A Study of the Interactions of Selected Combinations of Subgrade and Base Course Subjected to Repeated Loading : Technical Paper

The Effect of Base Course Gradation on the Results of Laboratory Pumping Tests : Technical Paper

“…It has been pointed out (17) In only one caae (n s 0.5) did a test specimen with a sand base course exhibit pumping of fine soil from the base, and this was very minor in extent (see Table 2). In three cases (n = 1.2, n = 1.5, and n a 2.0) a small amount of subgrade intrusion was noted.…”

Repeated Load Triaxial Test with Pore Pressure Measurement : Technical Paper

“…A recently concluded program of research (1) Havers (2) in his study of subgrade pumping. The loading energy is provided by compressed air actuating a piston type air cylinder.…”

The Effect of Base Course Gradation on the Results of Laboratory Pumping Tests

“…The movement of subgrade ceil into the interstices between base course particles It has been postulated (17) that this might result from the release of pore water pressure developed in a softened subgrade soil resulting from the transmis: ion of load through a granular base course to the subgrade surface. A distinction is made here between this aspect of pump.…”

“…Measurements of the total deflection of the subgrade-base course system were taken intermittantly during each test. kt the end of each test, the weight of soil pumped to the base course surface was measured and a grain size analysis was performed on the base course sample to determine the increase in soil finer than the No This investigation consisted of twe s, an extensive field and office correlative study of highway and airfield pavements (32)* and a statistical laboratory study to evaluate the relative influence of various subgrade and base course factors on the pumping of rigid pavements- (17),…”