PANDA® Instrumented DCP

Overview

PANDA® Dynamic Cone Penetrometer (DCP)

  • Used for compaction control and site investigation
  • Portable method for evaluating soil strength
  • Immediate repeatable results so that on-site decisions can be made straight away
  • Overcomes traditional DCP rod friction issues
  • Good for testing in challenging conditions (e.g. steeply sloping ground, remote locations, soft and marshy ground, oer-water or confined spaces).
  • Meets NF P 94-105 standard for compaction control

The PANDA® Instrumented Dynamic Cone Penetrometer (DCP) measures and displays a material’s in-situ resistance to penetration through the depth profile of the material.

We describe the PANDA® as a DCP on steroids. It has so much more capability than a conventional DCP and overcomes the safety issues. To minimise rod friction, cones larger than the diameter of the rods are used, enabling meaningful data to be collected below the 1-2m limitation of the conventional DCP. Several studies have shown that the PANDA® measurements are as accurate and reliable as the Cone Penetration Test (CPT). The benefit is that the PANDA® equipment can be used where the CPT vehicles are not suitable.

For deep or repetitive tests in the mid range of operation, a one person operated electric electric automatic hammer is available as an alternative to using the 1.7kg hammer.

For very stiff materials, the hammering column gives you more energy than with the 1.7kg manual hammer (heavier and axial energy).

PANDA®  data is downloaded to WebSprint©, the cloud based software for securely storing, processing and interpreting your geotechnical data.

WebSprint© facilitates easy collaboration across your team and gives you access to compaction control, soil investigation and correlations modules.

Compaction Control

The PANDA® is used to monitoring layer thickness, and to assess compaction homogeneity. It’s also used for layer identification. It’s designed to NF P 94-105, Soils – Investigation and Testing – Measuring Compaction Quality – Method using Variable Energy Dynamic Penetrometer – Penetrometer Calibration Principle and Method – Processing Results – Interpretation – April 2012.

You can see real time when doing the test if your material is within specification or not.

For compaction control, an integrated compaction control database for various soil types is used where the measurement of the driving depth (mm) and cone tip resistance (qd) is compared to a database based on the type of soil (soil classification), its water content and the required compaction quality (%OPN or OPM). The database of more than 2500 data points is catalogued in terms of plasticity, grain size distribution, water content, and level of compaction for both natural and artificial (crushed gravels) material types.

The related pre-calibrated reference and refusal lines, when compared to the test data, allow an assessment of the quality of the compaction to be made.

Soil Investigation

Site characterisation is unarguably the most important, but also most “difficult”, component of geo-engineering. The PANDA® probe is designed to improve the quality of site characterisation and reduce the difficulties involved.

A geological profile (database available) can be associated with the penetrogram, giving a pictorial representation of the geology and stiffness of the ground.

The typical operating range of the PANDA®  is 4-6 metres depth in soils with a cone resistance of 20-30 MPa. Exceptionally, depths of about 17m have been reached in weak soils.

Variable energy means the operator can change the force applied so more data points can be taken in weak materials, like mine tailings.

Tests orientation can be anywhere from vertical to horizontal (e.g. for tunnel walls).

The PANDA® probe can be used where Cone Penetration Test (CPT) vehicles are not suitable.

PANDA® Dynamic Cone Penetrometer (DCP) Options – Automatic Hammer, Hammering Column and Mechanical Rod Extractor

Automatic Hammer – For deep or repetitive tests, an automatic hammer is available as an alternative to using the 1.7kg hammer. The Automatic Hammer can also be operated by one person. It has a 10kg drop weight with a fixed drop height and is powered by small 240V electric generator. Penetration is at a rate of 1 blow per 3.5 seconds.

Hammering Column – The hammering column gives you more energy than with the 1.7kg manual hammer (heavier drop weight and axial energy)

  • Constant energy (free falling) or variable (by accelerated the 5kg drop hammer) 
  • Alternating hammering left hand – right hand, two hands 
  • Hammering type change possible during a single PANDA® test (manual hammering, hammering column, electric automatic hammer) 
  • Suited for stiff and very stiff materials 

Rod Extractor – Although the PANDA® Dynamic Cone Penetrometer (DCP) is supplied with a lightweight T-piece rod extractor, for most applications, this Mechanical Rod Extractor is preferable.

Advantages

  • Faster
    • Provides immediate results so that on-site decisions can be made straight away.
    • 5-10 minutes per test typical with results viewable on site
  • Accurate and Repeatable
    • By overcoming rod friction, correlates well with Cone Penetration Test (CPT)
  • Non destructive (almost)
  • Without errors
    • Equipment is instrumented (data is automatically and accurately recorded)
    • Results are machine produced (overcoming manual data recording, transposition or calculation errors and fictitious results)
    • Improved data flow and integrity using WebSprint©
  • GPS located and time stamped – know where and when every test is done
  • Visually presented results
    • Graphical representation of the data (penetrogram) on the hand held terminal, potting depth and cone tip resistance (qd) and your compaction control specification (reference and refusal lines)
  • Improved safety
    • Safe to operate (overcomes the safety issues of hand / finger crushing and back injury associated with the conventional Dynamic Cone Penetrometer (DCP)
  • Cost effective
    • One person operation: Small, portable and lightweight – 18.5kg unit – ideal to transport in hold baggage on the aeroplane for transport to remote locations
    • Thanks to its compact size and light weight, the PANDA® probe is extremely mobile and able to investigate areas with limited access or height restrictions. For example, it can be used in basements, on very steep slopes, in back yards and tunnels. No support equipment is required.

Applications

Applications for the PANDA®  Instrumented Variable Energy Dynamic Cone Penetrometer from Sol Solution include archeology, cable and pipe laying, trench work, flexible pavements, backfill, unsealed roads and mine haul roads, landfill facilities, solar farms, tunnels (e.g. testing horizontally), railway / railroad track beds and ballast (ballast fouling and formation assessment), cuttings and embankments, bridge abutments (e.g. testing horizontally and vertically), airport runway and taxiways, hard standing areas, dam construction (and mine tailings), canal building, building foundations, electricity pylons and poles, telecom masts, property sub-divisions, backyards, very sleep slopes and temporary works platforms (piling rigs and mobile crane pads). Here is the PANDA® in action in various applications, case studies and research papers on some of these applications too.

