A weight of 300KN is supported by a short concrete column of size 250x250mm. The column is strengthened by 4 steel bars in the corners of total cross section area 6000mm^2. If the modulus of elasticity for steel is 15 times that for concrete, find the stresses developed in steel and concrete

A tensile test was performed on a metal specimen having a circular cross section with a diameter 0. 510 inch. For each increment of load applied, the strain was directly determined by means of a strain gage attached to the specimen. The results are, shown in Table: 1.5.1. a. Prepare a table of stress and strain. b. Plot these data to obtain a stress-strain curve. Do not connect the data points; draw a best-fit straight line through them. c. Determine the modulus of elasticity as the slope of the best-fit line.

How does a tensile stress differ from a compressive stress?

In concrete work, Fuller and Thompson (1907) suggested that a dense packing of grains can be achieved if the percent finer (p) and grain size (D) are related by the following equation, where n is a constant varying in the range of 0.3-0.6. Dmax is the size of the largest grain within the soil. p=(DDmax)n100 This equation is sometimes used in roadwork for selecting the aggregates. a. For n = 0.5, show that the soil is well graded. b. If n = 0.5 and Dmax = 19.0 mm, find the percentages of gravel, sand, and fines within the soil. Use the Unified Soil Classification System.

A tensile test was performed on a metal specimen having a circular cross section with a diameter of 1 2 inch. The gage length (the length over which the elongation is measured) is 2 inches. For a load 13.5 kips, the elongation was 4.6610 3 inches. If the load is assumed to be within the linear elastic rang: of the material, determine the modulus of elasticity.

A tensile test was performed on a metal specimen with a diameter of 1 2 inch and a gage length (the length over which the elongation is measured) of 4 inches. The dam were plotted on a load-displacement graph. P vs. L. A best-fit line was drawn through the points, and the slope of the straight-line portion was calculated to be P/L =1392 kips/in. What is the modulus of elasticity?

In Example Problem 12.1, a uniaxial composite material is made into a circular rod Vbith a 1.27-cm diameter from 70 volume percent continuous carbon fibers and 30 volume percent epoxy. The rod is subject to an axial force of 100,000 N. The composite matcrial in Example Problem 12.1 is to be replaced with a less expensive composite made of 70 volume percent continuous E-glass fibers and 30 volume percent epoxy. The elastic moduli are 5 GPa for the epoxy resin and 72.4 GPa fos the E-glass. (a) Compare the elastic modulus, composite strain, fiber and matrix stresses, and density of this composite with the carbon epoxy composite in Example Problem 12.1. Usc the density of UHM carbon, and assume the density of the epoxy is 1.2g/cm3 . (b) Can both the E-glass fiber and matrix withstand the applied force?

The frame of a space shuttle type vehicle must have a high yield strength and high stillness, and the most important design factor is weight. Of all the materials presented in this chapter, what material might be the most suitable for the frame of a space shuttle? Assume that there will be both tensile and compressive stresses. For a space shuttle, cost is not a limiting factor. (a) You can eliminate entire classes of materials from consideration with a brief statement about their unsuitability. (b) What material has the highest specific yield strength? Give the yield strength, specific gravity, specific yield strength, elastic modulus, and specific elastic modulus for this material. (c) What material has the highest specific elastic modulus? Give the yield strength, specific gravity, specific yield strength, elastic modulus, and specific elastic modulus for this material. (d) Compare the materials with the highest specific yield strength and highest specific elastic modulus for suitability in the space shuttle frame. (C) Discuss the suitability of the top-rated material for this design from the viewpoint of the ability to produce a frame.