Understanding Flexure Strength in Reinforced Concrete Beams
School
De La Salle University**We aren't endorsed by this school
Course
CEE 42
Subject
Mechanical Engineering
Date
Dec 11, 2024
Pages
3
Uploaded by BrigadierPencilGerbil43
HomeT-CEET325 CEE32 2nd Sem ( 2022-2023 )MODULE 2: Analysis for flexure strength of reinforced concrete - Part 1Short Quiz 2SubmissionsHere are your latest answers:Question 1_____ rectangular beams are those which comprise of reinforcement both in the tension and compression zone.Response: Doubly ReinforcedScore: 2 out of 2 YesQuestion 2Which among the following statements are not true?Response: a is always greater than cResponse: In the analysis of the stress block, the curved stress diagram is replaced with a rectangular diagram with a constant stress of 75 percent offc'Response: Stress, like strain always vary directly as the distance from the neutral axis or as a straight line.Score: 2 out of 2 YesQuestion 3Which beam failure stage is when the tensile stresses are less than the modulus of rupture?Response: uncracked stageScore: 2 out of 2 YesQuestion 4The bending tensile stress of concrete at which it begins to crack is independent on the density of concrete.Response: FalseScore: 2 out of 2 YesQuestion 5Transformed area analysis or transformed area (or section) method is used when the section is said to be homogeneous, i.e., made of 2 or morematerials with different moduli of elasticity.Response: FalseScore: 2 out of 2 YesQuestion 6Which among the following equations/relationships are never/not correct?Response: C = 0.85fc' bdResponse: Mu≥ øMn
Response: Score: 2 out of 2 YesQuestion 7Match the symbols/notations with their correct description/definition.Response: Ec=> modulus of elasticity of concreteResponse: fc'=> specified compressive strength of concreteResponse: fs=> tensile stress in reinforcement at service loadsResponse: fy=> specified yield strength of non-prestressed reinforcementScore: 2 out of 2 YesQuestion 8This assumption on flexure analysis on beams implies a perfect bond between the concrete and the steel, as both must act together to carry load.Which is it?Response: The strain in the reinforcement is equal to the strain in the concrete at the same level.Score: 2 out of 2 YesQuestion 9Which of the following relationship in strains is true with over reinforced beam?Response: εs < εyScore: 2 out of 2 YesQuestion 10In this stage of beam failure, the strains are small, and the moment-curvature diagram is nearly vertical and very close to a straight line. Which stageis it?Response: uncracked stageScore: 2 out of 2 YesQuestion 11The under reinforced type of beam is generally adopted when due to head room consideration or architectural consideration, the depth (or size) ofbeam is restricted and can not therefore develop the compression force required to resist the given bending moment, hence there is a need to reinforceit for compression.Response: FalseScore: 2 out of 2 YesQuestion 12Match the symbol/notation with the correct definition/description.Response: As => area of non prestressed longitudinal tension reinforcementResponse: c => distance from extreme compression fiber of the beam to the neutral axis
Response: Mn => nominal flexural strength at sectionResponse: n => modular ratio of elasticityScore: 2 out of 2 YesQuestion 13The bending tensile stress of concrete at which it begins to crack is dependent on its specified compressive strength.Response: TrueScore: 2 out of 2 YesQuestion 14The most common governing load factor combination for when only deadload (D) and live loads(L) are the only load in consideration is : _____ D +_____ LResponse: 1.2Response: 1.6Score: 2 out of 2 YesQuestion 15Match the symbols/notations with their correct description/definition.Response: β1=> factor relating depth of equivalent rectangular compressive stress block to depth ofneutral axisResponse: εcu=> maximum usable strain at extreme concrete compression fiberResponse: εy=> net tensile strain in extreme layer of longitudinal tension reinforementResponse: d=> Distance from extreme compression fiber to centroid of longitudinal tensionreinforcementScore: 2 out of 2 Yes