Concrete J-Ring Test Apparatus for SCC is used to evaluate the passing ability and flow performance of fresh self-compacting concrete. It is suitable for laboratory testing of SCC and helps assess concrete flow through reinforcement gaps.

Concrete J-Ring Test Apparatus for SCC  

Model: TD533

I. Product Application

The Self-Compacting Concrete J-Ring Test Apparatus is mainly used to test the passing ability of fresh self-compacting concrete through narrow gaps. The apparatus complies with the requirements of JGJ/T 283-2012, Technical Specification for Application of Self-Compacting Concrete, and JTG 3420-2020, Test Methods of Cement and Concrete for Highway Engineering.

Reference Standards: ASTM C1621/C1621M-17(2023), EN 12350-12:2010

II. Technical Specifications

1. J-ring: Diameter 300 mm;

2. Rebar diameter: φ18 mm;

3. Number of rebar rods: 16.

III. Test Procedure

1. Fill a 10 L metal bucket with 6–7 L of fresh concrete and allow it to stand for 60 s ± 10 s.

2. During the 60 s ± 10 s resting period, wet the base plate and slump cone with a sponge or towel. Ensure that there is no standing water on the inner wall of the slump cone or on the base plate. Place the base plate on a firm, level surface. Position the slump cone upright at the center of the base plate, with its lower edge aligned with the 200 mm marked circle. Place the J-Ring around the slump cone, with its lower edge aligned with the 300 mm marked circle. Keep the slump cone firmly in position during filling.

3. Pour the concrete from the metal bucket into the slump cone. Fill the cone continuously in one layer until full, without applying any vibration or tamping during the entire filling process.

4. Use a trowel to strike off the excess concrete at the top of the slump cone until it is flush with the upper edge of the cone. Remove any excess concrete around the slump cone on the base plate. Then, immediately lift the slump cone vertically and smoothly. The time interval from filling the slump cone to lifting it shall not exceed 40 s. The lifting process shall be completed within 3–7 s, allowing the concrete to flow freely. The entire process, from the start of filling to the lifting of the slump cone, shall be performed continuously and completed within 150 s.

5. When the concrete mixture stops spreading or the spreading time reaches 50 s, measure and record the maximum diameter D1 of the spread concrete and the diameter D2 perpendicular to D1. The final slump flow diameter (D) of the concrete mixture is calculated as the average of the two diameters. The measurement shall be accurate to 1 mm, and the result shall be rounded to the nearest 5 mm.

IV. Product Features

The Concrete J-Ring Test Apparatus for SCC is designed with a rigid metal J-ring and evenly arranged reinforcing steel rods to provide a stable and reliable test setup. The apparatus is suitable for evaluating the flowability and passing ability of fresh self-compacting concrete under laboratory conditions.

The J-ring test can be used together with a slump cone and base plate to assess the ability of self-compacting concrete to flow through restricted spaces. The test results can help evaluate the filling and passing performance of SCC around reinforcing bars.

V. Application

This J-Ring Test Apparatus is suitable for concrete laboratories, construction material testing laboratories, universities, research institutes, quality inspection organizations, and construction projects. It is applicable to the testing and quality control of self-compacting concrete (SCC) and other fresh concrete mixtures requiring passing ability evaluation.

VI. Product Advantages

Suitable for self-compacting concrete (SCC) passing ability testing;

Rigid and durable metal J-ring structure;

300 mm diameter J-ring with 16 reinforcing rods;

Suitable for laboratory and quality control applications;

Can be used with a slump cone and base plate;

Simple operation and convenient measurement;

Suitable for concrete material testing and research.