Dynamic Cone Penetrometer Tests Research Articles

Presenting a CBR Estimation Model and Compaction Characteristics of Base Layer of Pavement Using a Dynamic Cone Penetrometer (DCP) Test

Presenting a CBR Estimation Model and Compaction Characteristics of Base Layer of Pavement Using a Dynamic Cone Penetrometer (DCP) Test

A Case Study of Pavement Foundation Support and Drainage Evaluations of Damaged Urban Cement Concrete Roads

Surface cracks and joint deteriorations are typical premature failures of urban cement concrete pavement. However, traffic loads on the urban pavement are much lower than those on highways. Limited research has been conducted to investigate the causes of accelerated damage in urban cement concrete roads. To investigate the foundation issues that may cause the accelerated damage of urban cement concrete pavements, in this study, field evaluations were conducted to assess pavement foundation support and drainage conditions. Field visual inspections, Ground Penetrating Radar (GPR) survey, Dynamic Cone Penetrometer (DCP) test, and the Core-Hole Permeameter (CHP) test were performed. In urban residential areas with inadequate subgrade bearing capacity, cement concrete pavements are prone to early damage. Foundations with a higher content of coarse particles exhibit a higher CBR value, which can extend the service life of the pavement. The compaction of foundation materials near sewer pipelines and manholes is insufficient, leading to non-uniform support conditions. Moreover, the permeability of the foundation material can influence the service life of pavement surface structures. Foundation materials with fewer fine particles enhance drainage performance, contributing to a longer service life for PCC pavements. In areas with inadequate drainage, water accumulation reduces the bearing capacity of the foundation, thereby accelerating pavement deterioration. The poor bearing capacity and drainage conditions of the foundation lead to cavities between the surface layer and foundation material thus yielding stress concentrations on the pavement surface, which cause the formation of pavement surface cracks.

Study on performance of geocell-reinforced red clay subgrade

Three comparative treatment plans are used to study the effect of red clay subgrade reinforced with geocell. Multiple subgrade test methods including Benkelman beam, portable falling weight deflectometer, dynamic cone penetrometer and standard vehicle load tests are adopted in the field tests. Test results show that the application of geocell in red clay subgrade can enhance the overall stiffness and strength of the subgrade. The mechanism of geocell in the subgrade is studied. Geocell can provide added confinement to the subgrade soil. Compared with the red clay subgrade without geocell reinforcement, for the red clay subgrade reinforced with 0.1 m-high geocell and 0.05 m-high geocell, the rebound modulus increases by 65% and 33%, the dynamic modulus increases by 69% and 38% and the penetration decreases by 51.7% and 40.4%, respectively. A hard shell layer is formed in the subgrade when it is reinforced with geocell. The geocell-reinforced layer mainly plays the role of stress diffusion. It not only can reduce the additional stress in the subgrade but can also diminish the influence of the depth of the vehicle load.

Hammer weight and dropping height effects on dynamic response in densely-packed geo-materials

This study aims to investigate the dynamic cone penetration index (DCPI) and dynamic responses during instrumented dynamic cone penetration test at fixed-end condition (e.g., dense layer). Several types of hammer weights and heights at fixed potential energy (45.13 N∙m) is applied on the instrumented dynamic cone penetrometer (IDCP) tests. Test results show that the instrumented dynamic cone penetration index (IDCPI) is proportional to the DCPI with various gradients lower than 1.0 due to the influence of hammer weight on drivability. Dynamic responses change with respect to the end boundary condition (e.g., dense or loose layer) and location at the head or tip. In addition, the transferred energy varies with respect to the end boundary condition, location, hammer weight and height. For layer characterization, the end boundary condition should be primarily considered as well as hammer weight and height regarding drivability.

