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24 Table 3.14. Mixture proportions for the temperature and drying effects study. Cement Fly Ash Concrete Air Fly Ash Water Flow Density Mixture Content Content Sand Content Type a (kg/m 3 ) (mm) (kg/m 3 ) (kg/m 3 ) (kg/m 3 ) (kg/m 3 ) (%) H-1 60 F 1200 None 492 220 2.4 1631 H-2 15 F 240 1500 197 240 1.2 2191 H-3 15 C 240 1500 175 240 1.4 2212 H-4 30 C 180 1500 181 200 1.2 2163 H-5 30 F 180 1500 188 220 1.4 2210 H-6 60 None 0 1500 123 190 25.5 1603 a F= Class F, C = Class C. dry materials (fine aggregate, fly ash, and cement) were first CLSM containing bottom ash has been shown by the re- mixed with approximately half of the expected mixing water searchers (and others) to be an effective method of reduc- (based on trial mixing) for 3 minutes, followed by a ing segregation and bleeding while maintaining the required 2-minute rest period. After the rest period, the remainder of workability. the batched water was added, followed by 3 additional minutes of mixing. Immediately after mixing, flow measurements were taken. In most cases, because of the benefit of trial mixing, the Fresh CLSM Test Methods target flow of 200 to 250 mm was obtained. If the flow was less than desired, small amounts of water were added, followed by Flow an additional minute of mixing to obtain the target flow. For Immediately after mixing, the flow was measured following some mixtures the desired minimum flow was difficult to ASTM D 6103. This method, which measures the diameter achieve because of tendencies for bleeding and segregation. In of a CLSM "pancake" after a 75 150 mm cylinder is slowly those cases flow values less than 200 mm were accepted. lifted, was found to be generally easy to perform and was also For mixing air-entrained CLSM, mixing water was held quite reproducible. back and a relatively dry consistency (i.e., zero slump) mixture was obtained in the mixer. An AEA specifically formulated for CLSM was then added with additional water. This process was Air Content and Unit Weight necessary because of the high potency of the AEA. If the AEA was added to an already fluid mixture, the flow would far ex- ASTM C 231 (pressure method), which is typically used for ceed the desired range and the mixture would often suffer from conventional concrete, was used, with slight modification, to excessive bleeding. The researchers found obtaining both the measure the air content and unit weight of fresh CLSM mix- desired flow and air content to be challenging (but generally tures. The only modification was that the material was placed feasible). in one layer without rodding, instead of being placed in three The researchers did not focus on optimizing the mixture equal layers and then consolidated. proportions for optimal workability (i.e., flow, bleeding, etc.); the main objective was to obtain valid and direct com- Setting Time and Bleeding parisons of constituent material types and contents. How- ever, with high amounts of fines and/or air entrainment, Setting and hardening of CLSM mixtures were evaluated selected mixtures can be modified to obtain desired work- using three methods: needle penetration (ASTM C 403), soil ability levels. For example, introducing additional fly ash to penetrometer (or "pocket" penetrometer), and pocket vane Table 3.15. Mixture proportions for triaxial shear and water permeability studies. Air Fresh Dry Moisture Cement Fly Ash Sand Water Flow Mixture Content Density Density Content (kg/m 3 ) (kg/m 3 ) (kg/m 3 ) (kg/m 3 ) (mm) (%) (kg/m 3 ) (kg/m 3 ) (%) I-1 30 180 1500 283 200 1.3 2036 1746 16.55 I-2 60 180 1535 327 210 1.3 2077 1748 18.79 I-3 120 180 1485 335 220 0.7 2087 1759 18.61 I-4 60 0 1471 212 190 22.5 1607 1415 13.59 I-5 60 0 1181 172 210 27.0 1569 1381 13.65 I-6 60 1200 0 500 200 0.5 1529 1133 35.00

