Study on the Influence of Moisture Content and Drying-Wetting Cycles on the Shear Strength Index of Silt in the West Bank of Qinghai Lake

In this paper, the expressway engineering case along the west bank of Qinghai Lake is taken as the research background, and the typical “aquatic grassland” silt on the west bank of Qinghai Lake is taken as the research object. Through the geotechnical test, wet-dry cycle test, and direct shear test, the influence of moisture content and wet-dry cycle on the shear strength of silt and its indexes are studied. The results show that the shear strength index c and φ of unmodified silt first increase and then decline with the increase of water content, and the optimal moisture content of the shear strength is about 30%. The values of c, φ, and shear strength of remolded silt decrease with the increase of wetting and drying cycles. When the cycles exceed 5 times, the moisture content does not have much effect on the shearing strength.

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Study on the Impact of Cyclic Wetting and Drying on the Shear Strength of Stabilized Expansive Soils

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.96 ◽

2012 ◽

Vol 594-597 ◽

pp. 96-99

Author(s):

Yun Dong ◽

Wei Zhong He ◽

Bao Tian Wang

Keyword(s):

Shear Strength ◽

Shear Test ◽

Expansive Soils ◽

Test Results ◽

Strength Index ◽

Wetting And Drying ◽

Slope Analysis ◽

Normal Strength ◽

The Times ◽

The Impact

To offer or predict the shear strength of stabilized expansive soils after cyclic wetting and drying for the slope analysis, the paper carried out direct shear test on the stabilized expansive soils after different times of cyclic wetting and drying. The test results show: The first 3-5 times of cyclic wetting and drying will cause the shear strength decreased sharply, and after about 7-9 times of cycle, the shear strength will trend to a stable value, which is about 40-60% of the normal strength before the cycles. Logarithm model can well fitted the variation of the shear strength and the times of cyclic, so the shear strength index can be predicted by using the models which was established according to the test results.

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The Correlation of Dynamic Cone Penetration Blow Count of Wind Carried Sand vs. Surface Wave Velocity in West Bank of Qinghai Lake

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.212-213.457 ◽

2012 ◽

Vol 212-213 ◽

pp. 457-460

Author(s):

Jian Kun Liu ◽

Jian Hong Fang ◽

Yong Feng Hou ◽

Jun Hua Xiao

Keyword(s):

Rayleigh Wave ◽

Wave Velocity ◽

West Bank ◽

Qinghai Lake ◽

Wave Method ◽

Cone Penetration ◽

The West ◽

Rayleigh Wave Velocity ◽

Surface Wave Velocity ◽

Dynamic Cone Penetration

Based on a test of wind carried sand roadbed in the west bank of Qinghai Lake, Rayleigh wave method is introduced to measure roadbed compactness of the specific soil in China, and analysis is conducted to find correlation of Rayleigh wave velocity (VR) vs. the blow count (N10) of dynamic cone penetration, then a regression formula is presented.

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Studi Pengaruh Abu Batu Bata terhadap SifatFisik dan Mekanik Lempung Terstabilisasi Kapur dari Kecamatan Tenayan Raya

Civil Engineering Collaboration ◽

10.35134/jcivil.v6i1.18 ◽

2021 ◽

pp. 17-23

Author(s):

Soewignjo Agus Nugroho ◽

Ferry Fatnanta ◽

Giri Prayoga

Keyword(s):

Compressive Strength ◽

Shear Strength ◽

Moisture Content ◽

Compression Strength ◽

Unconfined Compressive Strength ◽

Soft Clay ◽

Setup Time ◽

Unconfined Compression Strength ◽

Unconfined Compression ◽

Optimal Moisture Content

Tenayan Raya Subdistrict is an area that has a thickness of soft clay layer. Some cases of building failure were cracks and tilts due to high shrinkage of soil. Nearby is also a brick home industry center, where ashes are produced from bricks burning. Soil Improvement of Tenayan-Raya's Clay and utilization of brick ash will be carried out in this research. This study aims to stabilize the soil with lime and utilize the brick ash to improve shear strength and bearing capacity of the soil. The study was conducted in the laboratory by making several combinations of content clay, lime, and Brick Ash (BA), for the soil mixture which will be added with 10% ash brick. The effect of curing and soaked will also be seen for its rising on soil properties of Unconfined Compression Strength, and CBR laboratories. The influence of water will also be reviewed on the dry side, optimal moisture content, and wet side. The test results show that the Soil has Low Plasticity soil type category CL-ML symbols, according to the Unified classification. Increasing of strength due to stabilization with lime is obtained in conditions of water in optimal moisture content, where the addition of lime is 10% and 10% brick ash, was produced to increase the maximum value of Unconfined Compression Strength and CBR laboratory value. Curing setup time and saturation (soaked) also had affect the value of Unconfined Compressive Strength and CBR laboratory test. At longer time for curing, shear strength will rise proved by the value of UCS Test andbearing capacity value also increase that can be seen of the laboratory CBR test. Curing will make the shrinkage of clay reduced, this can be proven from differences value of Unconfined Compressive strength test between samples with and without soaked, are relatively small.

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Study on Mechanical Properties of the Expansive Soil Treated with Iron Tailings Sand

Advances in Civil Engineering ◽

10.1155/2021/9944845 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Chengfu Chu ◽

Fei Zhang ◽

Daoxiang Wu ◽

Meihuang Zhan ◽

Yun Liu

Keyword(s):

Shear Strength ◽

Moisture Content ◽

Expansive Soils ◽

Expansive Soil ◽

Friction Angle ◽

Dry Density ◽

Maximum Dry Density ◽

Occlusal Force ◽

Optimal Moisture Content ◽

Tailings Sand

Aiming at researching shear strength parameters of expansive soil modified by industrial waste iron tailings sand, the enhancement of expansive soil is explored from macroscopic and microscopic aspects. After characterization and testing by various means, the results show that expansive soil modified by iron tailings sand will increase the maximum dry density of the improved soil and reduce its optimal moisture content, which is beneficial in tuning the moisture content at the construction site. In addition, iron tailings sand can improve the shear strength of expansive soils. The influence of iron tailings sand on cohesion increases first, then decreases, and reaches the peak value at 30%, while the effect on internal friction angle exhibits a continuously increasing trend. Furthermore, according to mercury intrusion tests and microangle analysis, the addition of iron tailings sand can reduce the tiny pores and enhance the occlusal force of the soil. Simultaneously, it increases the number of large pores, maximizing the macroscopic strengthening of iron tailings sand towards the expansive soil.

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