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C-1 ATTACHMENT C Recommended Standard Test Methods These proposed test methods are the recommendations of the NCHRP Project 18-12 staff at the University of Sherbrooke. These test methods have not been approved by NCHRP or any AASHTO committee nor formally accepted for the AASHTO Specifications.

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C-3 CONTENTS C-4 Filling Capacity of Self-Consolidating Concrete Using the Caisson Test C-7 Surface Settlement Test to Evaluate Static Stability of Concrete C-11 Reference

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C-4 Recommended Standard Method of Test for Filling Capacity of Self-Consolidating Concrete Using the Caisson Test AASHTO Designation: T XXX 1. SCOPE 1.1 This test method covers the determination of filling capacity of self-consolidating concrete. 1.2 The test method is limited to self-consolidating concrete having a nominal size aggregate of 1 in. [25 mm]. 1.3 The values stated in either inch-pounds or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations to use. Warning--Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure (Note 1). Note 1--The safety precautions given in the Manual of Aggregate and Concrete Testing, located in the related section of Volume 04.02 of the Annual Book of ASTM Standards, are recommended. 1.5 The text of these standard reference notes provides explanatory material. These notes (excluding those in tables and figures) shall not be considered as requirements of the standard. 2. REFERENCED DOCUMENTS 2.1 AASHTO Standards R 39, Making and Curing Concrete Test Specimens in the Laboratory T 141, Sampling Freshly Mixed Concrete 2.2 ASTM Standards C 125, Terminology Relating to Concrete and Concrete Aggregates C 1621, Standard Test Method for Passing Ability of Self-Consolidating Concrete by J-Ring 3. TERMINOLOGY 3.1 Definitions For definitions of terms used in this test method, refer to Terminology C 125 3.2 Definitions of Terms Specific to This Standard Filling abilityThe ability of self-consolidating concrete to flow under its own mass and completely fill formwork (ACI 237). Passing abilityThe ability of self-consolidating concrete to flow under its own weight (without vibration) and fill completely all spaces within intricate formwork containing obstacles, such as reinforcement (ASTM C 1621). Filling capacityThe ability of self-consolidating concrete to flow and completely fill all spaces within the formwork. 4. SUMMARY OF THE TEST METHOD 4.1 The caisson filling capacity test is used to assess the filling capacity of the self-consolidating concrete. Self-consolidating concrete is introduced from tremie pipe equipped with hopper at a constant rate in a container with obstacles until the concrete rises in the caisson to a height of 9 in. [225 mm]. The area occupied by the concrete in the restricted section is used to calculate the filing capacity.

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C-5 5. SIGNIFICANCE AND USE 5.1 This test method provides users with a laboratory procedure to determine the potential filling capacity of self-consolidating concrete. 5.2 This test method shall be used to develop self-consolidating concrete mixtures with a high level of workability. Self- consolidating concrete is a fluid concrete that can be prone to segregation if not proportioned to be cohesive. A cohesive self-consolidating concrete is important for all applications but is especially critical for deep and highly reinforced sections. 6. APPARATUS 6.1 Caisson--The caisson measuring 19.7 11.8 5.9 in. [500 300 150 mm] L H W in dimension shall have a flat and smooth surface. In the container are 35 obstacles made of copper with a diameter of 0.6 in. [16 mm] and a distance center to center of 2 in. [50 mm], as shown in Fig. 1. 6.2 Measuring Device--Ruler, metal roll-up measuring tape, or similar rigid or semi-rigid length-measuring instrument marked in increments of 0.25 in. [5 mm] or less. 6.3 Sample Receptacle--The receptacle shall be a heavy gage metal pan, wheelbarrow, or flat, clean non-absorbent board of sufficient capacity to allow easy remixing of the entire sample with a shovel, trowel, or scoop. 6.4 Tremie Pipe--The tremie pipe shall have a minimum diameter of 3.94 in. [100 mm]. Clear acrylic plate Tremie pipe Copper tube 12.5 mm 16 mm diameter 50 mm 300 mm 34 mm 150 mm 350 mm 100 mm = 3.94 in. Figure 1. Details of caisson. 7. SAMPLE 7.1 Obtain a sample of freshly mixed self-consolidating concrete in accordance with Test Method T 141 and place it in the sample receptacle in accordance with Practice R39. 8. PROCEDURE 8.1 Perform the filling capacity test on a flat, level surface. Do not subject the testing surface to any vibration or disturbance. 8.2 Remixing of Sample--Remix the sample obtained in accordance with Section 7.1 in the sample receptacle using a shovel or scoop so that the concrete is homogeneous. 8.3 Filling the Mold--Using a bucket, fill the caisson with concrete at a constant rate of approximately 0.7 ft3/min [20 L/min] until the concrete rises in the caisson to a height of 9 in. [225 mm]. 8.4 Wait for the concrete to stop flowing and then measure the height of concrete from h1 to h8, as shown in Fig. 2. Determine the filling capacity in accordance with Section 9 of this test method.