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25 Table 3.16. CLSM mixtures for corrosion study and their fresh properties. Air Cement Fine Aggregate Fly ash Fly Ash Water Flow Density Mixture Content (kg/m3) Typea, b (kg/m3) Typea, c (kg/m3) (mm) (kg/m3) (%) A1a 63 CS 1200 F 184 209 1.5 1605 A1b 63 1200 F 432 203 1.3 1591 A1c 63 1200 F 515 200 1.0 1605 A2a S 206 C 134 200 1.5 2177 A2b S 206 C 200 305 0.6 2180 A3a 30 CS 98 178 30.0 1602 A3b 30 S 118 200 25.0 1695 A3c 30 S 112 200 29.0 1593 A4a 15 CS 180 F 190 216 1.5 2194 A4b 15 S 180 F 204 229 1.3 2169 A4c 15 S 180 F 196 216 1.5 2167 A5a 30 CS 180 F 184 203 2.0 2185 A5b 30 S 180 F 188 203 2.3 2163 A5c 30 S 180 F 170 225 1.0 2177 A6a 15 CS 180 HC 190 210 2.0 2115 A6b 15 S 180 HC 224 203 2.0 2097 A6c 15 S 180 HC 216 206 1.0 2084 A7a 30 CS 180 HC 232 203 2.3 2099 A7b 30 S 180 HC 232 203 1.3 2111 A7c 30 S 180 HC 214 206 1.8 1978 A8a 15 CS 180 C 168 216 4.8 2155 A8b 15 S 180 C 168 216 1.8 2220 A8c 15 S 180 C 174.4 200 1.5 2179 B4a 30 CS 180 C 186 216 4.8 2170 B4b 30 S 180 C 144 216 1.3 2225 B4c 30 S 180 C 184 200 1.8 2228 B6a 30 CS 180 HC 472 209 2.3 1753 B6b 30 FS 180 HC 494 203 1.8 1765 B6c 30 FS 180 HC 524 200 1.5 1750 B7a 30 FS 180 C 484 222 1.5 1795 B7b 30 FS 180 C 426 229 3.0 1848 B9a 15 BA 180 HC 324 165 1.8 1821 B9b 30 BA 180 HC 324 145 2.8 1760 B10a 30 BA 180 C 318 175 1.5 1852 B10b 30 BA 180 C 318 200 2.0 1848 a "" indicates that this item was not used in the mixture. b Fine aggregate content was kept constant 1500 kg/m3. CS = Concrete Sand, S= Sand, FS = Foundry Sand, BA = Bottom Ash. c F = Class F, C = Class C, HC = High Carbon. shear testing. The setting and hardening of fresh CLSM sam- sisted of three separate cylindrical sections, was used for this ples that were placed in 150 150 mm containers were mea- purpose. Each cylindrical section had a diameter of 100 mm sured using a needle penetrometer and a soil penetrometer. and a height of 75 mm. The sections were connected verti- A larger container was used for measurements using the vane cally to produce a sample cylinder with a diameter of 100 mm shear tester. Before each measurement, the bleed water was and a height of approximately 225 mm. After the samples removed and weighed. had set, steel plates, acting as "guillotines," were inserted at Depth of penetration for the needle penetrometer and the the junctions between the cylinder sections, thus yielding soil penetrometer was approximately 25 mm and 6.4 mm, re- three separate samples (upper, middle, and lower). Each spectively. The pocket vane shear tester only measures the shear sample was then wet sieved, using the No. 4, No. 8, No. 16, resistance of CLSM at the upper 3 mm layer. No. 30, No. 50, No. 100, and No. 200 sieves. Each portion retained on these sieves was then dried in the oven at 110C for 24 hours and weighed. Material passing the No. 200 sieve Segregation was not collected. Using the resultant gradation from each of The segregation of six selected CLSM mixtures was mea- the three sections, a "pseudo" fineness modulus (FM) was cal- sured quantitatively. A specially designed mold, which con- culated, using the same mathematical approach as typically