00193795

Component

http://onlinepubs.trb.org...s/trr/1978/675/675-004.pdf

http://scholar.google.com...hnes&publication_year=1978

The theoretical basis of mercury intrusion porosimetry is reviewed, and the limitations of the Washburn equation as a means of converting the test data to a pore-size distribution curve are discussed. A procedure is suggested to distinguish the volume of pores with uniform radii from the volume of nonuniform of "ink-bottle" pores. The depressurization curve that results from reducing the pressure on mercury to allow retraction and ejection of mercury from the pores does not coincide with the pressurization curve. This hysteresis is attributed to the presence of ink-bottle or nonuniform pores. Physicochemical factors such as chemisorption and the difference in the contact angle of advancing and retreating mercury menisci contribute slightly to this hysteresis. Consideration of pore geometries demonstrates that the ejection pressure may not be equal to the intrusion pressure for a pore of given size. A comparison of the intrusion, depressurization, and reintrusion of two hypothetical samples illustrates the advantage of the second intrusion for interpreting pore-size distribution curves. The second intrusion gives the distribution of uniform pores and volumes of ink-bottle pores intruded at each entrance diameter. Finally the second-intrusion method is applied to portland cement pastes with a 0.4 water-cement ratio that were hydrated for 3 and 60 d. It is observed that 60 to 64 percent of the porosity is in uniform pores that have a size distribution curve similar to the first-intrusion curve. /Author/

This paper appeared in TRB Record 675, Moisture and Frost-Related Soil Propertes. Publication of this paper sponsored by Committee on Physico-chemical Phenomena in Soils. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.

01411514

pp 15-20

1978

Transportation Research Record

Digital/other

Figures (7) ; References (15)

Hysteresis; Mercury; Pore size distribution; Porosity; Pressure

Geotechnology; Highways

TRIS, TRB

May 11 1979 12:00AM

• EFFECT OF DRYING TEMPERATURE ON THE INDEX PROPERTIES OF CALCRETES
• EFFECTS OF WATER ADSORPTION ON KAOLIN CLAY DURING SHEAR
• EXPANDED POLYSTYRENE CONCRETE SUBBASES
• LABORATORY EVALUATION OF MATERIALS AND DESIGN CHARACTERISTICS OF PENNDOT UNDERDRAIN SYSTEM
• PHASE COMPOSITION MEASUREMENTS ON SOILS AT VERY HIGH WATER CONTENTS BY THE PULSED NUCLEAR MAGNETIC RESONANCE TECHNIQUE
• SOME FACTORS THAT AFFECT THAW STRAIN