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C-6 9. CALCULATION 9.1 Calculate the filling capacity using the following equation: 7 (hi + hi+1 ) FC ( % ) = i =1 100 h1 14 where: FC = Filling capacity hi = Height of concrete at i position H1 H2 H3 H4 H5 H6 H7 H8 hi = 300 mm Hi 100 mm = 3.94 in. Figure 2. Details on calculation of filling capacity. 10. REPORT 10.1 Mixture designation. 10.2 The h values at different positions. 10.3 The filling capacity to the nearest 2%. 11. PRECISION AND BIAS 11.1 Precision--The estimate of the precision of this test method is provisional. A repeatability standard deviation of 1.2% was obtained from a study (1) involving five replicate batches of a concrete mixture with a mean filling capacity of 94%. 11.2 The procedure used in this test method has no bias since filling capacity of self-consolidating concrete is defined only in terms of this method. 12. KEYWORDS 12.1 coarse aggregate; self-consolidating concrete; stability; filling capacity; passing ability

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C-7 Recommended Standard Method of Test for Surface Settlement Test to Evaluate Static Stability of Concrete AASHTO Designation: T XXX 1. SCOPE 1.1 This test method is used to evaluate the static stability of concrete, including self-consolidating concrete, from a plastic state after placement until the time of hardening by measuring the total surface settlement and rate of surface settlement at early age of concrete cast in a cylindrical specimen (or column). 1.2 The test method can be used for self-consolidating concrete and conventional concrete. 1.3 The values stated in either inch-pounds or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations to use. Warning--Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure (Note 1). Note 1-The safety precautions given in the Manual of Aggregate and Concrete Testing, located in the related section of Volume 04.02 of the Annual Book of ASTM Standards, are recommended. 1.5 The text of these standard reference notes provides explanatory material. These notes (excluding those in tables and figures) shall not be considered as requirements of the standard. 2. REFERENCED DOCUMENTS 2.1 AASHTO Standards R 39, Making and Curing Concrete Test Specimens in the Laboratory T 141, Sampling Freshly Mixed Concrete 2.2 ASTM Standards C 125, Terminology Relating to Concrete and Concrete Aggregates D 1785, Specifications for Poly(Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120 3. TERMINOLOGY 3.1 Definitions For definitions of terms used in this test method, refer to Terminology C 125. 3.2 Definitions of Terms Specific to This Standard Static Segregation, n--Resistance to segregation when no external energy is applied to concrete, namely from imme- diately after placement and until setting (ACI 237). 4. SUMMARY OF THE TEST METHOD 4.1 A sample of freshly mixed self-consolidating concrete is placed in a cylindrical mold without tamping or vibration. A dial gage or a linear variable differential transformer (LVDT) is placed on top of a thin acrylic plate placed at the upper surface of the concrete. The initial reading is taken after the installation of the monitoring set-up. Changes in height are monitored until reaching steady state condition. The difference in height indicates the settlement of the concrete.

