scholarly journals Direct Shear and Triaxial Shear test Results on Core from Borehole U-15n and U-15n#10 NNSS in support of SPE.

2018 ◽  
Author(s):  
Scott Broome ◽  
Moo Lee ◽  
Aviva Joy Sussman
2018 ◽  
Vol 26 (1) ◽  
pp. 9-18
Author(s):  
Dooyong Cho ◽  
Jinwoong Choi ◽  
Hoseong Jeong

When Perfobond Rib shear connectors are used as flexural materials in structures such as bridges, they show flexural shear behavior due to external force, rather than direct shear behavior. The aim of this study is thus to analyze the difference between both behaviors. First, we prepared a specimen to analyze direct shear behavior using Perfobond Rib shear connectors, analyzed the characteristics of behavior with a push-out test and proposed a formula of shear resistance assessment. Proposed formula shows a relatively good fit with less than 10% error. A flexural shear test was then conducted based on the result of the direct shear test. Based on the static flexural test it analyzed the flexural behavior and the flexural shear stress it calculated. Direct shear stress and EN 1994-1-1 to lead and be calculated, it compared the flexural shear stress and it analyzed in about the shear resistance stress which it follows in load direction. Finally, we compared both test results, and the comparison showed that the flexural shear stress is approximately 6% stronger than the direct shear stress.


2014 ◽  
Vol 587-589 ◽  
pp. 1305-1310
Author(s):  
Ze Yu Zhang ◽  
Li Yun Peng ◽  
Jian Ye Wang ◽  
Abobakir Abdulali

The basic physical and mechanical properties of Libyan soil are analyzed through some experiments, including direct shear test, grading analysis test and compression test. According to the test results, the soil is named as low liquid limit silt featured by weak strength, high compressibility and permeability, which directly influences sub-grade stability, durability and pavement’s usability. In order to solve these problems, measures are discussed from two aspects, namely, soil improvement and construction method. The strength of the soil is apparently increased by the cement and lime adding, and the compressibility is decreased at the same time. And the rising height of capillary water reducing and protection forms for silt soil slope are also proved to be effective in the subgrade construction.


2006 ◽  
Vol 43 (6) ◽  
pp. 618-625 ◽  
Author(s):  
Giovanni Gullà ◽  
Maria Clorinda Mandaglio ◽  
Nicola Moraci

In situ, seasonal changes expose soils to frequent wetting–drying–freezing–thawing cycles. Such processes can favour and trigger shallow instabilities controlled by the weathering process. This paper presents an experimental study carried out to investigate the effects of the weathering process, caused by the wetting–drying–freezing–thawing cycles, on the compressibility and shear strength of a natural clay. Several specimens were trimmed from block samples of overconsolidated clays taken from a slope in south Calabria, Italy. Specimens were subjected to wetting–drying–freezing–thawing cycles of different durations and then tested with standard equipment (oedometer and direct shear). Test results show that the wetting–drying–freezing–thawing cycles caused a change in the initial microstructure that produced a decrease in the compression index and an increase in the swelling index. Moreover, the direct shear test results show a decrease in the peak shear strength and demonstrate that a larger reduction occurs in the first month of weathering cycles. The intense cycles performed in the laboratory produced a decay of compressibility and a shear strength approaching reconstituted values. The conclusions are important when choosing the shear strength parameters required when studying shallow landsliding in clay slopes.Key words: weathered clay, structure, cycle of degradation, shallow instability.


Author(s):  
Abdul Samad Abdul Rahman ◽  
N. Sidek ◽  
Juhaizad Ahmad ◽  
N. Hamzah ◽  
M. I. F. Rosli

Soil compaction has been a common practice in the construction of highways, embankments, earth dams and other related structures where the condition of the soil is high in void ratio and therefore having a very low in bearing capacity. Therefore, the soil needs to be compacted in order to minimize the void ratio and in the same time would results in having a very high bearing capacity to sustain load. Nevertheless, only a few researches have been done to investigate the method of compaction using different energy on the behavior of shear strength by consolidated drained and direct shear test. In this research, the effect of different compaction in energy of 25 number of blows compared to 40 number of blows on the stress-strain behaviour of drained triaxial test has been done and findings of the data are to be compared with direct shear test. Results reveal that there is an increase in soil unit weight by using different energy in compaction with an increase of 5% from 1790 kg/m3 to 1880 kg/m3 for 25 and 40 number of blows respectively. However, the stress-strain behaviour of the specimens shows differently when compared between consolidated drained triaxial and direct shear test. The shear strength for direct shear-stress is at higher value compared to drained triaxial test. For drained triaxial test, results reveal that the effective friction angles are increase only about 1% from 37° to 38°. This is due to the soil particles rearranging itself with the different applied pressures thus eliminating the effects of different energy on the shear strength of the specimens. However, for direct shear test, the shear strength increases drastically from 29° to 32°. The increase of the shear strength is more likely influence by the soil particle arrangement due to the impact of the energy of the no of blows to the desired specimen.


1990 ◽  
Vol 13 (1) ◽  
pp. 58 ◽  
Author(s):  
PG Knodel ◽  
MR Schoenemann ◽  
MR Pyles

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