• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11
  12. 12
    12
  13. 13
    13

Steel Reinforcement Tension Test

Extracts from this document...

Introduction

Introduction: Steel Reinforcement Tension Test can be conducted in two experiment session: * Two deformed grade 460 high yield steel bars * Two plain round grade 250 mild steel bars Both steel bars conform to the relevant requirements of BS 4449:1988; have a nominal diameter of 20 mm, and a length of approximately 800 mm. Objectives: * Practice tension testing of steel bars as reinforcement for concrete according to Hong Kong current standards. * Determine geometrical and mechanical properties of steel reinforcements including nominal cross-sectional area, yield stress, tensile strength, nominal stress at fracture, and elongation over gauge length, reduction of cross-sectional area at necking section, and modulus of elasticity. * Check compliancy of the determined properties of the steel reinforcements with relevant Hong Kong standards. Apparatus: 1. Testing machine equipped with an extensometer with a plotter for drawing load-extension curve (fig. 1) Fig. 1 2. straight edge (fig. 2) Fig. 2 3. A caliper (fig. 3) Fig. 3 4. A metal saw for making marks on the specimens (fig. 4) Fig. 4 5. weighing equipment (fig. 5) Fig. 5 6. metal ruler (fig. 6) Fig. 6 Procedure: i. The mass (M) and length (L) of the bars were measured. The diameter of plain mild steel bar (Dp) was also measured. Dp is used in this experiment to calculate sectional area for comparison with the area derived from mass. ii. The specimens were slightly scribed at regular intervals using the metal saw. iii. The specimen was clamped into testing machine. iv. The extensometer was mounted on the specimen and the gauge length (Lg) ...read more.

Middle

The differences of the mild steel and high yield steel bars are shown below: Mild Steel High Yield Steel Appearance * Plain * Deformed Composition * Carbon 0.1-0.25% * Mn 0.5% * Carbon 0.6-0.99% * Mn 1.5% Properties * Good machinability * Ductility * Weldability * Toughness * Greater yield strength * Lower ductility Recognition * High density * High stiffness * become rusty easily in damp atmosphere * High density * High stiffness * More springy * More friction Cost * cheaper * comparatively expensive Products * Window frames * Pipes * Rivets * High strength wires * Bolts * Springs 3. Why their loadings are different? There are two factors affect the loadings. Firstly, it is because of the difference on the content of manganese(Mn). Manganese can stiffening the steels and improve the loading capacity. So, high yield steel bars (1.5%) have better loading than Mild steel (0.5%) because of the higher manganese content. Secondly, is because of the appearance. Deformed steel have greater surface area and the uneven surface, it can have more friction than plain steel. The higher friction can be a good support for loading. So, the high yield steel bars take the higher loading. 4. Comparison of the Young's modulus (E) between high yield steel and mild steel The elastic modulus of high yield steel bar is lower than that of mild steel bar. However, it is not reflect the strength of the steel. The modulus of elasticity is to measure the stiffness. It is not related to the strength. As Young's modulus (E) ...read more.

Conclusion

5. There may be some errors when we are reading the results. We should look carefully on reading of the meter of the machine. It is because the steel bar would drop very quickly when the steel bar has broken and the machine cannot apply the loading of the steel bar.It Will break suddenly on a particular meter and the reading of the meter would not stop when the sample fails. Conclusion: The table has shown the calculated results on nominal Area, yield Stress (nominal), tensile strength, stress at fracture, Young's modulus, percentage elongation over gauge length, percentage reduction of area of samples respectively. Sample Mild Steel High Yield Steel A B C D Length (mm) 800 800 800 800 Mass (kg) 1.9917 1.9917 1.9176 1.9367 Nominal Area (mm2) 317.15 317.15 305.35 308.39 Maximum load (kN) 150.9 142.2 189.8 191 Load immediately before the fracture (kN) 128 124 125 139 Extension (mm) 35 33 22 23 Diameter after stretching (mm) 13.95 14.62 12.97 13.19 Cross sectional area after stretching (mm2) 152.84 167.87 132.12 136.64 Yield stress 280.62 277.47 514.16 518.82 Tensile strength 475.8 448.37 621.58 619.35 Young's modulus 192915.08 210311.89 173960.05 184619.73 Stress at fracture 403.59 390.98 409.37 450.73 % elongation over gauge length (%) 35 33 22 23 % reduction of area (%) 51.81 47.07 56.73 55.69 After the steel reinforcement tension test, we found that high yield steel has higher loading capacity compared with mild steel bars. It is shown in the part of yield stress, tensile strength, modulus of elasticity, percentage elongation, reduction of cross-sectional area and the part of nominal stress at fracture. The uneven surface of the high yield steel bars provided more friction and hardness. ?? ?? ?? ?? ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our University Degree Engineering section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related University Degree Engineering essays

  1. Statics - Tensile Test

    Sample A Sample B Sample C Stress (kN/mm^2) 0.540 0.319 0.289 Strain 0.118 0.141 0.022 Young's Modulus (kN/mm^2) 4.56 2.44 12.45 Results Analysing these results we can determine the name of the type of metal, in this case Sample A: Aluminium; Sample B: Steel; Sample C: Cast Iron After analysing

  2. The object of this experiment is to determine the Liquid and Plastic Limits of ...

    foundations for a building or structure) the properties of the subsoil(s) must be assessed. These processes can also be carried out to confirm the suitability of the proposed component (i.e. foundation). Soil assessment can include classification, grading tests to establish shear strength and consolidation. The full range of methods for testing soils is given in BS 1377.

  1. ANSYS Fracture Analysis

    Figure 2 - Normalised Stress intensity factors table The interpolated point was found to lie at a value of K'1 =0.42 Pam1/2. The finite element that was carried out was a simple two-dimensional plate and therefore it was appropriate to use PLANE 82 as the element type.

  2. The aim of this laboratory experiment is to examine the tensile strength of three ...

    and it means that iron is combined with carbon. Iron and carbon, the simplest of the ferrous metals (Latin ferrum=iron), are the main elements of plain carbon steels. Low-carbon steels have a carbon content 0,1-0,3% in addition to impurities. This kind of steels cannot be directly hardened by heat treatment, but they can be readily carburized and case hardened.

  1. Stainless steels

    Then, in 1875, another Frenchman named Brustlein recognized the importance of carbon levels in addition to chromium. However, metallurgists of the 19th century were unable to produce the combination of low carbon and high chromium found in most modern stainless steels, and the high-chromium alloys they could produce were too brittle to be practical.

  2. HDTV - High Definition Television

    The Table 1: provide the description of the specifications and comparison figures for the difference. HDTV/SDTV orizontal line ertical line spect RatioFrame Rate SDTV 640 480 4:3 p, 60i, 30p, 2 SDTV 704 480 4:3 and 16:9 p, 60i, 30p, 2 HDTV 1280 720 16:9 0p, 30p, 24p HDTV 1920

  1. Shielded Metal Arc Welding

    The advantage of welding is that it produces joints with very high efficiency. The strength of joints that are welded continuously like full length can easily approach or exceed the strength of the base materials. It is made possible by selecting a joint design that provides greater cross-sectional area than

  2. How Realistic is the Carbon Emission Reduction Target (CERT)?

    It was produced at the United Nations Conference in 1997 and its main objective is the "stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system"ii i.e. to prevent climate change.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work