Clients include those involved in pavement construction, pavement rehabilitation, material testing, geotechnical testing and site investigation and include utilities (gas, electricity and water), road and rail authorities, councils, asset managers, mines, mobile crane and piling rig contractors, engineering and construction groups, subcontractors, geotechnical consultancies and research organisations.

Dynamic Cone Penetrometer (DCP) Calibration, Service and Spare Parts

Insitutek are proud to represent Sol Solution PANDA Dynamic Cone Penetrometers (DCP’s) in Australia, New Zealand and the Pacific Islands and provide a very high level of client support.

We offer a complete spectrum of services including after-sale technical support, servicing, repairs, and calibrations. Our service centre is also well stocked with spare parts and consumables.

 To find out more, Contact Us.

How it Works

Both the PANDA® Instrumented Variable Energy DCP and the Automatic Hammer are covered here.

  • For compaction control, an integrated compaction control database for various soil types is used where the measurement of the driving depth (mm) and cone tip resistance (qd) is compared to a database based on the type of soil (soil classification), its water content and the required compaction quality (%OPN or OPM). After entering the features of the trench, the type of the filling material used and the compaction quality required; the reference and failure will be plotted which, when compared to the test data, allow an assessment of the quality of the work to be made. The database of more than 2500 data points is catalogued in terms of plasticity, grain size distribution, water content, and level of compaction for both natural and artificial (crushed gravels) material types.
  • For soil investigation, a geological profile (database available) can be associated with the penetrogram.

The PANDA® device consists of three main components known commonly as:
(i) The Anvil
(ii) Dialogue Terminal (DT)
(iii) Central Acquisition Unit (CAU)

Dynamic Cone Penetrometer DCP PANDA Anvil being StruckThe Anvil

This part of the device is where strain gauges are built in to record strike effort from hammer blow. It is connected to the central acquisition unit by a transmission cable and a retractable measurement ribbon. The anvil sits over the rods used for ground penetration, and is repeatedly struck by the operator using a balanced hammer. Each time the anvil is hit, the relevant resistance is displayed on the Dialogue Terminal in MPa values. This is reached by strain gauges recording weight and velocity of hammer in conjunction of distance travelled through materials.

The device can be pre-set to provide an audible signal once a desired depth has been achieved and will allow the operator to cease immediately. If any object is encountered through penetration process the device will provide an audible alarm to inform the operative not to proceed further. Additional rods can be added at any time through the process, and can record readings from up to 6m in depth where conditions allow.

The Dialogue Terminal (DT)

This part of the device is where the operative can input and extract data in relation to relevant site or sounding. Data such as client information, site conditions, material, classification, and comments are easily loaded along with ability to set required maximum depth if required. Once this pre-set depth is achieved an audible warning will be heard along with a visual flashing of the screen.

This is connected to the Central Acquisitions Unit (CAU) via a serial cable which allows information to be displayed on the screen with each strike. The strike information is shown in large text format to allow the operative to clearly see the following information:

    • Strike distance achieved
    • Material resistance
    • Total depth achieved

Dynamic Cone Penetrometer DCP PANDA Setup with PredrillingA pre drilling depth can also be entered where hard surfaces have been removed as a result of a trial hole or core drilling where the CAU cannot sit on material surface. This will also allow for surface datum from where all depths are measured. Information for each sounding can be called up for display on the screen along with a table of strike results and a resistance graph known as a penetrograph. The device has a memory capable of holding hundreds of results before upload, and will maintain these results until the operative removes them.

Dynamic Cone Penetrometer DCP PANDA Central Acquisition Unit (CAU) on GroundThe Central Acquisitions Unit (CAU)

The critical information for each sounding is returned from this unit in relation to overall depth, resistance, and strike distance. Information sent from the anvil passes through this unit where it is processed and sent on to the dialogue terminal. The DT will not allow a sounding to take place unless successful connection and data input has been achieved. Each sounding usually starts with 1m of rod length which can be added to in 500mm sections. A retractable reinforced measurement ribbon is connected to the underside of the anvil which will record each strike depth and total distance travelled through penetration.

Automatic Hammer

For deep or repetitive tests, the automatic hammer alternative is available as an alternative to using the 1.7kg hammer. The Automatic Hammer can also be operated by one person. Prior to or during a test with the PANDA® probe, you can switch from manual hammering to automatic hammering. The Automatic Hammer is safe, easy to use and need a minimum amount of maintenance.

  • 10kg drop weight with fixed drop height powered by small 24V electric generator.

The PANDA® probe measures the energy exerted to the system with each blow.

Automatic Hammer Electric 10kg for PANDA DCP Close Up

Videos

NACOE Advanced methods for compaction quality control 2018

PANDA DCP Application Examples

Mechanical Rod Extractor for PANDA Dynamic Cone Penetrometer (DCP)

PANDA Probe hammering column

Automatic Hammer Electric for PANDA Dynamic Cone Penetrometer

PANDA Instrumented Dynamic Cone Penetrometer DCP – Compaction Control

Documents

Category

Topic

Publication Date

Author: Ursula Blume und Hartmut Reichenbach

Date: 2008

Erste Erfahrungen mit neuen Schnellprüfverfahren im Erdbau – Uhlig und Kudla – Technische Universität Bergakademie Freiberg – Institut für Bergbau und Spezialtiefbau – 2013

Author: Prof. Dr.-lng. Wolfram Kudla

Date: 2013

“The Panda ultralight dynamic penetrometer.” Proc 11th Euro. Conf. on Soil Mechanics and Foundation Engineering, 28th May – 1st June 1995 Copenhagen Gourves. R & Barjot. R. (1995)

Author: R & Barjot. R

Date: 28 May - 1 June 1995

Comparison Between PANDA Penetrometer Testing and Traditional Testing Methods in New Zealand – K Zamara, A Gilbert-Milne, M Larisch (Brian Perry Civil), L Wotherspoon (University of Auckland) – Sept 2018

Author: K Zamara, A Gilbert-Milne, M Larisch (Brian Perry Civil), L Wotherspoon

Date: September 2018

Estimation of compaction control, density and bearing capacity (CBR)

Correlation with other geotechnical tests including Standard penetration test (SPT), Cone Penetration Test (CPT), Pressuremeter test (PMT), Dynamic Cone Penetrometer (DCP)

Estimation of soil characterisation parameters including friction angle, undrained shear strength, shear wave velocity and deformability modulus.

