36. Sinkhole House Testing Methods

Sinkhole testing method – Electrical Resistivity (ER) Imaging Principles Methods. (sign)

One of the principal sinkhole testing methods is ERI. Electrical resistivity imaging (ERl) is a geophysical method of determining the subsurface resistivity distribution of the soil. The resistivity measurements are made by injecting current into the ground through two current electrodes and measuring the resulting voltage difference at two potential electrodes. The equipment has a computerized switching program that automatically changes the spacing of the electrodes along with the array. The apparent resistivity is measured and processed using computer inversion software to obtain a cross-section of estimated true resistivity values. As part of the modeling process, data points with high error values may be eliminated and spikes in the data reduced. Soil types can be interpreted using known resistivity values.

Sinkhole testing method – Ground Penetrating Radar (GPR) Principles Methods

The ground-penetrating radar equipment was a RAMAC X3M manufactured by MALA GeoScience in Mala, Sweden. The setup consisted of the RAMAC monitor control unit coupled to the X3M, which was attached to a 250 MHz antenna mounted on a self-contained cart and/or a 500 MHz antenna. The cart has a calibrated measuring wheel electronically coupled to the control unit, which allows precise linear measurements to be obtained along the transect line during the fieldwork. These measurements and distances can be translated into accurate locating of subsurface features when they are identified. Ground Penetrating Radar (GPR) is also known as subsurface interface radar or impulse radar and can provide a nearly continuous profile of the subsurface conditions. High electromagnetic frequencies (typically between 40 MHz – 2.5 GHz) are transmitted from an antenna on or near the ground surface. The electromagnetic pulse is transmitted into the ground, and reflections return where there is an interface between subsurface materials of different dielectric properties. The antenna has electronics that function as a transmitter and a receiver. The reflections returned from the subsurface are relayed from the receiver to the digital control unit and are recorded on the internal memory. Depths to the reflected interfaces can be calculated using depths from boring data or estimated using known propagation rates for similar materials. GPR does not specifically identify the subsurface materials, but it does identify when a change in the subsurface strata has taken place. This can be very useful in documenting the continuity of subsurface layers, such as a confining layer for ponds and landfills, identifying potential areas of karst erosion, and locating underground pipes or other utilities.

Sinkhole testing Method – Geotechnical Test Methods

The deep borings were completed using sampling intervals required by ASTM Method D-1586 describing the Standard Penetration Test (SPT) or “split spoon” method of sampling. The penetration resistance testing and sampling were accomplished using a 2″ outside diameter sampler seated six inches into the bottom of the borehole. They advanced an additional one foot under the effort of a 140-pound hammer, faHing freely thirty inches. The number of blows required off the hammer to advance the sampler one foot into undisturbed material was noted as the blow count (N) of that particular stratum. Portions of each sample taken were classified, sealed in moisture-proof, labeled containers, and returned to our laboratories for verification of field classification.

Borings were advanced using a rotary rig, utilizing are-circulating attapulgite or bentonite drill fluid to maintain the open borehole in non-cohesive soils and to remove cuttings created by the drill bit. Upon completion, the deep borings were grouted closed following water management district regulations. The hand auger borings were completed using a bucket type of auger, which allows samples to be taken and visually classified at approximately six-inch increments. Static hand cone penetrometer data was gathered from the hand auger borings at I-foot intervals.

The penetrometer consists of a measuring instrument, a probing rod, and a cone tip. The penetrometer is pushed perpendicularly into the soil at a constant speed of approximately 2 centimeters per second by applying equal pressure on both grips. The resistance measured by the cone is read on a pressure gauge at the surface, with the maximum resistance being recorded by a dragging pointer.

No direct correlation between penetration resistance and the “N” value can be made; however, a factor of 1/4 is generally used to relate penetrometer resistance (kg/cm2). Classification of soil samples for the standard penetration test (SPT) borings and the hand auger borings were also made using the Munsell color number and common name.


31. What are the sinkhole testing methods in Florida?

Sinkhole testing method

Sinkhole testing method – What are the sinkhole testing methods in Florida? We are Unrepaired Sinkhole Buyers In Florida.


Author’s Note: It’s important to remember that not every sinkhole house has a void under it. Only a certified engineer can confirm sinkhole activity. I’ve seen houses with shifting foundations due to clay, sand, and mud classified as sinkhole houses, and the insurance company paid off the houses in full.


We Buy, Rent, and Sell Sinkhole Houses in Hillsborough, Pasco, and Pinellas Counties in Florida. 

Langee Realty Inc. Property Management Services. (813)545-5263 We Buy Unrepaired Sinkhole Houses.

Sinkhole Homeowners: Let’s explore solutions to your sinkhole house problem. We have been specializing in sinkhole properties for 15 years. We will assess your engineering report and develop a tailored action plan. Let’s discuss a safe and income-generating rental approach. My crucial objective is to prioritize the long-term viability of your property. If you prefer, we can buy your unrepaired sinkhole house. Homeowners of Tampa Bay area rental property can rest easy with Langee Realty, Inc.  We help you manage and maintain your Tampa Bay rental property. Langee Realty Inc. opened its doors in 1996. Relax, and let us take care of your property. Safety note: More homes burn down and then fall into sinkholes. Please check your smoke detectors regularly.


2. Sinkhole Florida.  3. Signs of a sinkhole.   4. Sinkhole Tampa.  5. Sinkhole house.  6. Warning signs beginning sinkhole in yard.  7. Sinkhole warning signs.  8. Sinkhole House Florida.  10. Signs of a sinkhole under your house.   19. Buy my sinkhole house fl.   23. Sell sinkhole home Florida.   26. Sinkhole foundation repair.

31. Sinkhole house worth.   32. Sinkhole house value.   33. Sinkhole house market value.   34. Sinkhole house signs.   35. Sell sinkhole.  36. Sinkhole house testing methods.  37. Sinkhole house underpinning. 38. Sinkhole house buyer.  39. Sinkhole house damage.    40. Sinkholes  41 Sinkhole house foundation repair.  42. Sinkhole compaction grouting.  43. Sinkhole house danger Florida.  44. Sinkhole house dangers. 45. Sinkhole house Hillsborough.  46. Sinkhole house Pasco.  47. Sinkhole house Clearwater Florida.  48. Sinkhole activity Florida.   49. Tampa Property Management   100. Sinkhole Site Map.

 1. Sinkhole Home Page.