Alternative Cap Materials for Evaluating the Compressive Strength of Controlled Low-Strength Materials
Publication: Journal of Materials in Civil Engineering
Volume 15, Issue 5
Abstract
This research investigated the influence of different capping materials on the compressive strength of controlled low-strength material (CLSM). These capping materials included a sulfur compound, gypsum capping compound, and neoprene pads with different durometer hardness values. Neoprene pads with Shore A durometer hardness values of 20, 40, 50, 60, and 70 were incorporated into the test program. A total of eight CLSM mixtures that covered a wide range of mixture compositions was included in this study. Sulfur capping compound was found to generate the most consistent compressive strength values and was thus used as a control in qualifying other capping materials. With a slightly modified ASTM C 1231 procedure, neoprene pads with a Shore A durometer value equal to or less than 50 were qualified to yield compressive strength values not less than 80% of the corresponding value from the sulfur mortar capping compound results at a significance level of 5%, as required in ASTM D 4832. At this same level of significance, the compressive values from CLSM cylinders capped with gypsum capping compound were found to be more than 92% of the control values from the sulfur mortar capped cylinder results. But, this capping procedure was found to be more time consuming than the neoprene pad testing. As such, sulfur capping compound and neoprene pads with a Shore A durometer value of not more than 50 are recommended to evaluate the compressive strength of CLSM cylinders.
Get full access to this article
View all available purchase options and get full access to this article.
References
American Concrete Institute (ACI) Committee 229. (1999). “ACI 229R-99 report in controlled low-strength materials (CLSMs).”American Concrete Inst.
ASTM C 33. (1997). “Standard specification for concrete aggregates.” Annual Book of ASTM Standards, Section 4—Construction, Volume 04.02—Concrete and Aggregates, West Conshohocken, Pa.
ASTM C 39. (1996). “Standard test method for compressive strength of cylindrical concrete specimens.” Annual Book of ASTM Standards, Section 4—Construction, Volume 04.02—Concrete and Aggregates, West Conshohocken, Pa.
ASTM C 150. (1997). “Standard specification for Portland cement.” Annual Book of ASTM Standards, Section 4—Construction, Volume 04.01—Cement; Lime; Gypsum, West Conshohocken, Pa.
ASTM C 617. (1994). “Standard practice for capping cylindrical concrete specimens.” Annual Book of ASTM Standards, Section 4—Construction, Volume 04.02—Concrete and Aggregates, West Conshohocken, Pa.
ASTM C 618. (1998). “Standard specification for coal fly ash and raw or calcined natural Pozzolan for use as a mineral admixture in concrete.” Annual Book of ASTM Standards, Section 4—Construction, Volume 04.02—Concrete and Aggregates, West Conshohocken, Pa.
ASTM C 1231. (1993). “Standard practice for use of unbonded caps in determination of compressive strength of hardened concrete cylinders.” Annual Book of ASTM Standards, Section 4—Construction, Volume 04.02—Concrete and Aggregates, West Conshohocken, Pa.
ASTM D 2166. (1991). “Standard test method for unconfined compressive strength of cohesive soil.” Annual Book of ASTM Standards, Section 4—Construction, Volume 04.08—Soil and Rock (1), West Conshohocken, Pa.
ASTM D 4832. (1995). “Standard test method for preparation and testing of controlled low strength material (CLSM) test cylinders.” Annual Book of ASTM Standards, Section 4—Construction, Volume 04.08—Soil and Rock (1), West Conshohocken, Pa.
Carrasquillo, P. M., and Carrasquillo, R. L.(1988). “Effect of using unbonded capping systems on the compressive strength of concrete cylinders.” ACI Mater. J., 85(3), 141–147.
Crouch, L. K., and Pearson, J. B.(1995). “Neoprene capping for static modulus of elasticity testing.” ACI Mater. J., 92(6), 643–648.
Crouch, L. K., Knight, M. L., Henderson, R. C., and Sneed, W. A. (1999a). “Unbonded capping for concrete masonry units.” Masonry: Materials, testing, and applications, ASTM STP 1356, J. H. Brisch, R. L. Nelson, and H. L. Francis, eds., ASTM, 62–74.
Crouch, L. K., Henderson, R. C., and Sneed, W. A., Jr. (1999b). “Development of an unbonded capping system for clay masonry prisms.” Masonry: Materials, testing, and applications, ASTM STP 1356, J. H. Brisch, R. L. Nelson, and H. L. Francis, eds., ASTM, 105–115.
Folliard, K. J., Trejo, D., Sabol, S. A., and Du, L. (2001). “Controlled low-strength material for backfill, utility bedding, void fill and bridge approaches.” Research Interim Rep. No. NCHRP 24-12(1).
Johnson, C. D., and Mirza, S. A.(1995). “Confined capping system for compressive strength testing of high performance concrete cylinders.” Can. J. Civ. Eng., 22(3), 617–620.
Pistilli, M. F., and Willems, T.(1993). “Evaluation of cylinder size and capping method in compression strength testing of concrete.” Cem. Concr. Aggregates,15(1), 59–69.
Richardson, D. N.(1990). “Effects of testing variables on the comparison of neoprene pad and sulfur mortar-capped concrete test cylinders.” ACI Mater. J., 87(5), 489–495.
Sauter, H. J., and Crouch, L. K.(2000). “An improved capping technique for excavatable controlled low-strength material compressive strength cylinders.” J. Test. Eval., 28(3), 143–148.
Tikalsky, P. J., Gaffney, M., and Regan, R.(2000). “Properties of controlled low-strength material containing foundry sand.” ACI Mater. J., 97(6), 698–702.
Vichit-Vadakan, W., Carino, N. J., and Mullings, G. M.(1998). “Effect of elastic modulus of capping material on measured strength of high-strength concrete cylinders.” Cem. Concr. Aggregates,20(2), 227–234.
Information & Authors
Information
Published In
Copyright
Copyright © 2003 American Society of Civil Engineers.
History
Received: Apr 22, 2002
Accepted: Sep 13, 2002
Published online: Sep 15, 2003
Published in print: Oct 2003
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.