Effect of Composite Portland Cement for Subgrade Stabilization and the Effect on Unsoaked CBR Value

Soil is a material that has an essential role in construction. Soils that have low bearing capacity require soil improvement. One method of soil improvement is soil stabilization using composite portland cement. Based on the results of the Dynamic Cone Penetrometer (DCP) test, the location in this study, namely Cibingbin village, Pandeglang Regency, has a bearing capacity of 2.67%, meaning that the soil at this location needs to be repaired. This study aimed to determine the effect of portland cement on physical properties and unsoaked CBR values. Variations of portland cement used were 0%, 4%, 6%, and 8%, with curing times of 0 days and seven days. The results showed that based on the unified soil classification system (USCS), the soil classification was in the CH category (inorganic clay with high plasticity, fat clay) and the maximum CBR value was obtained at 8% Portland cement variety at seven days curing time, namely 13.23%.

A Case Study on Distresses of Concrete Pavements Supported on a Retaining Wall

Embankments and retaining walls are integral parts of the bridge system and provide a smooth transition from lower elevations (i.e., roadways) to higher elevations (i.e., bridge decks). Performances of pavement structures supported on embankments or retaining walls are directly related to their conditions. This paper presents a comprehensive case study of the evaluation of pavement structures supported on an in-service mechanically stabilized earth (MSE) wall that showed significant distresses, such as lane separation, faulting, lane settlement, and tilting of the MSE wall. The conditions of the pavement structures were evaluated via visual observations, falling weight deflectometer (FWD) tests, and coring through pavement structures. The conditions of the MSE wall were evaluated through dynamic cone penetrometer (DCP) tests, cone penetration tests (CPTs), LiDAR surveys, and soil borings. Detailed analysis of the data obtained in this study provides valuable insights into potential distress mechanisms.

Strength and stiffness characterizations of geo-materials composing unpaved roads using LFWD, DCP, and CDP tests

To assess the condition of the geomaterials composing unpaved roads subjected to cyclic wheel loads by moving vehicles, it is necessary to evaluate the variations in mechanical properties with depth. In this study, a crosshole-type dynamic cone penetrometer (CDP) was applied to characterize the stiffness of unpaved soil along its depth. In addition, light falling weight deflectometer (LFWD) and dynamic cone penetrometer (DCP) tests were conducted for a comparative analysis. The LFWD, DCP, and CDP tests were conducted on a newly constructed unpaved road after the application of 0, 200, and 400 cycles of wheel loads by a moving vehicle. From the experimental results, the strength and stiffness properties such as Evd, NDCP, and Vs, were obtained, and their incremental ratios were investigated according to the number of cyclic wheel loads. In addition, the improved relationships between Evd, NDCP, and Vs were constructed considering the strain influence factors with depth. This study demonstrates that CDP can be an efficient testing method to profile the stiffness of unpaved roads, and the relationships considering the strain influence factors may be used effectively for reasonably estimating the engineering properties.

Effects of Physical and Mechanical Properties of Soft Soil on Subgrades Performances in Lubuk Bayas Village, Serdang Bedagai Regency

Generally, the existence of soft soil in Indonesia will be a problem in the construction of highway construction. One factor that influences and needs to be known in road construction is the characteristics of the subgrade where the pavement construction will be placed on it. Poor soil characteristics can cause bumpy road surfaces, cracks, or other road damage. Therefore, before carrying out a soil improvement, it is necessary to know its characteristics through the physical and mechanical properties of the subgrade. This research was conducted in Lubuk Bayas Village, Serdang Bedagai Regency, North Sumatra Province. Tests of physical properties in this study include sieve analysis, water content, specific gravity, plasticity limit test, and liquid limit test. The soil shear strength test and California Bearing Ratio (CBR) test were carried out to test the mechanical properties using a Dynamic Cone Penetrometer (DCP). From the results of testing the physical properties of the soil, it was found that Samples 1, 2, and 3 were fine-grained soils with the percentage of soil passing the No.200 sieve greater than 50%. The USCS classification system shows that samples 1 and 2 of the soil are in the Lean Clay (CL) group, while sample 3 is in the Fat Clay (CH) group. Samples 1, 2, and 3 include soils with high plasticity because the PI value is >17. The results of testing the mechanical properties of the soil Sample 1 obtained the value of c = 0.1299 kg/cm2 and Ø = 13.2°, in Sample 2 obtained the value of c = 0.1075 kg/cm2 and the value of Ø = 11.2° and in Sample 3 obtained the value of c = 0.1275 kg/cm2 and the value of Ø = 11.9°. DCP testing on samples 1, 2 and 3 obtained CBR values of 5.35%, 4.73% and 3.15%. From the CBR results, it can be seen that the soil in this location has a low soil bearing capacity, so if it is to be used as a subgrade layer, it will be necessary to repair the soil first so that structural damage does not occur in the future. Soil improvement can be made by stabilizing the soil using natural materials to maintain environmental sustainability. Natural materials that can be used include sand with certain gradations, stone ash, palm shell ash, and various other natural materials.