Evaluating the Archaeological Potential of Urban Soil - Amélie Laurent - Proceedings of the 36th CAA Conference, Budapest, 2–6 April 2008

Author: Amélie Laurent

Date: 2–6 April 2008

The aim of the thesis was to answer historical questions about cities by assessing the informative potential of data available to archaeologists. It involved looking at the characteristics of the urban soil to understand how human activities have shaped the urban space and socio-spatial elements. More specifically, the analysis focused on assessing the thickness of the urban soil and its division into distinct functional layers in the city of Tours and sites of comparison.

Bringing together the perspectives of archaeologists and geotechnicians made it possible to develop stratification production models (maps charting the thickness of the archaeological deposit) and methods to model the heterogeneity of the deposit. Results reveal that a theoretical 100m2 grid is sufficient to understand variations in the thickness of the deposit. Vertically, the scale of analysis needed to distinguish the so-called “homogeneous” zones is roughly 10–25cm.

At the site level, an archaeological-mechanical referential frame was established for sites in Tours and Lyons. The study shows that the PANDA penetrometer can improve the characterization of the archaeological deposit. In the medium term, these advances can be furthered by developing a common referential frame for a group of sites.

On site characterization and air content evaluation of coastal soils by image analysis to estimate liquefaction risk P. Breul, Y. Haddani, R. Gourvès 2008

Author: P. Breul, Y. Haddani, R. Gourvès

Date: 2008

Coastal structures are often submitted to intense wave forcing. In some cases, structures may have stability disorders due to the constant weakening of their foundations and to momentary liquefaction of the sea bed. Studies have shown that if classical geotechnical characterization is a necessity, air content in the soil is also a key parameter for liquefaction evaluation. That is why on site air content measurement and its time variation during a tide period may provide information and help to determine a better understanding of this problem. Unfortunately, this parameter is difficult to measure during investigations.

This article presents a technique based on the use of geoendoscopy and automatic image analysis, which makes it possible to characterize coastal soils and to estimate their air content. After a description of the technique, the results obtained on laboratory tests and on a real site are presented.

PANDA Research - Roland GOURVES, Laboratoire Génie Civil Université Blaise Pascal de Clermont-Ferrand, France - 2006

Date: 2006

Research behind the PANDA and the PANDOSCOPE by the product inventor, Dr Roland Gourves.

An application of Lightweight Deflectometer Portable Impulse and Variable Energy Dynamic Penetrometer PANDA DCP devices for compliance testing of performance-based rail formation - Blanchett & Doe - ICSMGE 2022

Author: Vincent Blanchet, Douglas (Y.W.) Tun, Kelen Marczak Polli, Li-Ang Yang, Andy Doe

Date: 2021

Results of compressive strength and resilient modulus measured in situ using a Variable Energy Dynamic Penetrometer (VEDP) – PANDA DCP, Light Weight Deflectometer – Portable Impulse (LWD-PI), and Plate Load Test (PLT) and laboratory Unconfined Compressive Strength (UCS) during a full-scale trial on the Australian Rail Track Corporation (ARTC) Inland Rail project. These alternative tests reduce the level of laboratory testing effort while the near real time display of results aids in construction time frames which is of particular benefit to projects in remote locations. The methods can be combined with traditional field testing methods to develop site-specific correlations and validate geotechnical parameters assumed in the design.

Prediction of in-situ dry unit weight considering chamber boundary effects on lateritic soils using Panda penetrometer - Gansonré, Breul, Bacconnet, Benz & Gourvès (2019)

Date: 30 November 2019

This paper proposes a methodology that consists of testing Lateritic soils in-situ and in the laboratory, studying cone resistance according to compaction parameters in order to estimate the boundary effects and to propose a model to take them into account when predicting in-situ dry unit weight.

Using an artificial neural network (ANN) for the identification of soil from penetrometer data – Nicolas ROMANOWSKI Polytech Clermont Ferrand (CUST) Thesis June 2016

Author: Nicolas ROMANOWSKI

Date: June 2016

Risk Minimisation in Construction of Upstream Tailings Storage Facilities based on in-situ testing – Fourie, Palma, Villavicencio, Espinace – Proceedings of the 18th International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013

Author: Palma J.H., Villavicencio G., Espinace R.

Date: 2013

On Site Mechanical Characterization of the Ballast State – Pierre Breul & Gilles Saussine (2010)

Author: Pierre Breul, Gilles Saussine

Date: 8 December 2010

Ballast is a major railway component whose behaviour is still not sufficiently controlled. The identification of mechanisms leading to track ageing is difficult to achieve as the process occurs over several years at particle scale.

Models have been proposed to take into account ballast characteristics and provide a description of geometrical and structural modifications of ballast particles through time. To be relevant, these models must be supplied with reliable and realistic input data such as on-site density and stiffness modulus.

This article presents results that could provide these parameters, starting with on-site tests that link them with cone penetration energy.

The Panda Technology Applied to Design and Operation of Tailing Dams – Espinace, Villavicencio & Lemus – Tailings 2013

Author: Raúl Espinace and Gabriel Villavicencio, Luis Lemus

Date: 28-30 August 2013

Tailings storage facilities (TSFs) in Chile are now built using the downstream method of construction, an approach that was triggered by the failure of a number of upstream constructed facilities during or immediately after large seismic events. In Australia, the upstream method continues to be used, because of the significantly lower cost and the perceived lack of a credible seismic risk. The design of TSFs in Australia is moving towards the adoption of maximum credible earthquake (MCE) considerations, particularly for closure, where the design life is increasingly expected to be ‘in perpetuity’.

Recent research in Chile has shown the viability of using a lightweight penetrometer, the PANDA penetrometer, as a tool for rapid, inexpensive and regular in-situ determination of the state of deposited tailings. The PANDA has been calibrated against density measurements and is frequently used to estimate the relative density, which is a useful indication of liquefaction susceptibility.

This paper describes an approach for managing upstream TSFs in Australia using the PANDA penetrometer for regular in-situ testing which, when coupled with the results of laboratory compressibility measurements, can be used to predict the future state of tailings once buried to a significant depth.

