Investigation of the mechanical properties of clay soil at different depths

In this study, with regard to the differences of formation stage and physicochemical properties for different high organic soft clay layers, a series of laboratory tests have been carried out to evaluate the mechanical properties of high organic soft clay in Northeast China. The conventional high-pressure consolidation and strain-controlled triaxial shear tests have been carried out to measure the compression and shear strength of high organic soft clay which formed in different ages. Furthermore, the comparisons of stress-strain relations between undisturbed and remoulded high organic soft clay samples under the confining pressure of 300kPa reveal the significant differences in compression and shear strengths of high organic soft clay at different depths, which can be interpreted by the differences in the degree of decomposition of the soil. The test results show that the degree of decomposition of high organic soft clay greatly depend on its formation stage at different depths, which is deemed to determine the mechanical properties. This study will provide a good guide to civil engineers on the constructions of the foundation.

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Application of the nanoindentation technique for the characterization of varved clay

Open Geosciences ◽

10.1515/geo-2018-0071 ◽

2018 ◽

Vol 10 (1) ◽

pp. 902-910 ◽

Cited By ~ 2

Author(s):

Matylda Tankiewicz

Keyword(s):

Mechanical Properties ◽

Mineral Composition ◽

Layered Structure ◽

Clay Soil ◽

Small Scale ◽

Deconvolution Technique ◽

The City ◽

Varved Clay

AbstractNanoindentation is a test carried out in a small scale, during which a rigid indenter (of known hardness and geometry) is pressed into the tested material. The results of the test are the load and unload curves, from which the harerial characterized by high heterogeneity (like soil – composed of grains and particles of different size and mineral composition), the use of multiple nanoindentation on a predefined grid (Grid Indentation Technique) is reasonable. It allows for the determination of the morphology of the material in a selected scale of observation. In the study, nanoindetation tests were performed on samples of varved clay - soil composed of two alternately arranged layers - occurring near the city of Bełchatów in central Poland. Due to the layered structure of the material, the tests were carried out for both layers separately. The outcomes show that there are significant differences in the values of their mechanical properties. Application of the deconvolution technique also allowed for the estimation of the number of components of both layers and their mechanical properties.

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Pengaruh Penambahan Abu Serbuk Kayu Dan Serbuk Batu Bata Berdasarkan Uji Konsolidasi Dan Waktu Penurunan Tanah Lempung

Media Ilmiah Teknik Sipil ◽

10.33084/mits.v9i2.2170 ◽

2021 ◽

Vol 9 (2) ◽

pp. 124-128

Author(s):

Ranggaski Yoan Vianus ◽

Mohammad Ikhwan Yani ◽

Fatma Sarie

Keyword(s):

Mechanical Properties ◽

Clay Soil ◽

Physical And Mechanical Properties ◽

Central Kalimantan ◽

One Dimensional ◽

Consolidation Test ◽

A Value ◽

Brick Powder ◽

Consolidation Coefficient ◽

Mixed Material

The waste from the wood and brick industry in Central Kalimantan is largely unused. The research objective aims to analyze the physical and mechanical properties of clay soil in the Tumbang Rungan area of Palangka Raya City, Central Kalimantan and the effect of adding sawdust ash and brick powder based on the consolidation test and the time of subsidence of the clay soil using the Terzaghi one-dimensional consolidation method with the addition of a mixture of 2 variations 2,5%, 5% and 7,5%. Tests conducted are to obtain the consolidation reduction value (Sc) and the consolidation coefficient value (Cv). The results of the study using a mixture of sawdust ash and brick powder obtained changes in the Sc and Cv values of the original soil. The original soil has a value of Sc (e) = 0.291 cm and Cv (t50) = 0.01913205 cm²/s, Cv (t90) = 0.031062161 cm²/s and the addition of a mixture of 5% variation of material has decreased the value of Sc (e) = 0.203 cm and Cv (t50) = 0.00722173 cm²/s, Cv (t90) = 0.011679143 cm²/s. The effective mixture variation for adding mixed material to clay is a variation of 5%.

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