Classification Of Expansive Soils Research Articles

Classification of expansive soils among problematic soils in the brazilian semiarid from artificial neural networks

The climatological and geomorphological conditions of the Brazilian semiarid region favor the formation of potentially expansive soils. The development of neural networks to identify and classify expansive soils in Pernambuco, and the need to export to soils across the semiarid region of Brazil is investigated in this study using a Multi-Layer Perceptron (backpropagation). The neural network was developed using 87 experimental data points, divided into three groups. The Training Group, consisting of 53 samples, using data inputs: sand percentage, clay percentage, plasticity index, activity index, and geological, pedological, and climatological classification. Selection Group, made up of 17 samples, was used to select the best network architecture, genetics algorithms formed of 7 inputs and 3 hidden nodes. The Test Group used 17 samples to evaluate the predictive accuracy of the expansion potential, obtaining an accuracy rate of 88,2%. This network was validated by applying it to 67 samples of problematic soils of the collapsible, expansive, and soft type from the Brazilian semiarid region, reaching an accuracy of 76,1%. Probabilistic Neural Networks were found to be efficient in evaluating the behavior of expansive soils, with the ability to deal with the absence of sample input data, demonstrating the ability to capture movement trends in the expansion of the soil surface, indicating the functions that introduce the effects of the composition potential on the expansion behavior, and determining the limit values of each of the input variables for the samples from the database used.

Shrinkage properties of natural and diesel oil-contaminated fine soils from central Poland

The objectives of this paper are to provide a regional description of the shrinkage parameters of Neogene clays and glacial tills from central Poland; and to present the effects of hydrocarbon contamination on the shrinkage behaviour of soils. Forty samples containing from 19 to 90% clay-size particles were tested. The comparison of the three methods applied has indicated that the shrinkage limit values obtained by the BS 1377-2 method provide a greater margin of safety when used in the classification of expansive soils and yield the best match in the analysis of the variability of the shrinkage limit in relation to other soil index parameters. A good correlation was found between the shrinkability index and the consistency index, which leads to a new classification of soils. The shrinkage tests of clean and diesel oil-contaminated samples revealed that contamination has a significant and irregular effect on the values of shrinkage parameters. For a low degree of contamination the shrinkage limit of both soils had the lowest values and the volumetric shrinkage was at its maximum, and with increasing diesel oil content the shrinkage limit values tend to increase whereas the volumetric shrinkage decreased.

Methods of Support Vector Machine on Classification of Expansive Soils

The classification of the grade of shrink and expansion for the expansive soils was the initial and essential work for engineering construction in expansive soil area. Based on the principle of support vector machine analysis, a classification model of expansive was established in this paper, including five indexes reflecting the shrink and expansion of expansive soil, liquid limit, swell-shrink total ratio, plasticity index, water contents and free expansive ratio and functions were obtained through training a large set of expansive samples. It was shown that the classification model of SVM analysis is an effective method performed excellently with high prediction accuracy and could be used in practical engineering.

Classification procedures for expansive soils

Most of the national codes of practice do not give characterization and classification of expansive soils, in spite of expansive soils being distributed very widely over almost all geographical locations in the world, causing distress to the structures founded on them and discomfort to the users. A simple user-friendly approach based on the free swell ratio, defined as the ratio of the sediment volume of soil in distilled water to that in carbon tetrachloride or kerosene, is formulated considering the compatibility of the results with oedometer free swell tests and the soil clay mineralogy. Statistical illustrations are provided which clearly indicate that while the assessment of soil expansivity based on index properties is an overestimation, there is a consistency in the classifications based on oedometer test results and the proposed approach. It is recommended that simple approaches such as the one proposed here to classify the expansive nature of soils are entered into standard codes of practice.

Classification of expansive soils by sediment volume method. Technical note : Sridharan, A; Rao, S M; Joshi, S Geotech Test JV13, N4, Dec 1990, P375–380

Classification of expansive soils by sediment volume method. Technical note : Sridharan, A; Rao, S M; Joshi, S Geotech Test JV13, N4, Dec 1990, P375–380

Classification of Expansive Soils by Sediment Volume Method

Abstract A soil expansivity classification is proposed based on the sediment volume ratio defined as the ratio of the sediment volume in 0.025% sodium chloride solution to that in kerosene. The results of the proposed classification agree well with one based on the oedometer test results of compacted soil specimens.

Identification and classification of expansive soils in arid and semi-arid regions

Identification and classification of expansive soils in arid and semi-arid regions

Identification and classification of expansive soils : Oloo, S; Shreiner, H D; Burland, J B Proc 6th International Conference on Expansive Soils, New Delhi, 1–4 December 1987V1, P23–29. Publ Rotterdam: A A Balkema, 1988

Identification and classification of expansive soils : Oloo, S; Shreiner, H D; Burland, J B Proc 6th International Conference on Expansive Soils, New Delhi, 1–4 December 1987V1, P23–29. Publ Rotterdam: A A Balkema, 1988

Identification and classification of expansive soils in China : Huang Xiling Proc 6th International Conference on Expansive Soils, New Delhi, 1–4 December 1987V1, P1–5. Publ Rotterdam: A A Balkema, 1988

Identification and classification of expansive soils in China : Huang Xiling Proc 6th International Conference on Expansive Soils, New Delhi, 1–4 December 1987V1, P1–5. Publ Rotterdam: A A Balkema, 1988