Correlation between Standard Penetration Test (SPT) and PANDA DCP in Compacted Dam with Tropical Soils – Brazil – 2016

Author: Renato Resende Angelim, Caio Sales Campos, Yanko Batista Llobet, Maurício Martines Sales, Renato Pinto da Cunha

Traditionally, geotechnical projects in Brazil use the data from Standard Penetration Test (SPT). In order to enhance the accuracy and liability of the data of the soil, the PANDA 2 test was created. The light penetrometer test with variable energy is an alternative to study soil resistance and has as its main advantages the convenience, speed of the test and the automatic acquisition of the results.

The tests were carried out with the equipment on a tropical compacted soil and showed good performance, reaching depths between 8 and 9 m. The comparison of the value of “qd” from the PANDA 2 with the value of “N” from SPT, showed very good correlations as the results had similar behaviors and their comparison aims to transfer the technical experience of the SPT test to the PANDA 2 test.

Physical modelling of vibrocompaction in silica sand mixed with shells – Mollaert, Tavallali & De Schoesitter (International Marine and Dredging Consultants) & Maertens (BVBA) – Belgium – 19th ICSMGE Seoul 2017

Author: Justine Mollaert, Abbass Tavallali, Philippe De Schoesitter, Jan Maertens

Date: 2017

The available sand for the soil replacement underneath a breakwater is mixed with shells, with variable shell contents ranging up to 50%. Based on experience, the substituted sand in the foundation has to be compacted by vibrocompaction. Data from literature is not representative for the existing specific sand mixture. Therefore, in order to understand the behaviour of the sand shell mixture of the project site compacted by vibrocompaction, a series of tests in large calibration chambers combined with laboratory tests are designed and executed. The aim is to evaluate the sand shell mixture behaviour and to find practical correlations among the strength (from in-situ tests), relative density (from laboratory tests) and (in-situ) settlement due to vibrocompaction.

The strength of sand shell mixture is tested with the Panda 2 dynamic cone penetrometer. The sand is tested for different degrees of compaction and for different vibration conditions. The results show that the settlements due to vibrocompaction and the increase in resistance are not perfectly correlated. Based on the observation, it is understood that the settlements cannot be used as the only acceptance criterion for the required strength during the vibrocompaction campaign and achieved strength should also be monitored.

Methodology for the Spatial Representation of the State of Compaction in Tailings Dams – Ojeda, Zamora, Villavicencio, Espinace and Lemus – Tailings 2015

Author: Matías Ojeda, María de Los Ángeles Zamora, Gabriel Villavicencio, Raúl Espinace, and Luis Lemus

Date: 2015

An analysis of the dynamic variability cone resistance parameter (qd) is shown, which is obtained from the variable energy dynamic lightweight penetrometer test (Panda 2 ®). The assessment variability was estimated using classic statistical tools.

Estimations were performed for the qualitative characteristics as a function of the relative density (RD %), this parameter was obtained using a correlation with qdN1 (normalized dynamic cone resistance parameter). Then, the level of compaction, mechanical behavior and risk of liquefaction is determined showing weak zones. The data processing and geospatial modeling were made using the software Rockworks v.14 ®.

This work enabled a validation of the hypothesis regarding reconstruction of the internal structure of a tailings deposit, through the compaction test parameters whether quantitative (dynamic cone resistance parameter, qd) or qualitative (compaction, mechanical behavior). Weak zones and corroborating the quality of the compaction test process was performed. Furthermore post compaction control recommendations were completed.

Typical field values of penetration resistance for density and consistency of soils (Literature & Empirical based) Miguel Benz Navarrete (July 2021)

Author: Miguel Angel Benz Navarrete

Date: July 2021

Density vs PANDA Cone Resistance (Qd), Friction Angle (degrees), SPT (N), and CPT (Qc)

Consistency of cohesive (silts & clays) and intermediate soils – PANDA Cone Resistance (Qd), Strength (kPa), SPT (N), and CPT (Qc)

The PANDA Variable Energy Lightweight Dynamic Cone Penetrometer – A quick state of art – Benz-Navarrete, Breul, Bacconet and Moustan 2019

Author: Miguel Angel BENZ-NAVARRETE, Pierre BREUL, Claude BACCONET, and Philippe MOUSTAN

Estimation of compaction control, density and bearing capacity (CBR)

Correlation with other geotechnical tests including Standard penetration test (SPT), Cone Penetration Test (CPT), Pressuremeter test (PMT), Dynamic Cone Penetrometer (DCP)

Estimation of soil characterisation parameters including friction angle, undrained shear strength, shear wave velocity and deformability modulus.

Correlation between static (CPT) and dynamic variable energy (Panda) cone penetration tests – Benz-Navarrete, Breul, Arancibia and Moustan – ISC6 2020

Author: Miguel Angel Benz-Navarrete, Pierre Breul, Gabriel Villavicencio Arancibia, Philippe Moustan

PANDA Dynamic Cone Penetrometer (DCP) correlations with Cone Penetration Test (CPT)

QC & QA with Panda and GTR Soil Classification Miguel Navarrete & Haddani – Sol Solution

Author: Miguel Navarrete & Haddani

Historical background on the PANDA Instrumented DCP and the development of the Compaction Control database relating density to cone resistance Qd and standard NF P 94-105.

Mesures dynamiques lors du battage du penetrometre PANDA 2 – Miguel-Angel Benz-Navarrete – Chemical and Process Engineering. Universite Blaise Pascal – Clermont-Ferrand (2009)

Author: Miguel-Angel Benz-Navarrete

Date: 27 August 2012

Validation & Refinement of Chemical Stabilization Procededures for Pavement Subgrade comparing Dynamic Cone Penetrometer (DCP), the PANDA penetrometer, and the Portable Falling Weight Deflectometer (PFWD) – Miller, Cerato, Snethen, Holderby & Boodagh – Oklahoma Department of Transport (Oct 2011)

Author: Miller, Cerato, Snethen, Holderby & Boodagh

Date: October 2011

This study compared results of field tests and laboratory tests on chemically stabilized soil at different curing times to assess whether a relationship exists between field and laboratory measurements. The goal was to determine if a field testing method could be used to assess whether the strength and stiffness in the field are consistent with laboratory measurements used for design.

Field testing included three devices that are portable, quick, and easy to use. These devices include: the Dynamic Cone Penetrometer (DCP), the PANDA penetrometer, and the Portable Falling Weight Deflectometer (PFWD). Laboratory testing was conducted to determine the unconfined compressive strength (UCS) and resilient modulus (MR) of laboratory specimens prepared using additive contents that were similar to samples taken from field test locations.

