Method of Test Splitting Tensile Strength of Concrete

IS 5816: Code of Practice for Splitting Tensile Strength of Concrete (Revised)

Scope (Summary)

• Applies to the determination of splitting tensile strength of concrete using cylindrical specimens.
• Relevant for quality control and design verification of concrete structures.
• Test method evaluates tensile strength indirectly by applying compressive load on a cylinder along its diameter.

Key Formula for Splitting Tensile Strength (f_ct,sp):

[ f_{ct,sp} = \frac{2P}{\pi LD} ]

Where:

• ( P ) = Maximum load applied (N)
• ( L ) = Length of the cylinder (mm)
• ( D ) = Diameter of the cylinder (mm)
• ( f_{ct,sp} ) = Splitting tensile strength (MPa)

Typical Specimen Dimensions:

• Diameter ( D = 150 ) mm
• Length ( L = 300 ) mm (2 × diameter)

Key Points:

• Test is done on cylindrical specimens.
• Load applied along the length on two opposite lines.
• Results correlate well with direct tensile strength of concrete.

flowchart LR
    A[Apply Load P] --> B[Concrete Cylinder]
    B --> C[Splitting along diameter]
    C --> D[Measure Load at Failure]
    D --> E[Calculate f_ct,sp = 2P / πLD]

For detailed procedures, refer to IS 5816 full text.

IS 5816 primarily deals with "Splitting Tensile Strength of Concrete" and does not have specific clauses titled "References" or "Departmental Forms."

Key Formulas from IS 5816:

• Splitting Tensile Strength, ( f_{ct} ):

[ f_{ct} = \frac{2P}{\pi LD} ]

Where:

• ( P ) = Maximum load applied (N)
• ( L ) = Length of the cylinder (mm)
• ( D ) = Diameter of the cylinder (mm)

Typical Test Setup:

• Cylinder placed horizontally between loading strips.
• Load applied diametrically until failure.

Important Specifications:

• Cylinder size: 150 mm diameter × 300 mm length (standard)
• Loading rate: 1.2 kN/s to 2.4 kN/s

Summary Table:

This formula and setup are essential for determining the tensile strength of concrete by splitting test per IS 5816.

IS 5816 pertains to "Splitting Tensile Strength of Concrete — Test Method," and its Terminology section defines key terms related to the test.

Key Terminology (IS 5816):

• Splitting Tensile Strength (ft): The tensile strength of concrete determined by applying a compressive load along the length of a cylindrical specimen, inducing tensile stress perpendicular to the load.

• Specimen: Usually a concrete cylinder of 150 mm diameter and 300 mm length.

• Load Application: Load is applied diametrically on the cylinder to cause splitting failure.

Important Formula:

The splitting tensile strength, ( f_t ), is calculated as:

[ f_t = \frac{2P}{\pi LD} ]

Where:

• ( P ) = Maximum applied load (N)
• ( L ) = Length of the cylinder (mm)
• ( D ) = Diameter of the cylinder (mm)

Typical Dimensions:

This terminology and formula are fundamental for understanding and performing the splitting tensile strength test as per IS 5816.

IS 5816 relates to Splitting Tensile Strength of Concrete — Test Method.

Apparatus as per IS 5816:

The standard specifies the following key apparatus for the test:

• Compression Testing Machine: Capacity of at least 2000 kN, with a uniform rate of loading.
• Cylindrical Moulds: Typically 150 mm diameter and 300 mm height for specimen casting.
• Bearing Strips: Wood or metal strips, 25 mm wide and 5 mm thick, placed between the specimen and loading surfaces to ensure uniform load distribution.
• Measuring Instruments: Vernier calipers or micrometers for measuring specimen dimensions.

Key Specifications:

• Loading Rate: Apply load at a constant rate so that failure occurs within 2 to 3 minutes.
• Specimen Size: Usually 150 mm diameter × 300 mm height cylinders.
• Test Setup: Load applied diametrically on the cylinder using bearing strips.

Formula for Splitting Tensile Strength (f_t):

[ f_t = \frac{2P}{\pi LD} ]

Where:

flowchart LR
    A[Compression Testing Machine] --> B[Specimen (Cylinder)]
    B --> C[Bearing Strips on top and bottom]
    C --> D[Load applied diametrically]
    D --> E[Measure max load P]
    E --> F[Calculate f_t = 2P / (πLD)]

This setup ensures uniform tensile stress distribution and accurate splitting tensile strength measurement.

IS 5816 covers "Splitting Tensile Strength of Concrete" test procedures.

Key Specifications for Test Specimen (IS 5816):

• Shape: Cylinder (commonly)
• Size:
  • Diameter (d) = 150 mm
  • Length (L) = 300 mm (L = 2d)
• Curing: Specimens should be cured as per IS 516 before testing.
• Condition: Test specimen should be free from cracks and defects.

Key Formula for Splitting Tensile Strength (f_t):

[ f_t = \frac{2P}{\pi d L} ]

Where:

• (P) = Maximum applied load (N)
• (d) = Diameter of cylinder (mm)
• (L) = Length of cylinder (mm)

Summary Table for Specimen Dimensions:

flowchart LR
    A[Test Specimen] --> B[Cylindrical Shape]
    B --> C[Diameter = 150 mm]
    B --> D[Length = 300 mm]
    A --> E[Curing as per IS 516]
    A --> F[Free from cracks]
    A --> G[Apply Load P]
    G --> H[Calculate f_t = 2P / (π d L)]

This ensures uniformity and accuracy in tensile strength testing of concrete.

