ASTM Standards: C 31 Practice for Making and Curing Concrete Test Speci- mens in the Field2. C 42 Test Method for Obtaining and Testing Drilled Cores. C78 / C78M Standard Test Method for Flexural Strength of Concrete (Using Simple Beam with Standard + Redline PDF Bundle, 10, $, ADD TO CART . Flexural Strength of Concrete (Using Simple Beam with Third-Point Loading)1. 1 This test method is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregatesand is the direct responsibility of Subcommittee C on Testing for Strength. 2 Annual Book of ASTM.
|Language:||English, Spanish, Indonesian|
|Genre:||Business & Career|
|Distribution:||Free* [*Register to download]|
Cpdf - Download as PDF File .pdf), Text File .txt) or read online. This test method is under the jurisdiction of ASTM Committee C09 on than 21⁄2 in. P. F. N/A. Item. 1. Protect specimen from loss of moisture. 2. Turn test specimen on its side with respect to its position as molded and center on. determined by standard test methods ASTM C (third-point loading) or ASTM C (center-point loading). The specimen size and type of loading does.
Schubert et al. Xiao et al. Without this background, there is no quantitative basis for safely implementing RAC in structural design. Consequently, the authors, in conjunction with the Missouri Department of Transportation MoDOT , developed a testing plan to evaluate shear strength of RAC specimens with local materials.
The mix designs, based on standard mixes currently used by MoDOT, was on the lower end of cement content in order to develop a relatively harsh mix to investigate constructability issues common to RAC.
The experimental program, test results, and analyses for this study are presented in the following discussion.
Experimental investigation This mix design was used to construct control specimens to serve as baseline comparisons to the RAC mix and will also serve as parent material for the RCA source. The resulting concrete was ground at 28 days of age into aggregate with a maximum nominal aggregate size of 25 mm.
The Los Angeles abrasion test results were virtually identical. All of the reinforcing bars were from the same heat of steel, used the same deformation pattern, and met the requirements of ASTM A Table 2 shows the tested mechanical properties of the reinforcing steel.
The concrete mixtures with a target compressive strength of 35 MPa were delivered by a local ready-mix concrete supplier Rolla, MO. The purpose of using the ready-mix supplier was to validate the RAC concept in actual concrete production runs. The mixture proportions, fresh and hardened properties of both the CC and RAC mixes are given in Tables 3 and 4, respectively. Details of test beams Six beams without stirrups were constructed for each concrete type.
Beams with three different longitudinal reinforcement ratios 1. All beams tested in this program had a rectangular cross section with a width of mm, a height of mm, a length of mm, and shear span-to-depth ratios of 3.
The beam designation included a combination of letters and numbers: NS stands for no stirrups and numbers 4, 6, and 8 indicate the number of 22 22 mm diameter longitudinal reinforcement bars within the tension area of the beam section. For example, NS-6 indicates a beam with no stirrups within the shear test regions and 6 22 bars within the bottom of the beam. Test setup and procedure 3. Testing facilities A load frame was assembled and equipped with two kN, servo-hydraulic actuators intended to apply the two point loads to the beams.
The load was applied in a displacement control method with a rate of 0.
The shear beams were supported on a roller and a pin support, mm from each end of the beam, creating a four-point loading situation with the two actuators Fig. Table 1 Aggregate properties.
If the class is not specied, the requirements for Class 3S, 3M, or 1N shall apply in the severe, moderate, and negligible weathering regions, respectively see Table 3 and Fig. NOTE 8The specier of the aggregate should designate the class of coarse aggregate to be used in the work, based on weathering severity, abrasion, and other factors of exposure. See Table 3 and Fig.
The limits for coarse aggregate corresponding to each class designation are expected to ensure satisfactory performance in concrete for the respective type and location of construction. Selecting a class with unduly restrictive limits may result in unnecessary cost if materials meeting those require- ments are not locally available. C 33 result in unsatisfactory performance and premature deterioration of the concrete.
While concrete in different parts of a single structure may be adequately made with different classes of coarse aggregate, the specier may wish to require the coarse aggregate for all concrete to conform to the same more restrictive class to reduce the chance of furnishing concrete with the wrong class of aggregate, especially on smaller projects.
NOTE 9For coarse aggregate in concrete exposed to weathering, the map with the weathering regions shown in Fig. Those undertaking construc- tion, especially near the boundaries of weathering regions, should consult local weather bureau records for amount of winter precipitation and number of freeze-thaw cycles to be expected, for determining the weathering severity for establishing test requirements of the coarse aggregate.
For construction at altitudes exceeding m ft above sea level, the likelihood of more severe weathering than indicated by the map should be considered. In arid areas, severity of weathering may be less than that indicated.