Correlations were examined and involved basic soil measurements (mineralogical, electrical, chemical and index properties) and mechanical properties (UCS and MR), and field test results (DCP, PANDA, and PFWD). The strongest trend was observed for the PFWD – MR comparison. The trend showed that both the PFWD modulus and MR increase with increasing curing time, as expected. These observations show that development of correlations between field and laboratory test results holds promise. However, development of such correlations will require that field and laboratory tests be performed on nearly identical soils and under identical curing conditions.

Use Of Variable Energy Penetrometer And Geo-Endoscopic Imaging In Performance Assessment Of Working Platforms Constructed With Large Size Unconventional Aggregates – Hasan Kazmee, Erol Tutumluer, Younes Haddani, Miguel A. Benz Navarrete & Roland Gourves (June 2016)

Author: Hasan Ahmed Kazmee, Erol Tutumluer

Date: June 2016

Transportation agencies commonly use large size aggregates, often referred to as rock cap or aggregate subgrade, e.g., by Illinois Department of Transportation (IDOT), for stabilizing weak subgrades at wet of optimum moisture states. Adequate characterization of these large rocks is not possible in the laboratory with the use of standard tests. Accordingly, a cone penetration based strength index is the best field assessment tool since shear strength profile is closely linked to unbound aggregate or aggregate subgrade layer performance. To this end, an innovative variable energy dynamic cone penetration (DCP) device, popularly known as PANDA in France, was utilized in a recent Illinois Center for Transportation (ICT) research study involving the performance assessment of large size aggregates over soft subgrades. Twelve full scale working platform sections were constructed with six different types of virgin and recycled large size aggregate materials. Accelerated pavement testing (APT) was carried out on these sections to monitor the rutting progression with number of passes of a certain wheel load assembly. To evaluate layer properties and adequately relate them to rutting performance, PANDA tests were conducted along with traditional DCP soundings on the loading applied pavement test section centerlines.

A Geo-endoscopic probe was also used in the holes opened by the PANDA tests to identify layer interfaces and visually document subsurface moisture conditions. The PANDA and Geo-endoscopy testing has proven very beneficial in the performance assessment of the large size aggregate subgrade materials under simulated traffic loading.

This paper presents current detailed technical knowledge on the PANDA and Geo-endoscopy test equipment and highlights field results associated with the recent ICT project soundings conducted in the pavement working platform test sections.

Adequacy Of In-Place QC/QA Techniques For Evaluating Constructed Aggregate Layers Of Working Platforms And Flexible Pavements – Hasan Kazmee – Applied Research Associates, Inc., Erol Tutumluer – University of Illinois at Urbana-Champaign & Sheila Beshears – Illinois Department of Transportation (January 2017)

Author: Hasan Kazmee, Erol Tutumluer, Sheila Beshears

Date: January 2017

This paper summarizes key findings from QC/QA tests performed on full-scale pavement test sections in a recent Illinois Center for Transportation research study. The focus was to validate newly adopted Illinois DOT material specifications for large size unconventional aggregates, known as aggregate subgrade, through accelerated pavement testing. Seven representative aggregate types were used to construct test sections with aggregate subgrade and virgin and recycled capping and subbase layers. Density measurements from nuclear gauge were collected and routinely contrasted with modulus results of the lightweight deflectometer (LWD) and soil stiffness gauge (GeoGauge) from the constructed layers. Further, forensic strength assessment was carried out by dynamic cone penetrometer and variable energy PANDA penetration device. Geo-endoscopic imaging, coring and trenching were also conducted to identify depth of water table and as-constructed layer thicknesses. The PANDA penetrometer results in conjunction with geo-endoscopy proved to be effective in correlating rutting performances to QC/QA test results.

Comparative Method Report inc PANDA 2 (USA) Prof. Ilan Juran Polytechnic University (2000)

Author: Ilan Juran, Pascal Bocherel, Philippe Schaack, Alexis Rousset

Date: 19-22 September 1999

A Soil Compaction Control Technology Assessment and Demonstration

This project involved compaction control tests with three techniques generally used in the New York metropolitan area, including: The Gamma Densitometer, The Dynamic Cone Penetrometer, and the more recently developed Soil Compaction Meter. The project also included the assessment of the PANDA – a French developed soil compaction control technology. The tests were conducted in six different trenches with typical sandy backfill material compacted under different pre-selected site conditions.

Analysis of the test results demonstrated the reliability, efficiency, as well as the main advantages and limitations of each testing procedure. In particular, it was demonstrated that the PANDA provides a highly reliable tool for post-construction compaction quality control, which, due to its user-friendly software, is practically operator independent. This report briefly presents the main field test data along with site observations and summary of the main features, technical performance and cost details related to each testing procedure.

Best Practice in Compaction QA for Pavement and Subgrade Materials Year 1 Report Jeffrey Lee, David Lacey & Burk Look NACOE P60 QLD DTMR, Australia Aug 2017

Author: Jeffrey Lee, David Lacey, Burt Look

Date: 30 August 2017

Predicting grain size class from dynamic penetration test using Artificial Neural Networks – Sastre, Benz, Gourves, Breul & Bacconnet – Sol Solution & Universite Blaise Pascal France ISC5 Australia 2016

Author: C. Sastre, M. Benz & R. Gourvès, P.Breul & C.Bacconnet

Date: 2016

The Panda 2®, developed by Roland Gourvès in 1991, is a lightweight dynamic cone penetrometer. It provides the dynamic cone resistance (qd) and depth in real time with a high sampling frequency. Nevertheless it cannot take soil samples so the penetration test is called ‘blind’.

The aim of this paper is to propose an automatic methodology to predict the soil grading from the cone resistance using artificial neural networks. We have built a database based on the Panda® laboratory tests on soil samples and insitu tests next to boreholes during various geotechnical studies performed in France. Then the neural networks was used to classify the cone resistance logs according to grain size distribution of the tested soils by means of feature extraction using different signal analysis. The results show that we are able to separate 4 soil classes with 98% accuracy.

“Compaction Control with a dynamic cone penetrometer.” Laboratoire de Genie Civil, CUST, Universite Blaise-Pascal de Clermont-Ferrand, France, BP 206 63174 Aubiere – Chaigneau L, Gourves R & Boissier D (2000)

Author: Chaigneau L, Gourves R & Boissier D

Date: 28-29 February 2000

The compaction control consists in measuring the dry density and compares it with the standard Proctor density. The cone resistance in a known granular medium is directly linked to the dry density. It is the comparison between the in-situ penetrogram and a reference curve which permits the compaction. This reference curve corresponds, for a given soil and a required compaction level to the core resistance (for a passed compaction). A calibration process is necessary to establishes the reference curves. This paper sets out the compaction control method and the calibration process.

