00755136

Component

https://doi.org/10.3141/1611-05

http://scholar.google.com...etry&publication_year=1998

Interactions of expansive clay soils with transportation facilities have caused billions of dollars of damage. In the process of determining agents and methodologies to overcome expansive clay behavior, multiple injections of chemical agents into the subgrade to modify clay behavior are most promising. A study was conducted to optimize a potassium-rich solution of four parts. The modifying solution has been injected into expansive clay subgrades with success since the early 1970s. A laboratory methodology was developed to inject specimens multiple times and to conduct swell tests. Screening tests were conducted to evaluate linear effects that each of the four constituents had on swell response through interpretation of a factorial design. Analysis of replicated tests, randomly arranged in blocks, revealed that one constituent had no effect on swell behavior. A central composite experimental design then was used to optimize the remaining constituents. The resulting response surface equation led to an optimal combination for swell abatement, confirmed during short- and long-term verification testing. The optimal blend of constituents was determined to reduce swell from 7.2% to 0.84% under injection situations simulating the field, and it was found to improve the reduction in swell by 2.6% compared with the original blend. In addition, X-ray diffraction (XRD) confirmed that modification of clay occurred. This study was unique in its use of laboratory simulation of multiple field injections and in its use of statistical analysis to minimize the number of tests needed to ensure confidence in the optimization sought.

This paper appears in Transportation Research Record No. 1611, Stabilization and Geosynthetics.

English

p. 38-45

1998

Transportation Research Record

0309064562

Figures (2) ; References (10)

Chemicals; Expansive clays; Laboratory tests; Optimization; Soil stabilization; Statistical analysis; Subgrade (Pavements); Swelling; Tests

Data and Information Technology; Geotechnology; Highways; I42: Soil Mechanics

TRIS, TRB, ATRI

Oct 28 1998 12:00AM

• BENEFITS OF USING GEOGRIDS FOR BASE REINFORCEMENT WITH REGARD TO RUTTING
• FORENSIC EVALUATION OF THREE FAILED CEMENT-TREATED BASE PAVEMENTS
• GEOGRID REINFORCING OF RECYCLED AGGREGATE MATERIALS FOR ROAD CONSTRUCTION: FINITE ELEMENT INVESTIGATION
• LABORATORY INVESTIGATION OF COAL WASTES FOR SECONDARY ROADS
• RESILIENT PROPERTIES AND FATIGUE DAMAGE IN STABILIZED RECYCLED AGGREGATE BASE COURSE MATERIAL
• STABILIZATION CHARACTERISTICS OF CLAYS USING CLASS C FLY ASH
• STABILIZATION OF SULFATE-CONTAMINATED CRUSHED CONCRETE BASE WITH TYPE V CEMENT AND FLY ASH
• STABILIZATION OF WEAK CLAY WITH STRONG SAND AND GEOGRID AT SAND-CLAY INTERFACE
• TENSILE PROPERTIES OF ASPHALT OVERLAY GEOSYNTHETIC REINFORCEMENT
• USING GEOGRIDS FOR BASE REINFORCEMENT AS MEASURED BY FALLING WEIGHT DEFLECTOMETER IN FULL-SCALE LABORATORY STUDY