An inverted T-shaped concrete beam (B1) in the figure, with centroidal axis X - X, is subjected to an effective prestressing force of 1000 kN acting at the bottom kern point of the beam cross-section. Also consider an identical concrete beam (B2) with the same grade of concrete but without any prestressing force.
Correct Answer: 299
Solution and Explanation
Top Questions on Concrete
Consider the beam section shown in the figure, with \( y \) indicating the depth of neutral axis (NA). The section is only subjected to an increasing bending moment. It is given that \( y = 18.75 \, {mm} \), when the section has not yielded at the top and bottom fibres. Further, \( y \) decreases to 5 mm, when the entire section has yielded. The shape factor of the section is ........ (rounded off to 2 decimal places).
- Consider a reinforced concrete beam section of 300 mm width and 700 mm depth. The beam is reinforced with the tension steel of 2000 mm² area at an effective cover of 50 mm. Concrete in the tension zone is assumed to be cracked. Assume the modular ratio of 12 and Young's modulus of 200 GPa for steel. When the extreme fibre in the compression zone undergoes the strain of 0.0004 due to the applied bending moment, the stress in the steel (in MPa) is ..... (rounded off to the nearest integer).
- Identify the FALSE statement from the following options:
Consider a reinforced concrete beam section of 350 mm width and 600 mm depth. The beam is reinforced with the tension steel of 800 mm\(^2\) area at an effective cover of 40 mm. Consider M20 concrete and Fe415 steel. Let the stress block considered for concrete in IS 456:2000 be replaced by an equivalent rectangular stress block, with no change in (a) the area of the stress block, (b) the design strength of concrete (at the strain of 0.0035), and (c) the location of neutral axis at flexural collapse.
The ultimate moment of resistance of the beam (in kN.m) is ___________ (round off to the nearest integer).
- Concrete of characteristic strength 30 MPa is required. If 40 specimens of concrete cubes are to be tested, the minimum number of specimens having at least 30 MPa strength should be
Questions Asked in GATE CE exam
- During determination of the bulk specific gravity of compacted bituminous specimen, the mass in air of the specimen is 1260 g and volume is 525 cm³. The density of water is 1.0 g/cm³. The theoretical maximum specific gravity of mix is 2.510. The percentage air voids in the compacted specimen is ......... (rounded off to 2 decimal places).
- GATE CE - 2025
- Gravity Dams and Spillways
In levelling between two points A and B on the opposite banks of a river, the readings are taken by setting the instrument both at A and B, as shown in the table. If the RL of A is 150.000 m, the RL of B (in m) is ....... (rounded off to 3 decimal places).
- GATE CE - 2025
- Surveying and Levelling
A one-way, single lane road has traffic that consists of 30% trucks and 70% cars. The speed of trucks (in km/h) is a uniform random variable on the interval (30, 60), and the speed of cars (in km/h) is a uniform random variable on the interval (40, 80). The speed limit on the road is 50 km/h. The percentage of vehicles that exceed the speed limit is ........ (rounded off to 1 decimal place).
- GATE CE - 2025
- Traffic signs
- A 5.0 m wide rectangular channel carries a discharge of 10 m³/s at a depth of 1.5 m under uniform flow. To produce critical flow conditions without affecting the upstream conditions, the channel bottom elevation should be raised (in m) by ........ (rounded off to 2 decimal places).
- GATE CE - 2025
- Microscopic and macroscopic parameters of traffic flow
- A symmetrical trapezoidal canal is 100 km long. The bottom width is 10 m and the side slope is 1 Horizontal : 1 Vertical. The average flow depth in the canal is 2.5 m throughout the month of April. The measurement from a Class-A evaporimeter in the vicinity of the canal indicated an average evaporation rate of 0.5 cm/day in April. The volume of water evaporated from the canal (in m³) in the month of April is close to ........ \(\times 10^3\) (rounded off to 1 decimal place).
- GATE CE - 2025
- Ground water hydrology