Analysis of Physical and Mechanical Soil Properties Determined Using Interpretations of Dilatometric Test (DMT) and Cone Penetration Test (CPT) Methods

Road design is a complex, time-consuming, and very responsible process. To develop a high-quality and viable road project, it is very important to start with an accurate geological survey in order to define the best road layout. Moreover, the geotechnical characterisation of foundation soils and construction materials as well as the analysis and assessment of geotechnical works are mandatory. Laboratory and in situ investigations are complementary and should be carried out by defining a cost-effective investigation campaign. Most often, Dynamic Cone Penetrometer (DCP) or Cone (static) Penetration Test (CPT) are performed because they are economic and quick. In addition, it is also possible to perform the Marchetti Dilatometer Test (DMT). From the obtained test results, the data are interpreted by determining the properties of the soil layers. Although all probing methods are similar, each of them gives slightly different results. The aim of this study is to analyse and compare the results of the probing test, to determine the difference between the obtained data and to find out how the obtained results affect the development of constructive solutions from the safety and economic point of view.

Improving bearing capacity using tire-derived-geo-cylinder – a haul road case study in Jalan Sikar Penajam Paser

This paper showcases a potential solution to improve soil bearing capacity using tire-derived-geo-cylinder (TDGC). TDGC uses used tires to provide confining pressure and tensile strength, hence improving the soil’s bearing capacity. The solution is applied for a haul road project on Jalan Sikar Penajam Paser. The site is frequently passed by large vehicles such as large trucks for the transportation of wooden logs and other heavy equipment. The tires used for TDGC are used tires of type LT245/75R16, which has a standard rim of 16 mm, a tire width of 248 mm, and an overall diameter of 780 mm. This category of tires has a load index of 1250-1600 kg. The load index is the value representing the tire's capacity to withstand load. The improvement in bearing capacity is evaluated using dynamic cone penetrometer (DCP) tests. In addition, the DCP tests were also used to interpret the Californian Bearing Ratio (CBR) values. The results show that without TDGC, the average CBR value is only 4.7%. In contrast, with TDGC, the average CBR increased to 17.2%, an increase of 265%. The CBR value obtained with TDGC places the soil into fair category for Subbase course. The average bearing capacity value obtained before TDGC was about 75 kN/m2 and with TDGC, the soil experienced a significant increase in bearing capacity value to 245 kN/m2. The increase of bearing capacity and CBR value from application of TDGC are due to the combination of the tires and stone fill. The tires provide tensile strength to resist lateral soil pressure as well as increased confining pressure, hence increasing the compressive strength.

Laboratory and Field Evaluation of Stabilized Fly Ash as an Alternative Material for Sustainable Pavements

Thermal power plants in India produce a large quantity of fly ash, which is harmful to the environment. Underutilization of fly ash and the scarcity of natural minerals have created the need for an unusual construction strategy to prevent huge waste dumps on valuable land and to preserve fast-depleting resources. A study was conducted to determine the efficacy of lime-stabilized fly ash blended with quarry fines as flexible pavement subbase materials. The laboratory investigations were conducted to determine compaction characteristics, unconfined compressive strength, California bearing ratio (CBR), and durability to obtain the optimal quarry fines, fly ash, and lime (QFL) mix. The durability of QFL mixes was studied using 12 wetting–drying cycles. Using the strength and durability criteria specified by the Indian Road Congress, the optimum mix proportion of 40Q:60F+3L was determined. Pavement analyses were performed using the IITPAVE program. The QFL mix was observed to be superior to conventional granular subbase (GSB) layer material in terms of service life and cost-effectiveness. A field investigation was carried out on trial test sections constructed using the optimum QFL mix and GSB in the subbase layer of pavement. Field dry density and dynamic cone penetrometer (DCP) tests were performed on the compacted subgrade and subbase layers to assess the desired quality assurance in the construction of test sections. The early structural performance assessment of pavement sections using a falling weight deflectometer (FWD) test indicated that QFL could effectively replace conventional GSB.

