In a singly reinforced beam, the effective depth is measured from its compression edge to
1.tensile edge
2. tensile reinforcement
3.neutral axis of the beam
4.longitudinal central axis.
The maximum diameter of a bar used in a ribbed slab, is
1.12 mm
2.6 mm
3.20 mm
4.22 mm
The toe projection of foundation slabs is taken
1.as one third of the base
2.as one sixth of overall height of the wall
3.equal to heel slab
4. below ground surface.
A reinforced concrete cantilever beam is 3.6 m long, 25 cm wide and has its lever arm 40 cm. It carries a load of 1200 kg at its free end and vertical stirrups can carry 1800 kg. Assuming concrete to carry one-third of the diagonal tension and ignoring the weight of the beam, the number of shear stirrups required, is
1.30
2.35
3.40
4.45
If the depth of actual neutral axis of a doubly reinforced beam
1.is greater than the depth of critical neutral axis, the concrete attains its maximum stress earlier
2.is less than the depth of critical neutral axis, the steel in the tensile zone attains its maximum stress earlier
3.is equal to the depth of critical neutral axis, the concrete and steel attain their maximum stresses simultanesouly
4.all the above.
If the diameter of longitudinal bars of a square column is 16 mm, the diameter of lateral ties should not be less than
1.4 mm
2.5 mm
3.6 mm
4.8 mm
If the maximum shear stress at the end of a simply supported R.C.C. beam of 16 m effective span is 10 kg/cm2, the length of the beam having nominal reinforcement, is
1.4 cm
2.6 m
3.8 m
4.10 m
If the ratio of the span to the overall depth does not exceed 10, the stiffness of the beam will ordinarily be satisfactory in case of a
1.simply supported beam
2.continuous beam
3.cantilever beam
4.none of these.
In a simply supported slab the minimum spacing of distribution reinforcement, should be four times the effective thickness of the slab or
1.20 cm
2. 30 cm
3.40 cm
4. 60 cm
Pick up the incorrect statement from the following The intensity of horizontal shear stress at the elemental part of a beam section, is directly proportional to
1.shear force
2.area of the section
3.distance of the C.G. of the area from its neutral axis
4.moment of the beam section about its neutral axis
Steel beam theory is used for
1. design of simple steel beams
2.steel beams encased in concrete
3.doubly reinforced beams ignoring compressive stress in concrete
4. beams if shear exceeds 4 times allowable shear stress.
Steel beam theory is used for
1.design of simple steel beams
2. steel beams encased in concrete
3.doubly reinforced beams ignoring compressive stress in concrete
4.beams if shear exceeds 4 times allowable shear stress.
To ensure uniform pressure distribution, the thickness of the foundation, is
1.kept uniform throughout
2.increased gradually towards the edge
3.decreased gradually towards the edge
4.kept zero at the edge.
A T-beam behaves as a rectangular beam of a width equal to its flange if its neutral axis
1. remains within the flange
2.remains below the slab
3.coincides the geometrical centre of the beam
4. none of these.
According to I.S.: 456, 1978 the thickness of reinforced concrete footing on piles at its edges, is kept less than
1.20 cm
2. 30 cm
3.40 cm
4. 50 cm
Distribution of shear intensity over a rectangular section of a beam, follows :
1. a circular curve
2.a straight line
3.a parabolic curve
4.an elliptical curve
Distribution reinforcement in a simply supported slab, is provided to distribute
1.load
2.temperature stress
3. shrinkage stress
4. all the above.
For stairs spanning horizontally, the minimum waist provided is
1.4 cm
2.6 cm
3.8 cm
4.12 cm.
If a rectangular prestressed beam of an effective span of 5 meters and carrying a total load 3840 kg/m, is designed by the load balancing method, the central dip of the parabolic tendon should be
1.5 cm
2.10 cm
3.15 cm
4.20 cm
If the maximum shear stress at the end of a simply supported R.C.C. beam of 6 m effective span is 10 kg/cm2, the share stirrups are provided for a distance x from either end where x is
1. 50 cm
2.100 cm
3.150 cm
4.200 cm
If the permissible compressive and tensile stresses in a singly reinforced beam are 50 kg/cm2 and 1400 kg/cm2 respectively and the modular ratio is 18, the percentage area At of the steel required for an economic section, is
1.0.50%
2.0.60%
3.0.70%
4.0.80%
If the sides of a slab simply supported on edges and spanning in two directions are equal, the maximum bending moment is multiplied by
1.0.2
2.0.3
3.0.4
4.0.5
o ensure that the hogging bending moment at two points of suspension of a pile of length L equals the sagging moment at its centre, the distances of the points of suspension from either end, is
1.0.107 L
2. 0.207 L
3.0.307 L
4. 0.407 L
Pick up the incorrect statement from the following: Tensile reinforcement bars of a rectangular beam
1.are curtailed if not required to resist the bending moment
2. are bent up at suitable places to serve as shear reinforcement
3.are bent down at suitable places to serve as shear reinforcement
4. are maintained at bottom to provide at least local bond stress.
Pick up the true statement from the following:
1.Plain ceiling provides the best property diffusing light
2. In the absence of beams, it is easier to install piping
3. In the absence of beams, it is easier to paint
4.All the above.
The advantage of reinforced concrete, is due to
1.monolithic character
2.fire-resisting and durability
3. economy because of less maintenance cost
4.All the above.
The horizontal portion of a step in a stairs case, is known as
1.rise
2.flight
3.winder
4.tread.
The length of lap in tension reinforcement should not be less than the bar diameter x (actual tension / four times the permissible average bond stress) if it is more than
1. 18 bar diameters
2.24 bar diameters
3.30 bar diameters
4.36 bar diameters
The length of the straight portion of a bar beyond the end of the hook, should be at least
1.twice the diameter
2.thrice the diameter
3.four times the diameter
4.seven times the diameter.
The maximum ratio of span to depth of a cantilever slab, is
1.8
2.10
3.12
4.14
The maximum shear stress (qmax) in a rectangular beam is
1.1.25 times the average
2.1.50 times the average
3.1.75 times the average
4. 2.0 times the average
The radius of a bar bend to form a hook, should not be less than
1.twice the diameter
2.thrice the diameter
3.four times the diameter
4.five times the diameter
The shear reinforcement in R.C.C. is provided to resist
1.vertical shear
2. horizontal shear
3.diagonal compression
4. diagonal tension.
The thickness of the topping of a ribbed slab, varies between
1.3 cm to 5 cm
2.5 cm to 8 cm
3.8 cm to 10 cm
4.12 cm to 15 cm
The toe projection of foundation slabs is taken
1.as one third of the base
2.as one sixth of overall height of the wall
3.equal to heel slab
4.below ground surface.
The weight of a foundation is assumed as
1.5% of wall weight
2. 7% of wall weight
3.10% of wall weight
4.12% of wall weight
Total pressure on the vertical face of a retaining wall of height h acts parallel to free surface and from the base at a distance of
1.h/4
2.h/3
3.h/2
4.2h/3