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C-8 5. SIGNIFICANCE AND USE 5.1 This test method provides users with a laboratory procedure to determine the potential static segregation of concrete, including self-consolidating concrete. 5.2 This test method shall be used to develop concrete, including self-consolidating concrete mixtures with segregation not exceeding specified limits. Self-consolidating concrete is a fluid concrete that can be prone to bleeding and segregation if not proportioned to be cohesive. A stable self-consolidating concrete is important for all applications but is especially critical for deep sections, such as walls or columns. Therefore, the surface settlement can indicate if a mixture is suitable for the application. Surface settlement shall affect the development of homogeneous distribution of in-situ properties of the hardened concrete, including bond to reinforcement. 6. APPARATUS 6.1 Column mold--The column shall be PVC plastic pipe, Schedule 40, meeting the requirements of Specifications D 1785. The column shall be 8 in. [200 mm] in diameter 26 in. [660 mm] in height. The column shall be securely attached to a non-absorbent, rigid base plate measuring at least 12 in. [300 mm] 12 in. [300 mm] square, as shown in Fig. 1. 6.2 Dial gage or LVDT--The dial gage with a 0.0004 in. [0.01 mm] precision or a LVDT with a minimum travel range of 2 in. [50 mm]. 6.3 Acrylic plate--The plate shall be 6 in. [150 mm] in diameter and 0.15 in. [4 mm] in thickness with four holes measuring /2 in. [0.4 mm] for the escape of bleed water, as shown in Fig. 1. 1 Schedule 40 PVC Pipe 200 mm Dial gage 150 mm 12.5 mm hole 4 mm thin acrylic plate 660 mm 35 mm screw 500 mm Concrete Specimen Sealed or Laminated Plywood 300 mm 20 mm 300 mm 100 mm = 3.94 in Figure 1. Details of surface settlement test.

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C-9 6.4 Screw--Four 1.4 in. [35 mm] screws for the positioning of the acrylic plate, as shown in Fig. 1. 6.5 Sample receptacle--The receptacle shall be a heavy gage metal pan, wheelbarrow, or flat, clean non-absorbent board of sufficient capacity to allow easy remixing of the entire sample with a shovel, trowel, or scoop. 6.6 Small tools--Tools and items such as shovels, plastic pails, trowels, scoops, and rubber gloves shall be provided. 7. SAMPLE 7.1 Obtain a sample of freshly mixed self-consolidating concrete in accordance with Test Method T 141 and place it in the sample receptacle in accordance with Practice R39. 8. PROCEDURE 8.1 Perform the surface settlement test on a flat, level surface. Do not subject the testing surface and the column mold to any vibration or disturbance. 8.2 Remixing of Sample: Remix the sample obtained in accordance with Section 7.1 in the sample receptacle using a shovel or scoop so that the concrete is homogeneous. 8.3 Filling Procedure: Using a shovel, scoop, or plastic pail, immediately fill the column mold with concrete up to 19.7 in. [500 mm] height, within 2 min. 8.4 Carefully install the acrylic plate with the screws in the center of the column. 8.5 Install the dial gage or LVDT in the center of the acrylic plate. The initial reading of the dial gage or LVDT is taken 60 sec- onds after the installation of the monitoring set-up. Settlement values are taken at 5-minute intervals for the first 30 min- utes and then every 2 hours until hardening of the concrete. 9. CALCULATION 9.1 Calculate the Surface Settlement* using the following equation: HI - HF S (%) = 100% HC where: S = Surface settlement (%) HI = Initial reading of the dial gage or LVDT HF = Final reading of the dial gage or LVDT HC = Height of the concrete in the column *The maximum surface settlement shall be obtained using the settlement value at the time of concrete hardening. 9.2 Calculate the rate of surface settlement between 10 and 15 minutes using the following equation: S -S Rate of Settlement ( % hr ) = 15 10 100% % 60 where: Rate of Settlement = Rate of surface settlement between 25 and 30 minutes S15 = Surface settlement at 15 minutes (%) S10 = Surface settlement at 10 minutes (%)

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C-10 10. REPORT 10.1 Mixture designation. 10.2 The variation height obtained from the dial gage or LVDT at different time. 10.3 The maximum surface settlement to the nearest 0.01%. 10.4 The rate of settlement between 10 and 15 minutes to the nearest 0.01%. 11. PRECISION AND BIAS 11.1 Precision--The estimate of the precision of this test method is provisional. A repeatability standard deviation of 0.02% was obtained from a study (1) involving five replicate batches of a concrete mixture with a mean maximum surface settlement of 0.16%. Settlement rates of concrete determined at 15, 30, and 60 minutes after the beginning of surface settlement testing can be correlated to the maximum settlement values. The 15-minute rate of settlement can be used to estimate the maximum surface settlement. 11.2 Bias--The procedure used in this test method has no bias since surface settlement of self-consolidating concrete is defined only in terms of this method. 12. KEYWORDS 12.1 coarse aggregate; self-consolidating concrete; stability; static stability; surface settlement

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C-11 Reference (1) J., Assaad, K. H., Khayat, and J., Daczko, "Evaluation of Static Stability of Self-Consolidating Concrete," ACI Materials Journal, Vol. 101, No. 3, MayJune 2004, pp. 207215.