Accession Number : AD0759903

Title :   Influence of Suction on Heave of Expansive Soils.

Descriptive Note : Final rept. Jul 70-Jun 71,

Corporate Author : ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MISS

Personal Author(s) : Johnson,Lawrence D.

Report Date : APR 1973

Pagination or Media Count : 84

Abstract : Certain types of foundation soils will swell from sorption of moisture, often causing differential heave and severe damage to overlying structures. A measure of the force causing these expansive soils to imbibe moisture is given by the magnitude of the negative pore water pressure (or suction) in the pore water of the soil. Estimations of heave and rates of heave in foundation soils can be made with suction data; however, information on the influence of suction has been limited. This investigation was conducted to determine the influence of suction pressures on heave in some expansive soils beneath structures. An important part of the project was the development and operation of a pressure membrane apparatus capable of simulating and measuring the in situ matrix suction of expansive clay soils. The relationship of suction of soil properties was reviewed, and some effects of field conditions on heave were examined. Selected expansive soils were tested under applied pressures simulating the in situ vertical loads. Specimens were obtained from sites located at Jackson, Mississippi, and Lackland Air Force Base, Texas. (Author Modified Abstract)

Descriptors :   (*SOILS, MOISTURE), (*FOUNDATIONS(STRUCTURES), DAMAGE), ADSORPTION, PRESSURE, TEST METHODS, PERMEABILITY, MEMBRANES, LOADS(FORCES), TEST EQUIPMENT, MILITARY FACILITIES

Subject Categories : Soil Mechanics
      Structural Engineering and Building Technology

Distribution Statement : APPROVED FOR PUBLIC RELEASE