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The strength of the subgrade is an important consideration when designing working platforms for pavement structures. Furthermore, dynamic cone penetration tests are used to characterize the strength of the subgrade because determining the CBR value in the field requires the use of the equipment and is time-consuming. Instead, the CBR value of subgrade in the field can be predicted using other soil support tests, specifically the dynamic cone penetrometer index (DCPI), which has advanced as the most versatile rapid, in situ assessment device currently available for use in determining subgrade strength. The correlation of the DCPT index to CBR and its application in pavement performance assessment make it an appealing alternative to more expensive and time-consuming approaches. Internal friction angle and California bearing ratio values can be determined with great accuracy using correlation data of the dynamic cone resistance obtained from the instrumented DCP. This research implies that employing an instrumented DCP to determine subgrade strength could be a promising in-situ testing method. Therefore, field DCP tests were performed at six sites, each one kilometer away from the other, and a sample was taken for the laboratory's tests of the California bearing ratio and the shear test. The results of the laboratory tests were close compared to the results of the DCP test, and therefore this examination is considered faster and easier to know the characteristics of the soil. [ABSTRACT FROM AUTHOR]

This experimental study develops a methodology to find the correlation between the California Bearing Ratio (CBR) and the Dynamic Cone of Penetration (DCP). The physical (particle size, Atterberg Limits, moisture, and density) and mechanical (CBR and DCP) properties were determined through laboratory tests. The soil utilized for the tests belongs to the subgrade and sub-base soils from Al-Mujama'at Road, one of the Najaf Governorate roads, which is one of Iraq's provinces. The DCP device used in this study was fabricated by the authors using the detailed drawings of the DCP device provided by the (ASTM) American Society for Testing and Materials. The results suggest a correlation between CBR and the DCP with a coefficient of correlation equal to 0. 97, representing a perfect fit for the results in the format of the power equation. [ABSTRACT FROM AUTHOR]

This study aims to predict the subgrade reaction modulus of sand soils by developing a reliable and straightforward statistical model based on dynamic measurements obtained from performing an in-place dynamic cone penetrometer test. To achieve the aim of this research, three testing techniques were carried including (1) dynamic cone penetrometer, DCP, (2) plate load test, PLT (3) sand replacement test, SRM. These tests were implemented under different degrees of compaction using three compactors passes (NOP). Soil parameters obtained from the DCP were CBR, penetration index (DCPI), and bearing capacity (q). The PLT test determined three soil characteristics: subgrade reaction modulus, maximum settlement, young's elastic modulus. The SRM was carried out to assess moisture content, dry density, and degree of compaction. The results of experimental work showed that the highest value of the degree of compaction is (98.85%) for (18 NOP) and the lowest value is (87.43%) in for (10 NOP), the values of ks ranged from 135 to 230 kPa/mm, DCPI value varied from 14.5 to 26 mm/blow, CBR ranged from 8 to 13.5%, q ranged from 105.45 to 149.42 kPa. These results were statistically analyzed and related to finding the best-fit regression model to predict ks. The statistical analysis results exhibited that the ks can be predicted based on DCP measurements and physical properties measurements (degree of compaction (DC), curvature coefficient (Cc), uniformity coefficient (Cu)) with significant R square equals to 88. The statistical analysis finding proved that DCP devices could be used as a non-destructive tool for assessing the subgrade reaction modulus quickly and accurately. [ABSTRACT FROM AUTHOR]

The main purpose of soils compaction ratio computing is to check the compaction ratio of soil fill with respect to maximum soil dry unit weight.This study produces compacting soil ratio calculation based on reading of the soil pocket penetrometer. The pocket value within certain procedure contains testing the same point location selected to test soil layer that adopted in standard normal compaction ratio determination. The four to five points pocket penetrometer tool tested at the compacted topsoil layer surface. The results of (130) points indicated that there is a good agreement between compaction ratio and pocket penetrometer readings with the linear interpolating relationship. The study also predicts linear relationships design equations for predicting compaction ratio and modulus of sub-grade reaction with acceptable regression (R2) values but with certain limitations. [ABSTRACT FROM AUTHOR]

The Zheugzhou airfield is treated by dynamic compaction. The in-situ tests such; is static penetration test. standard penetration test and static load test are used to studied compaction effect for saturated silty soil and silty clay. Finally, the result of test is analyzed to decide the dynamic compaction construction parameters of compaction energy, tamping interval and tamping point arrangement. [ABSTRACT FROM AUTHOR]

This paper is to investigate the mechanism of inclined cone penetration test (CPT) using the numerical discrete element approach. A series of penetration tests with the penetrometer inclined at different angles (i.e., 30°, 45°, 60°, 75° and 90°) were numerically performed. The velocity fields, displacements of soils adjacent to the cone tip, rotation of the principal stresses and the averaged pure rotation rate (APR) are analyzed. Special focus is placed on the penetration mechanism and the effect of inclination angle on the tip resistance. The DEM results show that soils around the cone tip experience complex displacement paths as the penetration proceeds and exhibit characteristic velocity fields corresponding to three different failure mechanisms. The principal stresses near the cone tip undergo apparent rotation, accompanied by large APR which indicates evident particle rotation adjacent to the cone. The normalized tip resistance qN( = qc/σν0) decays with penetration depth in a decreasing rate. At the same penetration depth, qN decreases with the increasing of the inclination angle of penetrometer. [ABSTRACT FROM AUTHOR]

A study on polyvinyl alcohol (PVA) samples had been done to measure the consistency and the apparent diffusion coefficient (ADC) value of PVA. For our experiment, PVA hydrogel samples were formed using freezingthawing method with various concentration and number of freezing-thawing cycles. In our study, PVA consistency was measured by using a penetrometer and the ADC value was obtained from diffusion-weighted magnetic resonance imaging (DW-MRI). The effects of PVA concentration and number of freezing-thawing cycles on consistency value from penetrometer and ADC value from DW-MRI were also observed. [ABSTRACT FROM AUTHOR]

The study about California Bearing Ratio on subgrade is required as the road infrastructure. Some researchers has conducted studies about California Bearing Ratio in both laboratory and the field to figure out the load bearing capacity of the existing soil in the field. The Kunduran – Goa Terawang road is a regency road which connects the Kunduran district and Todanan district. The length of the Kunduran – Goa Terawang is 11,44 km with the endpoint identifier (STA 0 road) from T intersection 3/49 on the provincial road km 25. The Kunduran – Goa Terawang road has experienced damaged from time to time. Therefore, the condition of load bearing capacity on the subgrade must be analysed. The value of load bearing capacity of the subgrade on the road. The California Bearing Ratio had to be conducted to figure out the value. The California Bearing Ratio test was conducted in two ways, 1) the laboratory California Bearing Ratio testing and the field California Bearing Ration using the Dynamic Cone Penetrometer. The testing was conducted in three points, STA 0+250, STA 0+500, dan STA 0+750. [ABSTRACT FROM AUTHOR]

Pectin film samples were prepared from HM, LM and amidated pectins produced by CP Kelco and Danisco, with acidic and enzymatic de-esterification and amidation. The swelling of samples were indicated by hydration before the experiments for 24 h by PEG20000 solution, on known osmotic pressure, with Ca, Mg and K ions with different concentrations. Mechanical tests were followed by Stable Micro Systems penetrometer, with stress-relaxation method, in elastic deformation section. Results show, that the energy absorption depends on the pectin type, on the hydration and the ion concentration. Based on this type experiments it is possible to choose the best pectin type for different uses — as a packaging material in different occasions, or modeling pectin changes during physiological changing in the cell-wall etc. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]