1. A beam with width b = 300 mm and depth d = 600 mm is to be prestressed. Considering a 15% pre stress loss, compute the value of the final prestressing force P and eccentricity e. a) if the compressive stress is 21 MPa b) if the compressive stress at the bottom fiber is 12 MPa and the tensile stress at the top fiber is 2 MPa. c) if the compressive stress at the top fiber is 16 MPa and zero at the bottom fibers.

1. A beam with width b = 300 mm and depth d = 600 mm is to be prestressed. Considering a 15% pre stress loss, compute the value of the final prestressing force P and eccentricity e. a) if the compressive stress is 21 MPa b) if the compressive stress at the bottom fiber is 12 MPa and the tensile stress at the top fiber is 2 MPa. c) if the compressive stress at the top fiber is 16 MPa and zero at the bottom fibers.

Materials Science And Engineering Properties

1st Edition

ISBN:9781111988609

Author:Charles Gilmore

Publisher:Charles Gilmore

Chapter12: Composite Materials

Section: Chapter Questions

Problem 12.7P: Estimate the transverse tensile strength of the concrete in Problem 12.6.

See similar textbooks

Similar questions

1. A BEAM WITH WIDTH B=300 MM AND DEPTH D=600 MM IS TO BE PRE-STRESSED. CONSIDERING A 15% PRE-STRESS LOSS, COMPUTE THE VALUE OF THE FINAL PRE-STRESSING FORCE P AND ECCENTRICITY E. A. IF THE COMPRESSIVE STRESS AT TOP AND BOTTOM IS 21 MPA. B. IF THE COMPRESSIVE STRESS AT THE BOTTOM FIBER IS 12 MPA AND THE TENSILE STRESS AT THE TOP FIBER IS 2 MPA. C. IF THE COMPRESSIVE STRESS AT THE TOP FIBER IS 16MPA AND ZERO AT THE BOTTOM FIBERS.
The beam shown left below has the cross section shown right below. Determine(a)The maximum tensile fiber stress in the beam.(b)The maximum compressive fiber stress in the beam.(c)The shearing stress 50 mm below the top surface of the flange.(d) The maximum shearing stress
A beam with width b = 300 mm and depth d = 650 mm is to be prestressed. Considering a 15% pre stress loss, compute the value of thefinal pre stressing force P and eccentricity e.a. If the compressive stress of 21 MPa.b. If the compressive stress at the bottom fiber is 12 MPa and thetensile stress at the top fiber is 2 MPa.c. If the compressive stress at the top fiber is 16 MPa and zero at thebottom fibers
A rectangular steel block is 75 mm in the x-direction, 50 mm in the y-direction and 100 mm in the z direction. The block is subjected to triaxial loading consisting of three uniformly forces as follows: KN tension in the x-direction, 250 KN compression in the y-direction, and 240 KN tension in the z-direction. If u = 0.3 andE = 200 GPa, Determine the total resulting strain in the x- direction. %3D
Determine the prestressing steel area required for the precast concrete T-beam. Use the following data: Total moment = 250 kN-m Effective stress fse= 862 MPa Allowable concrete stress = f.=11 MPa Consider zero stress at the bottom of the beam I=3673x106 mm4 A=103125 mm² Eccentricity = 271.6 mm Centroid of steel is located at 100 mm from the bottom of the beam. Select one: a. 591.97 mm b. 789.29 mm 2. C. 443.98 mm 2. d. 986.61 mm
1. Shown is a composite plate joined together by rivets. The components consist of two tension bar plates that is % X 4 inch and riveted together by two splice plates which is 0.8 X 6 inch. Each rivet has a diameter of 25.4 mm. Considering that the allowable stress for the tension bar plates and splice plates is o=20.0 ksi, the allowable shear stress for the rivets is o=25.0 ksi and the allowable bearing stress on the rivets and splice plates is o=25.0 ksi. What will be the maximum permissible load P such that none of the allowable stresses will be exceeded? Splice Plates a-0.75 in Bar Lc =0.80 in. Bar P d = 1.0 in. b=4.0 in. Rivets 'e = 6.0 in.
A rectangular steel block is 75 mm in the x-direction, 50 mm in the y-direction and 100 mm in the z direction. The block is subjected to triaxial loading consisting of three uniformly forces as follows: 24 KN tension in the x-direction, 250 KN compression in the y-direction, and 240 KN tension in the z-direction. If u = 0.3 and E = 200 GPa, Determine the total resulting strain in the z- direction. Note: CN is the last 2 non zero digits of your cellphone number
A pretensioned member with a dimension of 250mm x 360mm is subject to an eccentric tendon that is located 105mm from the soffit. Area of the prestressing steel to be 502 sq. mm and the modulus of elasticity is 200 GPa. The Modulus of elasticity of concrete is 36.8 GPa. Creep coefficient = 1.6 and the shrinkage strain = 3 x10^6. Assume a 5% steel relaxation. Find the total prestressed loss in percentage.
Beam AZ, 2 in wide and 4 in high, is subjected to a loading condition as shown. Determine: a. the maximum fiber stress b. the stress in a fiber located 0.5 in from the bottom of the beam midspan.
A rectangular pretensioned beam has concentric prestress force of 1000 KN. The beam is 300 x 500 mm in dimension and M20 grade of concrete is used with creep coefficient of 1.6 and residual shrinkage strain of 3 x10-4. Ast = 500 sq.mm. Find the following: a. Loss due to elastic shortening use Est = 200 GPa and Ec = 5700(Fc)^1/2 b. Loss due to creep c. Loss due to shrinkage d. Total loss of prestress
Q2: A cold drawn steel rod of circular cross- section is subjected to a variable bending momen of 565 N.m to 1130 N-m as the axial load varies from 4500 N to 13 500 N. Determine the required diameter of the rod for a factor of safety 2. Neglect any stress concentration and column effect. Assume the following values: Ultimate strength = 550 MPa Yield strength = 470 MPa Size factor = 0.85 %3D Surface finish factor = 0.89 Correction factors = 1.0 for bending = 0.7 for axial load The endurance limit in reversed bending may be taken as one-half the ultimate strength.
A rectangular plate is subjected to uniform biaxial stress with x = 90 MPa (tension), oy = -20 MPa (compression), and ₂ = 0. The plate has original dimensions 400 X 800 X 200 mm (x X y X z) and is made of steel with E = 200 GPa and v = 0.3. What are the strains Ex, Ey, and Ez?