Lime Treatment of Lake Texcoco Clays with Some Insights on the Application of Deep Mixing Columns

The soils across Lake Texcoco (LT) basin are notorious for the presence of highly compressible salt-affected lacustrine clays. The geological formation of the area accompanied by the unmonitored flow of water from Mexico City region has resulted in a unique sodium-rich clay that is highly plastic (plasticity index~200), and impermeable ( k~1.5 × 10−9 m/s) and possesses low compressive strength (unconfined compressive strength < 10 kPa). Over the last few decades, the entire basin has settled at an average of 13.2 cm per year and will continue further with increased loads as a result of rapid urbanization. In planning a solid foundation for the airport, as well as developing the surrounding area, trial sections were built to analyze the effect of quicklime (CaO) on the natural clay s physical, chemical, and engineering properties through laboratory testing. The lab-scale investigations were accompanied with field measurements using the variable energy dynamic cone penetrometer (DCP) and plate load tests. Additionally, a numerical analysis of the effect of deep mixed columns (DMC) to reduce consolidation settlement was performed. The numerical analysis comprised of various DMC stabilizers, loading pressures, column lengths, and area replacement ratios. DMC lengths were observed to be the most dominant parameter to reduce consolidation settlements. Settlement reduction was more sensitive to the area replacement ratio for end-bearing columns, and to the loading pressures for floating columns. Based on the stabilizers evaluated, a combination lime and Portland cement performed the best across all loading pressures and column lengths. Other stabilizer combinations also had a remarkable effect on limiting the consolidation settlement.

Application of automated cone penetrometer for railway investigation using correlations with DCPI and deflection modulus

Portable in-situ devices have been used for characterizing low accessible field, such as the railway subgrade. In this study, the automated cone penetrometer (ACP) was designed for the application on the railway subgrade. ACP is composed of the cone tip, driving rod, and hydraulic hammer system. The hydraulic motor lifts and drops the 294.3 N hammer from a height of 200 mm such that the potential energy of 58.9 N m impacts the driving rod. The N-value (NACP) from the ACP test was compared with the dynamic cone penetration index (DCPI) from the dynamic cone penetrometer (DCP) test. The test results show that the NACP and DCPI profiles show opposite trend owing to the inverse concept of the unit. From the correlation of DCPI and NACP, the limitation of DCPI reveals owing the minimum manually measured value of 1 mm/blow. Additionally, the evaluation of the deflection modulus (EFWD) using NACP is more efficient than that using DCPI. Based on the result of this study, we suggest that ACP can be used for strength and stiffness evaluation of railway subgrade rapidly and reliably.

Development of Prediction Models for Performance of Flexible Pavements in Kansas with Emphasis on the Effects of Subgrade and Unbound Layers

This study resulted from the need for better consideration of subgrade and unbound layers on the performance of flexible pavements in Kansas. Thus, the main objective was to develop pavement performance prediction models with emphasis on the effects of subgrade and unbound layers. To this end, pavement distress data, which were collected over several years across the state of Kansas, including rutting, fatigue cracking, transverse cracking, roughness and core analysis, served as the input data into statistical models. The effects of subgrade and unbound layers were represented by the corresponding results of dynamic cone penetrometer (DCP) tests and thickness of the unbound layer. In addition, traffic volume was represented by average annual daily truck traffic (AADTT). Multiple statistical analyses identified positive correlations of dynamic cone penetration index (DPI) and rate of total rutting, and DPI and percent of good core. Negative correlation was discovered between DPI and fatigue cracking code one, and DPI and percent of poor core. AADTT was positively correlated with transverse cracking codes one and two while it had no correlation with transverse cracking code zero. Thickness of the unbound layer was negatively correlated with pavement roughness and percent of poor core, while it was positively correlated with the percent of good core. Finally, the recommendation for minimum acceptable value of California bearing ratio (CBR) was provided based on the correlation between DPI and rate of change of rutting code. The recommendation enables the selection of a CBR value based on the number of years required for unit increase in the rutting code.