IS 5816 deals with "Splitting tensile strength of concrete - Method of test". The Procedure for test is critical and involves:

Key Procedure Steps (IS 5816):

• Use a cylindrical specimen (typically 150 mm diameter × 300 mm height).
• Place specimen horizontally between loading surfaces.
• Apply load through a steel strip or bearing strips along the length.
• Load applied at a constant rate to cause failure by splitting.
• Record the maximum load (P) at failure.

Key Formula for Splitting Tensile Strength ( f_{sp} ):

[ f_{sp} = \frac{2P}{\pi LD} ]

Where:

• ( P ) = maximum applied load (N)
• ( L ) = length of cylinder (mm)
• ( D ) = diameter of cylinder (mm)

Typical Dimensions:

• Diameter ( D = 150 ) mm
• Length ( L = 300 ) mm

Notes:

• Ensure specimen is moist cured.
• Load applied at a rate of 0.7 to 1.4 MPa/min.

This method provides a direct measure of concrete's tensile strength, essential for design and quality control.

IS 5816 primarily deals with methods of test for splitting tensile strength of concrete.

Key Formula for Splitting Tensile Strength (ft)

The splitting tensile strength is calculated as:

[ f_t = \frac{2P}{\pi LD} ]

Where:

• ft = Splitting tensile strength (MPa)
• P = Maximum applied load (N)
• L = Length of the cylinder specimen (mm)
• D = Diameter of the cylinder specimen (mm)

Typical Specimen Dimensions (per IS 5816)

• Cylinder size: 150 mm diameter × 300 mm length
• Loading applied along the length of the cylinder

Test Setup Summary

• Load applied diametrically on the cylinder
• Load increased until failure
• Failure is a vertical crack along the loaded diameter

Important Notes

• Ensure uniform load application with strips or bearing plates.
• Testing rate: Load applied at a rate to cause failure in 2 to 3 minutes.
• Use moist-cured specimens for 28 days for standard results.

flowchart LR
    A[Cylindrical Specimen] --> B[Load Applied Diametrically]
    B --> C[Specimen Fails in Vertical Crack]
    C --> D[Record Maximum Load P]
    D --> E[Calculate ft = (2P) / (π L D)]

This formula and procedure provide the splitting tensile strength, a key parameter for concrete tensile behavior.

IS 5816: Test Report for Tensile Testing of Steel Reinforcement

Though IS 5816 does not explicitly provide a detailed "Test Report" format, key specifications and formulas for reporting tensile test results include:

Key Test Parameters to Report:

• Specimen identification
• Gauge length (Lo)
• Initial diameter or cross-sectional area (Ao)
• Maximum load (Pmax)
• Load at yield point (Py)
• Elongation at fracture (ΔL)
• Fracture type and location

Important Formulas:

Typical Test Report Table Format:

This format ensures compliance with IS 5816 tensile testing and clear communication of results.

IS 5816: Code of Practice for Splitting Tensile Strength of Concrete

While IS 5816 primarily deals with test methods for tensile strength, precautions during testing are critical for valid results. Although the code does not provide a dedicated clause on precautions, key standard practices include:

Key Precautions for Splitting Tensile Test (IS 5816):

• Specimen Preparation: Use cylindrical specimens (typically 150 mm diameter × 300 mm length).
• Surface Condition: Ensure smooth, clean, and plane loading surfaces; apply a thin plywood strip (10 mm thick) along the loading length to distribute load evenly.
• Alignment: Align specimen properly in the testing machine to avoid eccentric loading.
• Loading Rate: Apply load at a uniform rate of 0.7 to 1.4 MPa/min until failure.
• Machine Calibration: Use calibrated compression testing machines with a capacity at least 1.5 times the expected load.
• Avoid Shock Loading: Load must be applied gradually to prevent dynamic effects.

Formula for Splitting Tensile Strength, ( f_{ct} ):

[ f_{ct} = \frac{2P}{\pi L d} ]

Where:

• ( P ) = Maximum applied load (N)
• ( L ) = Length of the cylinder (mm)
• ( d ) = Diameter of the cylinder (mm)

Summary Table for Specimen Dimensions and Loading

flowchart LR
    A[Prepare cylindrical specimen] --> B[Place plywood strips]
    B --> C[Align specimen in machine]
    C --> D[Apply load at uniform rate]
    D --> E[Record maximum load P]
    E --> F[Calculate tensile strength using formula]

Note: Always refer to IS 5816 for detailed test procedure and calibration requirements.

IS 5816 deals with "Splitting Tensile Strength of Concrete — Method of Test." Since your query is about Notes but no specific clause is provided, here are the key points and formulas typically relevant:

Key Formula for Splitting Tensile Strength (ft)

The splitting tensile strength is calculated as:

[ f_t = \frac{2P}{\pi LD} ]

Where:

• P = Maximum applied load (N)
• L = Length of the cylinder (mm)
• D = Diameter of the cylinder (mm)

Typical Specimen Dimensions

• Cylinder size: 150 mm diameter × 300 mm length

Important Notes:

• Load is applied diametrically on the cylinder.
• Test should be conducted at 28 days curing age (or as specified).
• The value represents tensile strength indirectly by splitting.

Reference Table (Example):

If you need detailed departmental forms or CE timetables, those are administrative and not part of IS 5816 technical content.

graph LR
A[Apply Load P] --> B[Concrete Cylinder]
B --> C[Stress Distribution]
C --> D[Splitting Tensile Strength ft]