Cone tipped cylindrical probe for use in groundwater testing

An in soil testing system for measuring soil parameters while being forcibly penetrated into the soil comprising:

• a probe having a plurality of sensors for measuring said soil parameters;
• said plurality of sensors including:
• first and second strain gauge load cells mounted within said probe, said first strain gauge load cell measuring forces resisting tip penetration by said probe, said second strain gauge load cell measuring lateral forces resisting penetration by said probe;
• and
• a pressure sensing device for measuring said pore water pressure in the soil at said plurality of depths of penetration, said pressure sensing device including a porous filter mounted in a conical tip of said probe and a pressure transducer mounted within said probe, said pressure transducer being connected to said porous filter;
• said plurality of sensors of said probe generating electrical signals representative of said soil parameters;
• means coupled to said probe for forcibly penetrating said probe into the soil;
• a digital computer coupled to said plurality of sensors to receive said electrical signals from said plurality of sensors, said digital computers processing said electrical signals to provide a designation of a soil type for the soil, a pressure dissipation curve for said pore water pressure in the soil at each of said plurality of depths of penetration of said probe and a time T50 required for a fifty percent pressure dissipation of said pressure dissipation curve at each of said plurality of depths of penetration of said probe;
• said digital computer calculating a hydraulic conductivity for each of said plurality of depths of penetration of said probe using the formula:
• k = r 2 279.12 × t 50 × α × q c
• where r is a radius for said probe stored in said digital computer, a is an empirical average coefficient for said soil type, and qc is an end bearing component of the forces resisting tip penetration by said probe;
• said digital computer calculating a water depth below surface for each of said plurality of depths of penetration of said probe using the formula:
• WDBS = MD - p p × 144 d w ( 5 )
• where MD is a measured depth for said probe, pp is a final pressure for said pressure dissipation curve and dw is a density for fresh water which is approximately 62.4 pounds per cubic foot;
• said digital computer generating a hydrostatic pressure profile which illustrates a final pressure point for the pressure dissipation curve of each of said plurality of depths of penetration of said probe;
• said digital computer providing a best fit line for the final pressure point of only completed pressure dissipation curves for each of said plurality of depths of penetration of said probe;
• a monitor coupled to said digital computer for displaying a penetrometer dissipation analysis window which includes the hydraulic conductivity and the water depth below surface calculated by said digital computer for each of said plurality of depths of penetration of said probe, said monitor displaying said hydrostatic pressure profile and said best fit line;
• said digital computer containing a Piezocone Dissipation Analysis computer software program, said Piezocone Dissipation Analysis computer software program calculating said hydraulic conductivity and said water depth below surface for each of said plurality of depths of penetration of said probe, said Piezocone Dissipation Analysis computer software program generating said hydrostatic pressure profile and said best fit line;
• said Piezocone Dissipation Analysis computer software program including an option program module, said option program module having an option which allows a user of said in soil testing system to select said option, said option when selected by said user providing a Coefficient of Permeability from a soil classification lookup table for each of said plurality of depths of penetration of said probe;
• said Piezocone Dissipation Analysis computer software program using said Coefficient of Permeability from said soil classification lookup table for each of said plurality of depths of penetration of said probe to generate a hydraulic conductivity profile, said hydraulic conductivity profile appearing on said monitor.