Long-Term Performance of Flexible Pavements Constructed on Recycled Base Layers

There has been an increased interest in using reclaimed asphalt pavement (RAP) aggregates as a base course in Wisconsin for the offered economic and environmental benefits. Laboratory studies showed that RAP can have resilient modulus values higher than typical natural aggregates, and can also have higher durability, especially in freeze–thaw cycles. However, it is also recognized that RAP exhibits temperature sensitivity and larger permanent deformations than natural aggregates. How these characteristics manifest themselves in the northern U.S. climates can only be assessed by long-term observation of field performance. Wisconsin Department of Transportation (WisDOT) has been using RAP as a base course for over 30 years. The qualitative assessment of WisDOT roads constructed with RAP showed they are performing adequately. However, this impression has not yet been verified quantitatively. This paper presents a quantitative assessment and comparisons for field performance of pavement test sections constructed with RAP and natural crushed aggregate (CA) base course layers in Wisconsin. The performance was evaluated using pavement distress surveys of roadways containing RAP and CA, falling weight deflectometer (FWD), dynamic cone penetrometer (DCP) tests, and analysis of WisDOT’s available data. Based on the field evaluation, the performance of the hot mix asphalt (HMA) pavements with RAP was found adequate and comparable to those with CA base course layers. A recommendation was given that WisDOT shall continue the practice of using RAP in base course layers of HMA pavements, given proper quality checks for materials, and proper quality control/quality assurance measures being applied during construction.

3D response surface modeling based in-situ assessment of physico-mechanical characteristics of alluvial soils using dynamic cone penetrometer

Dynamic cone penetrometer (DCP) is the quickest and cheapest in-situ probing apparatus to estimate the soil stiffness; however, insufficient correlations are available to directly assess various physico-mechanical characteristics of natural alluvial soils using DCP. The key purpose of this study is to statistically equate the in-situ DCP test outcomes to different physico-mechanical characteristics of alluvial soils. For this purpose, in-situ DCP tests were performed at 26 different locations in the Indus plane, and corresponding undisturbed specimens were collected for laboratory testing. Various physico-mechanical characteristics of soil i.e., natural water content (wn), natural dry unit weight (γd), unconfined compressive strength (qu), deformation modulus (E50), strain at failure (εf), natural void ratio (en) and California bearing ratio (CBR) were determined in the laboratory. Initially, the regression-based models were established for γd, qu, E50, εf, en, and CBR using dynamic cone penetrometer index (DCPI) as a solitary predictor. Afterward, predictive models of the aforementioned parameters were developed based on wn integrated DCPI by quantifying the best-fit trend line and three-dimensional (3D) response surface among pertinent dependent and independent variables. In addition, it is found that the models developed using 3D response surface modeling hold 8.2–42.4% lesser error than the regression-based models developed in the current study. Moreover, results show that the DCP based assessment of soil is influenced by wn and independent of consistency limits and soil type of the alluvial soils.

Prediction of CBR using dynamic cone penetrometer index

Nowadays, construction of new roads and upgradation of existing roads are booming as a part of infrastructural development in India. Subgrade strength plays an important role in the design and construction of pavement. California bearing ratio (CBR) test is used to measure the strength of subgrade and most of the highway agencies design the pavement section using CBR value of the subgrade. The conduction of CBR test consumes more effort and time as it involves soil sampling, preparation of soil specimens, soaking for 96 h and testing. Also, the laboratory assessment of CBR does not simulate the in-situ soil properties (mainly moisture and density) and the laboratory CBR sometimes may be higher than the CBR of the soil under in-situ condition as compaction is carried out in a confined rigid mould. In this study, dynamic cone penetrometer (DCP) index is used to predict the subgrade CBR values. A total of eight soil samples were collected from two different sites and the various engineering properties are determined. To know the effect of density, moisture content, fines content and CBR on the dynamic cone penetration index (DCPI), a series of laboratory compaction tests, CBR tests and DCP tests are conducted. The available correlations are verified for their predictability of CBR values and the correlations suitable for the local soils are recommended.

