Rate effects are examined in the steady pore pressure distribution induced as a result of penetration of standard and ball penetrometers. The incompressible flow field, which develops around the penetrometer is used to define the approximate soil velocity field local to the penetrometer tip. This prescribes the Lagrangian framework for the migration of the fluid saturated porous medium, definin...

A cone penetrometer is widely used in tillage and off-road mobility research as an indicator of soil strength and density characteristics. Light-weight, manually operated units are especially useful in recording cone index determination at remote field locations. An electronically hand-pushed soil penetrometer with a microcontroller-based data logging system was designed and fabricated to provi...

We explore the effect of microbial activity stimulated by root exudates on the penetrometer resistance of soil and its elastic modulus. This is important because it is a measure of the mechanical strength of soil and it correlates closely with the rate of elongation of roots. A sandy soil was incubated with a synthetic root exudate at different temperatures, for different lengths of time and wi...

Solution is developed for the build!up\ steady and post!arrest dissipative pore ~uid pressure _elds that develop around a conical penetrometer advanced in a poroelastic medium[ The analog with cone penetrometer testing is direct\ and is used to enable continuous distributions of permeability and di}usivity to be determined\ with depth[ Solution for a point normal dislocation migrating in a poro...

A 58-yearold burning and trashing trial receiving fertiliser and no fertiliser was used to quantify treatment effects on soil penetrometer resistance. The results showedthat penetrometer resistance was significantly lowerin thosetreatments whereno fertiliser wasapplied. Increased soilwatercontentin treatments witha trashcoverdid notreducepenetrometer resistance values in the soil wherefertilise...

Estimating penetrometer resistance and matric potential from the velocities of shear and compression waves Journal Article How to cite: Gao, W.; Watts, W. R.; Ren, T.; Shin, H.; Taherzadeh, S.; Attenborough, K.; Jenkins, M. and Whalley, W. R. (2013). Estimating penetrometer resistance and matric potential from the velocities of shear and compression waves. Soil Science Society of America Journa...

soil compaction is an important aspect of agriculture and different methods are available to measure this parameter. one method is called the cone index; measuring the force required per unit area for penetration of a standard steel cone into the ground. cone penetrometers are used for cone index measurement. in this study, a tractor mounted, hydraulically-operated penetrometer was designed, bu...

This paper presents an investigation on mechanism of the inclined 1 cone penetration test (CPT) using the numerical discrete element method (DEM). 2 A series of penetration tests with the penetrometer inclined at different angles 3 (i.e., 0°,15°, 30°, 45° and 60°) were numerically performed under µ=0.0 and 4 µ=0.5, where µ is the frictional coefficient between the penetrometer and the soil. 5 T...

The high inertia, i.e. high mass and low speed, of a landing spacecraft has the potential to drive a penetrometer into the subsurface without the need for a dedicated deployment mechanism, e.g., during Huygens landing on Titan. Such a method could complement focused subsurface exploration missions, particularly in the low gravity environments of comets and asteroids, as it is conducive to condu...

ters to characterize both agricultural and rangeland A DYNAMIC CONE PENETROMETER soils, however, has been limited by concerns about (i) FOR MEASURING SOIL instrument cost, (ii) measurement repeatability, (iii) limited ranges of soil resistance that can be measured by PENETRATION RESISTANCE a single penetrometer, and (iv) difficulties in comparing Jeffrey E. Herrick* and Tim L. Jones data collec...