This standard is issued under the fixed designation C ; the number 1 This test method is under the jurisdiction of ASTM Committee C-9 on Concrete. thank you so much for your answer, but i need whole the norme in PDF if possible As per ASTM C, I5 is defined as the area under the load- deflection. C Standard Test Method for Flexural Toughness and First-Crack Strength of Fiber-Reinforced Concrete (Using Beam With Format, Pages, Price. PDF.
|Language:||English, German, French|
|ePub File Size:||16.47 MB|
|PDF File Size:||10.78 MB|
|Distribution:||Free* [*Registration needed]|
ASTM C - Download as PDF File .pdf), Text File .txt) or read online. Norma encargada de ver ensayos de materiales en el ámbito de la construcción. ASTM C is a standard test method for the flexural toughness and first crack strength of fiber-reinforced concrete. A 14x4x4 inch (xx mm) beam is. According to ASTM C , the toughness or energy absorption is defined as the area under the load-deflection curve up to a specific deflection levels.
The addition of fibers to the concrete have wide range of usage due to their evident advantages over ordinary concrete. The function of the use of fibers in concrete is to enhance the mechanical properties of concrete. Fibers used to modify the flexural strengths, toughness, impact resistance, fracture energy, and restrain crack formation. The concrete with fibers as additives used widely in highways, tunnel linings, concrete pipes, reinforced concrete frames, reinforced concrete beam members, shell roof systems, skyscrapers, pre-stressed concrete, light shell constructions, domes and folded plates in recent years .
Plain concrete unreinforced concrete breakdown suddenly when the deflection corresponding to the ultimate flexural strength exceeded, oppositely FRC continues to withstand considerable loads even at deflections significantly in excess of the fracture deflection of the plain concrete .
The fractured specimens of FRC exhibits that failure takes place chiefly due to fiber pull-out or debonding. Therefore, FRC specimen does not break immediately after first crack as shown in Figure 1. This has the effect of increasing the work of fracture, which denoted to as toughness and represented by the area under the load-deflection curve .
The specimen for a flexural strength test matching to ASTM C 78  and ASTM C  should be confirmed to the dimensions in Figure 2 a and b , and shows the planning and arrangement for the flexural strength test. Beside, in ASTM 3 C  the span length of test specimen divided in two portions and the ratio of the straight distance between the point of load All rights reserved by www.
In general, the span of the specimen have 2 three times of the depth. The specimen turn on its side with respect to its position as molded and center it on the support blocks. Load-applying blocks upper roller should be in contact with the surface of the specimen before applied load, and should be vertical to the face of the specimen and applied without eccentricity.
Also, the load is operated at rate 0. According to the mechanics of materials, the flexural strength can calculated as shown in Figure 3 a and b. In ASTM C 78  third-point loading, the middle third portion distance between upper roller bearing of the beam is subjected to pure bending if the fracture occurs inside the middle third, and the flexural strength can be calculated as presented in Figure 3.
But, if the fracture occurs outside the middle third as shown in Figure 4, the specimen is involving bending moment and shear force, so the flexural strength can be calculated as following [8, 10]. The results of the flexural strength test according to ASTM C  center-point loading gives 13 percent higher than third- point loading .
All rights reserved by www.
AMERICAN SOCIETY FOR TESTING AND MATEAIALS
It is performance of areas under the load-deflection curve or area under stress-strain achieved by testing a simply supported beam under third-point loading. The reading done at sufficiently frequent intervals to ensure accurate reproduction of the load-deflection curve. The depth and width of test specimens shall be at least three times of the maximum fiber length.
ASTM C  test method provides the determination of a number of ratios called toughness indices. These indices are determined by dividing the area under the load-deflection curve obtained by third point loading flexural test, the area up to the deflection at which first crack deemed to have occurred. The first crack strength represents the behavior of fiber reinforced concrete to the inception of crack in the matrix.
But, the toughness indices In and residual strength R factors characterize the level of strength retained after first crack up to specified endpoint deflection, and represent the average post-crack load retained over a specific deflection interval as a percentage of the load at first crack are derived from these indices.
For plain concrete considered as a brittle material and, so the various toughness indices in its case are equal to one. Additionally, the residual strength factors represent the remaining strength in fiber reinforced concrete derived from the toughness indices . The residual strength factors for plain concrete, its brittle response, consequently, have residual strength factors equal to zero.
ASTM C 1018
Finally, concluding from ASTM C  some limitations that its influence on the efficiency of the test. Load- deflection curve should be accurately due to toughness indices depended on it. American Concrete Institute, Measurement of properties of fibre reinforced concrete. ACI Journal, 75 7 —9.
Google Scholar 5.
Toughness Testing of Fibre Reinforced Concrete
Johnston, C D. Cement, Concrete and Aggregates, 4 2 61—7. CrossRef Google Scholar 6. Barr, B.
CrossRef Google Scholar 7. CrossRef Google Scholar 8. Magazine of Concrete Research, 37 — CrossRef Google Scholar 9. Japan Concrete Institute, Method of test for flexural strength and flexural toughness of fibre reinforced concrete.
Standard SF4. Google Scholar Zollo, R.
R, Fibrous concrete flexural testing—developing standardised techniques. ACI Journal, 77 5 —8.N OTE 1 I-Location of deflection-measuring devices at the midwidth of the specimen minimizes the effect of twisting and reduces the number of devices needed to determine the net deflection at the mid-span.
Google Scholar 4. The results of tests of beams with steel libers longer than one-third the width or depth of the beam may not be comparable to test results of similar-sized beams with fibers shorter than one-third the width or depth because of possible preferential fiber alignment, and dinerent size beams may not be comparable because of size effects.
For plain concrete considered as a brittle material and, so the various toughness indices in its case are equal to one. N OTE When the flexural strength is required, It may be determined using the maximum load attained on the load-deflection curve and the formula for modulus of rupture given in Test Method C
- UNDERSTANDING POINTERS IN C YASHWANT KANETKAR PDF
- BRETONNIAN ARMY BOOK PDF
- FREE LABEL PDF
- UCO BANK ATM APPLICATION FORM PDF
- APOSTILA TCE SP 2015 PDF
- LUCENT GENERAL KNOWLEDGE 2013 PDF IN HINDI PDF
- EBOOK PHP LENGKAP
- MERCY THOMPSON T8 PDF
- TURBOFAN AND TURBOJET ENGINES DATABASE HANDBOOK EBOOK
- CCNP ROUTE OFFICIAL CERTIFICATION GUIDE PDF
- SAFETY OF LIFE AT SEA BOOK
- SHRIMAD BHAGWAT MAHAPURAN IN GUJARATI PDF
- OLD WORLD OF DARKNESS PDF
- BRS BEHAVIORAL SCIENCE 5TH EDITION PDF