Theory) According to this theory, gates. failure of the specimen subjected to any combination A bear trap gate consists of two leaves of steel, with of a load when the maximum shearing stress at any one leaf hinged on the upstream side and the other point reaches the failure value equal to that developed on the downstream side over the crest. at the yielding in an axial tensile or compressive test of The bear trap gates are suitable for low navigation the same material. dams. These gates have a wide base but a deep recess is not required. These gates may be designed to operate automatically. Q.52. _________ testing is probably the most frequently used means of NDT. (a) Rebound hammer (b) Acoustic mapping τmax ≤ σy For no failure (c) Radar 𝟐 (d) Ultrasonic pulse velocity σy Ans. (d) Non-destructive tests are used to find the σ 𝟏 − σ𝟐 ≤ ( ) For design strength of existing concrete elements. They are FOS σ1 and σ2 are maximum and minimum principal stress classified as follows. respectively. 1. Half-cell electrical potential method: Here, τmax = Maximum shear stress It is used to detect the corrosion potential of reinforcing σy = permissible stress bars in concrete. This theory is well justified for ductile materials. 2. Schmidt or Rebound hammer test: σ2 = 1000 kg/cm2 and σy = 1500 kg/cm2 It is used to evaluate the surface hardness of concrete. 3. Carbonation depth measurement test: σy It is used to determine whether moisture has reached τmax ≤ 𝟐 the depth of the reinforcing bars. 4. Permeability test: 𝝈𝟏 −(−𝝈𝟐 ) σy ≤ It is used to measure the flow of water through the 𝟐 𝟐 1000+σ2 = 1500 concrete. σ2 = 500 kg/cm2 5. Penetration resistance or Windsor probe test: Q.50. The yield strength and ultimate strength of 4.6 It is used to measure the surface hardness and hence grade bolts are- the strength of the surface and near-surface layers. (a) 240 N/mm2 and 400 N/mm2 6. Ultrasonic pulse velocity test: (b) 20 N/mm2 and 28 N/mm2 It is mainly used to measure the time of travel of (c) 200 N/mm2 and 400 N/mm2 ultrasonic pulse passing through the concrete and (d) 200 N/mm2 and 280 N/mm2 hence concrete quality. Ans. (a) Bolts are classified as grade x. y where This method deals with the noting of time of travel of electronically generated mechanical pulse which is x represents 1/100th of ultimate tensile strength and further used to analyse the velocity of the pulse y represents the ratio of yield stress to ultimate through the structure that represents its quality. tensile stress. This test is used to establish uniformity of concrete, For a bolt of grade 4.6 implies that: Pressure of cracks and voids, Quality of concrete in Ultimate strength, f = 4 x 100 = 400 N/mm² relation to standard requirements, estimation of Yield strength, f, = 0.6 x ultimate strength pulse modulus of elasticity, estimation of the strength = 0.6 x 400 = 240 N/mm² of concrete, determination of setting characteristics RRB JE Civil 19 September 2019 12 Civil KI Goli  of concrete, estimation of crack depth, measurement of the thickness of concrete pavement. Q.54. ________ are much larger than capillary pores. This test calculates the dynamic modulus of elasticity (a) Air voids (b) Micro cracks of concrete. (c) Blow holes (d) Macro cracks Velocity of Pulse Ans. (a) Air voids are essentially empty spaces within a Quality of concrete (km/sec) material that are not filled with solid material or water. > 4.5 Excellent These voids can be formed during the mixing and 3.5 to 4.5 Good placing of concrete, as a result of entrapped air. 3 to 3.5 reasonable 3 (c) Iron oxide (d) Alumina where Ans. (b) Silica : Silica provides strength to the cement. D60 = size at 60% finer by weight Silica in excess causes the cement to set slowly. D30 = size at 30% finer by weight Lime : Lime is the major ingredient of cement. It makes D10 = size at 10% finer by weight = Effective size the cement sound and also provides strength to the cement. Lime in excess makes the cement unsound and CIVIL JUNCTION causes the cement to expand and disintegrate. The RRB JE Civil 19 September 2019 24 Civil KI Goli