PANDA DCP Technical Description, Understanding Results & Correlations – D.D.Langton 1999

Author: D.D.Langton

Dr. Roland Gourves, principle lecturer in soil mechanics at CUST, Blaise Pascal University, Clermont-Ferrand, France has designed and developed the Panda (a lightweight hand held dynamic cone penetrometer for testing soils and materials) since 1991. It has become widely used and accepted across France, parts of central Europe and in small numbers around the world. Sinced it’s initial development the Panda has been continuously developed to be used to test the compaction of fill in earth works through software analysis as well as in site investigation. Trials have been carried out at nine sites across the UK (both working sites as well as Building Research Establishment test bed sites) to clarify the usefulness and reliability of the software analysis and correlations for use in the UK.

The PANDA lightweight penetrometer for soil investigation and monitoring material – Ground Engineering Article September 1999 D.D.Langton

Author: DD Langton

Date: September 1999

Innovative Technologies for the Control of Soil Compaction – Review of the State of the Art & Experiences in Chile – Herrera, Espinace et Palma – 15th Pan American Conference on Soil Mechanics – 2015

Author: Felipe HERRERA, Raúl ESPINACE, Juan PALMA

Date: 2015

The company Geotecnia Ambiental together with the Geotechnical Group of the Pontificia Universidad Católica de Valparaíso, with financing from INNOVA-CORFO of Chile, approached the challenge of adapting innovative, efficient, environmentally sustainable and precise technologies as alternatives in the process control of soil compaction of Chilean road infrastructure and backfill projects, through an investigation from 2012 and 2014. During the investigation more than twenty state of the art control technologies that exist on a world level were reviewed. Based on the background information dynamic lightweight penetrometer PANDA and the dynamic load plate LFG Pro were selected, of French and German engineering respectively, for use in Chile. Advantages and disadvantages for each system, as well as fields of application, output parameters and proposed methodology were all considered for use in future compaction control projects.

Railway Ballast Settlement – A New Predictive Model – Saussine, Quezada, Breul and Radjai – Proceedings of the Second International Conference on Railway Technology (2014)

Author: G. Saussine, J.C. Quezada, P. Breul and F. Radjai

Date: 2014

By means of a detailed parametric study of the settlement of ballast material per- formed on a full-scale track model, a predicting model for ballast settlement under cyclic loading has been developed. The model is based on track parameters: axle load, train speed and the initial mechanical state of ballast. A light dynamic penetrometer allows the characterization of the latter. Several loading tests, were performed, together with a characterization of the initial state of ballast close to the sleepers. The results show a settlement evolution in three stages (short, medium and long term settlement) depending on the initial conditions of the material and the intensity of the vibration.

The proposed model describes the three stages in the settlement evolution. With this model, we obtain a prediction of settlement evolution with an error less than 10% for almost all experimental data.

As a conclusion a method is proposed which has been tested on a track and which allows one to estimate the settlement of the sleepers by considering train traffic and cone penetration resistance in order to obtain an average settlement curve and a probability to reach a threshold value. This is a first step towards a general framework for the evaluation of the geometric potential degradation of railway tracks, which is a major issue for the cost reduction of maintenance operations on railway tracks.

Liquefaction potential of sand tailings dams evaluated using a probabilistic interpretation of estimated in-situ relative density – Gabriel Villavicencio Arancibia, Pierre Breul, Claude Bacconnet, Andy Fourie, Raúl Espinace (2014)

Author: Gabriel Villavicencio A., Pierre Breul, Claude Bacconnet, Andy Fourie, Raúl Espinace A.

Date: 2014

In Chile, sand tailings dams represent the most common deposits of mining residues. These structures present a potential risk in terms of mechanical instability due to their potential susceptibility to seismic liquefaction. In order to manage these risks, it is necessary to take a probabilistic approach, thus accounting for inherent variability of material properties. However, in practice, implementing such an approach is impeded by the difficulty of acquiring and managing the data to be used in the reliability calculations and is conditioned by the relevance of the probabilistic models chosen to represent this variability.
This paper proposes a method for onsite determination of the tailings relative density (DR%), and its variability, using dynamic penetration tests. This method was applied to typical Chilean sand tailings dams, and proposes a single model for all such tailings dams by associating a probability model to the variation of DR%. Finally, the validity of this approach is demonstrated by performing a reliability calculation of liquefaction potential (which is the main cause for the failure of this type of structure in this country) for a particular sands tailing dam.

Effect of Pressure, Density and Tailings Water Content on PANDA DCP Cone Resistance – Gabriel VILLAVICENCIO – Tailings 2018 Chile

Author: Gabriel Villavicencio, Gonzalo Suazo, Samuel Rojas, and Ricardo Zuñiga

Date: 2018

Dynamic Lightweight Penetrometers (DLP) are an attractive technology when prospecting tailings storage facilities due to their low cost, ease of transportation and use. One of the shortcomings of LPs is that their sounding depth is usually limited to less than 10 m. Thus, DLPs are not intended to fully replace conventional penetrometers when deep characterization of soils is required. However, they are an attractive tool for routinary control of dams. Lightweight penetrometers have been used in Chile in recent decades as a tool for monitoring the compaction degree of retaining walls in tailings dams. In addition to this, DLPs have been used in thickened tailings deposits to characterize stiffness and strength of materials. For instance, a series of correlations between DLP’s cone resistance (qd) and friction angle (𝜙) and undrained shear strength (Su) of thickened tailings have been proposed. There have also been a series of efforts to correlate qd with the tip resistance of other well documented techniques, e.g. CPT, SPT, DSPT. Nevertheless, there still exist a series of uncertainties related to the effects of tailings state parameters, e.g. water content (w %), confining pressure (𝜎′𝑣) and void ratio (e), on the resulting qd. This is experimentally explored in the present study using a pressure chamber under controlled conditions. The outcomes of this study will contribute for the rational interpretation of DLP’s results when used for the monitoring of tailings dams.