Evaluation of soil replacement and cement grout injection in soil settlement

This paper discusses the process of original soil stabilization in Trans Sumatra Bakauheni-Terbanggi Besar Toll Road Project Package 2 Sidomulyo-Kotabaru. The soil replacement process was conducted at approximately 24 kilometres along the toll’s main road. The original soil bearing capacity analysis stage was by performing a Dynamic Cone Penetrometer (DCP) and Sondir test to analyze the deep of hard soil. A soil replacement was carried out to replace the original soil with soil that has appropriate specification. the piling up process was conducted in stages, which has Sandstone in such of the layer. The research done about the landfill sample was retaken and collected at 68 points. The stockpile soil samples collection was then followed by the analysis which was conducted in the laboratory to find the soil bearing capacity. There are 4 types of bearing capacity parameters analyzed, namely specific gravity, water content, aggregate analysis (Sieve Analysis), and consistency limit (Atterberg Limit). Referring to it, then there was the classification of soil types according to AASHTO M145 & Casagrande Soil Classification System. A point that has settlement after soil replacement is STA 52+000. So, there need to add soil stabilization, that is cement grout injection. Researchers analyzed the soil settlement by interpretation method. Results showed that soil replacement and cement grout injection could decrease a soil settlement by about 15.07 cm to become 0.93 cm.

Comparison of California Bearing Ratio (CBR) Value Based on Cone Penetration Test (CPT) and Dynamic Cone Penetrometer (DCP)

In civil engineering, land is important because as a place for building infrastructure to be built, so that the building infrastructure on it is stable, adequate carrying capacity is needed. The amount of soil bearing capacity can be determined in several ways, including the California Bearing Ratio (CBR) Field Test, Cone Penetration Test (CPT) and Dynamic Cone Penetrometer (DCP). The CBR and DCP tests are often used to determine the level of surface soil density on road structures, while CPT is usually used to determine the hard soil layer on the building structure. However, in certain situations Sondir and DCP data are often used to predict the CBR value, because the test is quite practical and efficient compared to the CBR test. CBR testing requires heavy equipment which in most small-scale projects is not available. In this study, we compared the CBR value based on the data obtained from the Sondir and DCP tests. Data collection was carried out in Surakarta and its surroundings. Based on the test results, the CBR value generated from the DCP test tends to be smaller than that from the CPT test with a ratio of 0.62: 1. This study resulted in the relationship between CBR values from the results of the CPT and DCP tests shown in the following equation: CBR (DCP) % = 0.2552 CBR(CPT) + 2.6306 and CBR (DCP) % = 0.617 CBR(CPT).

Application of the dynamic cone penetrometer test for determining the geotechnical characteristics of marl soils treated by lime

Quantitative estimation of mechanical characteristics of soils and determination of their behavior using in-situ experiments have always been one of the main concerns of geotechnical engineers. So far, various methods have been introduced to achieve this goal, among which the Dynamic Cone Penetrometer (DCP) test has become more popular as one of the most accurate and efficient methods. Therefore, in this study, an attempt was made to examine the correlation between different soil parameters by performing DCP test along with a series of conventional tests including Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) tests on marl soil samples containing 2, 5, 8% lime at 1, 7 and 15 curing days. Furthermore, since the subgrade reaction coefficient (Ks) is needed in the design of pavements and their underlying materials, Plate Load Test (PLT) was performed to determine Ks. The results showed that the addition of lime up to 5% increased UCS, CBR and Ks and decreased dynamic penetrometer index (DPI) of marl soil samples. Further addition of lime had a negative effect on the mechanical characteristics of the samples. Moreover, using the equations obtained from the correlations in this study, strength characteristics and subgrade reaction coefficient of the stabilized marl soil can be estimated by knowing the DPI of the samples. The results of this study showed that the use of the DCP test as a cheap and easy-to-use method can provide a comprehensive view of soil behavior in civil engineering projects with an acceptable coefficient of determination to geotechnical engineers.