Transport Research Laboratory Assessment Summary of the PANDA CONE PENETROMETER for Compaction Testing (UK)

Assessment of natural slopes susceptible to failure in heavy rainfall based on in-situ cone resistance data – Athapaththui (University of Sri Jayewardenepura) & Tsuchida (Hiroshima University) – Japan 2016

Author: A.M.R.G. Athapaththu, Takashi Tsuchida

Date: January 2016

Slope failures are major natural disasters in Hiroshima prefecture, Japan under intense rainfall conditions. Geotechnical investigation of natural slopes is challengeable especially when natural slopes having higher gradients and access is difficult and also to estimate shear strength parameters spatially. Recently, authors have conducted a series of in-situ investigations based on the newly developed lightweight dynamic cone penetrometer to examine its applicability in analyzing the slopes covered with weathering remnants of granitic rocks. Semi-variogram analysis showed that the correlated distance of cone resistance varies with 11 to 30 m depending on the depth. A series of laboratory calibration tests based on the lightweight dynamic cone penetration tests, and direct shear tests were conducted at different void ratios and degrees of saturation. Based on the laboratory calibration test results, a method of determining void ratio, e from the data of qd was presented. Based on this, two formulas to evaluate shear strength parameters, cohesion and friction angle, were established with the cone resistance and the degree of saturation. As a whole proposed method can be successfully applied to individual slopes to determine the profile thickness, and to evaluate the shear strength parameters spatially. Based on this, hazard assessment of individual slopes can be made.

NACOE Advanced Methods for Compaction Quality Control – June 2018 Webinar – Part 1 (Webinar Slides)

Author: Jeffrey Lee, Burt Look, David Lacey

Date: June 2018

NF P 94 105 Soils – Investigation and Testing – Measuring Compaction Quality – Method using Variable Energy Dynamic Penetrometer – Penetrometer Calibration Principle and Method – Processing Results – Interpretation – April 2012 (French Standard)

Date: April 2012

Norma Chilena PANDA NCh 3261-2012 - Depositos de Relave - Control de Compactacion con Penetrometro Dynamico Ligero (Tailings Deposits - Compaction Control with Dynamic Cone Penetrometer (PANDA) - Chilean Standard NCh 3261-2012

Date: 2012

Advanced Methods for Compaction Quality Control Part 2 Question Answers

Author: Jeffrey Lee, Burt Look, David Lacey

NACOE Advanced Methods for Compaction Quality Control June 2018 webinar part 2

Author: Jeffrey Lee, Burt Look, David Lacey

Date: 6/1/2018

Advanced Methods for Compaction Quality Control

Automatic methodology to predict grain size class from dynamic penetration test using Artificial Neural Networks Sastre, Benz, Gourves, Breul & Bacconnet Sol Solution & Universite Blaise Pascal – France

Author: Sastre, Benz, Gourves, Breul & Bacconnet

Date: 2016

Part of Application of Statistical Techniques – Prof Mark Jaksa – University of Adelaide – 5th International Conference of Geotechnical and Geophysical Site Characterisation ISC5 Australia 2016

Best Practice in Compaction QA for Pavement and Subgrade Materials NACOE P60 Year 3 Report Lee, Lacey, Look & Tarr June 2020

Author: Jeffrey Lee, David Lacey, Burt Look, Kyle Tarr

Date: June 2020

Brochures

PANDA Instrumented Variable Energy DCP Brochure

PANDA Instrumented DCP hammering column brochure

PANDA DCP Rod Extractor Brochure

PANDA DCP Automatic Hammer (10kg Electric) Brochure

Blogs

We are excited to introduce the addition of a new Liquefaction Risk Estimation module in WebSprint©. Paired with our cutting-edge products, PANDA® and GRIZZLY®, this module enables you to assess the liquefaction risk of soils exposed to seismic stress. PANDA® Instrumented DCP: This cutting-edge tool provides dynamic penetrometer soundings, delivering precise data crucial for seismic risk evaluations. GRIZZLY® […]

In an industry set with challenges of staff and skills shortages, and unrealistically low pricing for some traditional test methods, our approach as an industry needs to change. What we are measuring and the time between tests being done and results delivered back to the construction team are both important considerations. Recently, I sat down […]

Learn from the best at Sol Solution about the WebSprint Software for the PANDA Instrumented DCP (VEDP), GRIZZLY Dynamic Probing Super Heavy (DPSH), eKODIAK Multi Mass Automated DCP and others. Here is the agenda for the session: Insitutek welcome – 5 min WebSprint Software presentation by Sol Solution – 45-50min DataSprint presentation Integration PANDA®, GRIZZLY®, eKODIAK®, deflectometers, others tests data Compaction control and […]

Insitu Test recently completed PANDOSCOPE® training for our WA Implementation Partners, STATS Australia and 4DGeotechnics.  The PANDOSCOPE® is a coupling of the PANDA® Instrumented Dynamic Cone Penetrometer (DCP) (tip resistance vs depth profile) and Geoendoscopy (down the hole imagery).   For rail applications, the PANDOSCOPE® is used as a non-destructive rail track ballast and formation condition assessment method when planning track maintenance and […]

There is nothing like jumping in at the deep end!  With buy in from Fortescue Metals Group, BHP and Rio Tinto, we brought together our supply partner, Sol Solution from France, and the extreme conditions of deep fouled ballast and the Pilbara climate to test to see how the PANDOSCOPE® would operate. Suffice to say, the outcomes were very positive and we […]

We always like getting involved in helping our clients solve difficult problems. This was on one of the world’s largest grid-connected PV power plants.   Thousands of solar PV tracking panels across several hectares were built in NSW as a solar farm. However the project had been rushed to be finished.  After noticing some of the solar panels were […]

We find our clients are increasingly demanding more accurate and more representative results that provide better insight on what’s going on below the surface when they are designing or constructing projects so they can make well-informed decisions in a timely manner. Having worked for nearly 15 years at the forward edge of field-testing methods that […]

The acceptance of earthwork and unbound pavement construction in Australia currently relies on density testing and CBRs for Quality Assurance (QA). Though its National Asset Centre of Excellence (NACoE) research program, Queensland Main Roads has sponsored an ARRB research project to update test methods acceptable for use for QA of pavement and subgrade materials including […]

Credentials

PANDA® Dynamic Cone Penetrometer

Military Army RAAF PANDA DCP Sol SolutionMore than 3000 PANDA® Probe units have been distributed to:

  • Asset owners
  • Soil investigation and ground investigation companies
  • Geotechnical engineering consultancies
  • Government authorities including road, rail and airport authorities and councils
  • Construction companies
  • Research institutions

The PANDA® has become widely used and accepted across Europe and internationally from Mexico to the USA and from Japan to Korea. To find out more, Contact Us.

The PANDA® is produced under licence by Sol Solution,  Les Portes de Riom Nord – BP 178 – 63204 RIOM Cedex FRANCE  www.sol-solution.com

Sol Solution spending more than 10% of their budget annually on research and development.

The PANDA® was designed and developed by Dr. Roland Gourves, the Principal Lecturer in soil mechanics at CUST, Blaise Pascal University, Clermont-Ferrand, France in 1991.

PANDA Probe PANDA Instrumented Dynamic Cone Penetrometer DCP

FAQ

Does the PANDA® account for any dynamic effects in the test results?

The dynamic effects have not been considered for the PANDA®. Nevertheless, these effects are reduced to a minimum as the speed of deformation is very low. The advantage of the PANDA® sounding (compared to pile driving) is that you can reduce the hammering speed (and force) when you perform a sounding on a “weak” soil.

Is a continuous measurement of force and penetration is made?

Yes, the force and penetration is measured with each blow. This continuous measurement is what the user sees on the Dialogue Terminal and on the software: it is the penetrogram. The user can also check the data table on the dialog terminal or through the software. They will see, for every impact, the driving depth and the cone resistance per blow.

The bearing capacity (qu) is calculated from the dynamic cone resistance (qd) as follows:

For soil investigation, the bearing capacity (qu) is calculated from the dynamic cone resistance (qd) as follows:

Lateral friction is avoided with ‘lost’ cones of area 4 or 10 cm².The maximum resistance you can test with the PANDA® is about 30 MPa. Note that 1 Mpa = 1000 kpa = 10 bars = 0,1 KN/cm²

We want to use the PANDA® to test crane pad locations and we have calculated that the ground must withstand 100 Tonnes / Square Metre.

How does this relate to the PANDA® results?

100 t/m² = 100000 kg/m² = 1 MPa = 10 bars : that is the pressure the crane gives to the soil under the crane foundation (pads)(insulated foundations).

So the soil must be able to “retain” 1 MPa under the foundation. This must be the minimum bearing capacity qu of the soil under the crane foundation.

And with the following correlation qu (in bar) = qd (panda in MPa) x 10 / (12 to 15) – let’s take 15 for safety and use only the 4 cm² PANDA® lost cone in order to avoid the lateral friction around the rods.

In this case the minimum qd panda® tip resistance would be : qd (in MPa) = qu x 15 /10 = 1 MPa x 15/10 = 1.5 MPa

So you should need a qd PANDA® cone resistance (qd) minimum of 1.5 MPa for an enough depth of 2 times the width of the foundation (insulated foundations). For example, with a foundation of 1m x 1m, you should need 1.5 MPa with the PANDA® for 2 meters under the foundation.

Test Hole Spacing – at the university which makes the calibration of the PANDA®, they consider that you can make tests with the PANDA® with 15 cm between each test hole. 20 cm is a conservative value.

What different names isPANDA® Variable Energy Light Weight Dynamic Cone Penetrometer known as?

PANDA® 2 Ultra Light Dynamic Cone Penetrometer
PANDA® 2
PANDA® 2
PANDA®
PANDA® Probe
Dynamic Probe
Cone Penetrometer
Ultra Light Dynamic Cone Penetrometer
Dynamic Cone Penetrometer
DCP
Penetrometer
Variable Energy DCP
PANDA® 2 Variable Energy Ultra-Light Weight Dynamic Cone Penetrometer

What is the Maximum Depth that the PANDA® can reach?

It depends of the resistance of soils, but the PANDA® can be made to reach 5 to 7 m in classicals soils (<10 MPa). However, in certain cases, it will be only a few centimeters (e.g. rocks). The softer the soil, the deeper you can go. In exceptional circumstances, we have known tests done to 17 meters. When doing soil investigation using the PANDA® (with the 4 cm² lost cone), the main reason to stop a PANDA® test is because of lateral friction on the rods. If you cannot turn the rod with your hand, it means that the lateral friction becomes important and then the value qd in MPa is not only the resistance under the cone (which is the principle of the DCP), but the resistance under the cone added with the resistance along the rods. The qd value will be higher than it should be and we are not able to quantify this error. The operator has to take this into account. The lateral friction will appear normally more rapidly with sandy soils than with silty soils or clayed soils. Sandy soils will collapse more easily into the hole (and generate lateral friction on the rods) than clayed soils. This can be overcome with a 20mm PVC plastic pipe sleeve following the sacrificial cone (larger diameter than the rod) as it is driven into the ground.

What is the relationship between qc and qd?

qc is cone resistance measured with the Cone Penetration Test (CPT) where a cone is pushed into the ground at a constant speed (e.g. 2cm/second). It’s also know as the static cone penetration test. qd is cone resistance but measured dynamically and is known as the Dynamic Cone Penetrometer (DCP). To do a comparative test, the geology should be the same so test probes should be done approx 30-40cm apart. A minimum of three comparative tests would be required. When comparing qc and qd, care needs to be taken with sandy soils because of lateral friction / skin friction on the rods.

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Insitutek Blogs

We find clients are often looking for ways to improve geotechnical testing outcomes and do it more efficiently at the same time. This drives their buying decision making. Australian Soil and Concrete Testing (ASCT) was a case in point when they were searching for Plate Load Test equipment for their upcoming Collector Wind Farm project. Some of the things that motivated them include: […]

We are excited to introduce the addition of a new Liquefaction Risk Estimation module in WebSprint©. Paired with our cutting-edge products, PANDA® and GRIZZLY®, this module enables you to assess the liquefaction risk of soils exposed to seismic stress. PANDA® Instrumented DCP: This cutting-edge tool provides dynamic penetrometer soundings, delivering precise data crucial for seismic risk evaluations. GRIZZLY® […]

The Australian Geomechanics Society is gearing up for a series of geotechnical events across VIC, WA, NSW, and SA-NT. We are thrilled to inform you that we will be sponsoring and attending these exciting geotechnical events, and we would love for you to join us. It’s a fantastic opportunity to catch up, explore our booth (VIC), and stay informed about […]