Research on Large-Scale Tri-Axial Shear Strength Tests in Slide Zone Soil of Huangtupo Landslide

2016 ◽  
Vol 13 (11) ◽  
pp. 8355-8360
Author(s):  
Wang Yuewei ◽  
Li Yunan ◽  
Hua Shuai
Keyword(s):  
Shear Strength ◽  
Large Scale ◽  
Huangtupo Landslide ◽  
Axial Shear ◽  
Strength Tests ◽  
Slide Zone

Railway Ballast Strength and Permeability Affecting Track Performance Under Dry and Wet Conditions

2018 ◽  
Author(s):  
Issam Qamhia ◽  
Maximilian Orihuela ◽  
Scott Schmidt ◽  
Erol Tutumluer ◽  
Maziar Moaveni ◽  
...  
Keyword(s):  
Shear Strength ◽  
Triaxial Test ◽  
Large Scale ◽  
Field Performance ◽  
Test Machine ◽  
Railway Ballast ◽  
Permeability Characteristics ◽  
Strength Tests ◽  
Dry And Wet Conditions ◽  
And Performance

Railway ballast is a major structural component of railroad track that also facilitates the drainage of water. Particle breakage and abrasion due to dynamic loading and environmental impacts causes ballast to age and degrade. The finer materials generated from ballast degradation can adversely affect the track stability especially under wet conditions. This paper investigates through laboratory testing the effect of moisture on the behavior and performance of in-service ballast. The tested ballast samples were initially subjected to an artificial rain system as well as train loadings in the Facility for Accelerated Service Testing (FAST) at the Transportation Technology Center, Inc. (TTCI). The rainy test section experiment applied realistic dynamic freight train loads and continuously monitored the test sections to determine the effects of moisture and saturation conditions on the field performance trends of ballasted track. Accordingly, ballast samples at varying levels of degradation were collected from the test locations to investigate ballast gradations as well as strength and permeability characteristics at dry and wet conditions. Shear strength tests were performed using a large-scale triaxial test machine, known as the TX-24, to study ballast degradation effects on the strength of dry ballast. Materials finer than the 3/8 in. (9.5 mm) were then collected and studied for the moisture-density behavior using a modified Proctor type compactive effort. Shear strength samples with the same gradations and degradation levels were prepared and tested at varying moisture contents of the 3/8 in. (9.5 mm) fraction ranging from 3% to 9%, with the latter being the optimum moisture content of these finer materials. The wet ballast triaxial test samples had strength values only in the range of 38% to 65% of the dry strengths. In addition to the strength tests, constant head permeability tests were also conducted on the ballast samples which demonstrated quite low and negligible horizontal flow amounts through ballast under static pressure heads and at various hydraulic gradients.

scholarly journals Investigation of Salt-Frost Heaving Rules and Mechanical Properties of Chlorite Saline Soil along the Duku Highway under Freezing-Thawing Action

2022 ◽  
Vol 2022 ◽  
pp. 1-12
Author(s):  
Xuebang Huang ◽  
Zizhao Zhang ◽  
Zezhou Guo ◽  
Ruihua Hao ◽  
Qianli Lv ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Large Scale ◽  
Saline Soil ◽  
Physical Property ◽  
Freezing Process ◽  
Composition Analysis ◽  
Frost Heaving ◽  
Starting Point ◽  
Strength Tests

Aiming to investigate salt-frost heaving rules and the mechanical properties of natural saline soil along the Duku Highway subjected to multiple freezing-thawing cycles, we collected natural saline soil samples from the alluvial-proluvial plain in front of the Dushanzi Mountain at the starting point of the Duku Highway. Then, we conducted mineral composition analysis tests, essential laboratory physical property measurement, large scale multiple freezing-thawing cyclic salt-frost heaving tests, shear strength tests, and unconfined compressive strength tests on the samples. According to the test results presented, the collected saline soil differed from saline soil in other regions and fell into “chlorite saline soils.” As the number of freezing-thawing cycles increased, the overall salt-frost heaving capacity increased and then decreased in the freezing process but first reduced and then increased in the thawing process. Thus, the salt-frost heaving capacity was cumulative in freezing/thawing cycles. The peak salt-frost heaving capacity reached a maximum after 1 freezing-thawing cycle and then dropped drastically and fluctuated regularly. After 6 freezing-thawing cycles, the displacement deformation and time formed a new equilibrium. After 7 freezing-thawing cycles, the displacement and deformation of the soil no longer appear negative. As the number of freezing-thawing cycles increased, the cohesive force of saline soil first increased and then dropped steadily, the internal friction angle first dropped and then increased steadily, and the unconfined shear strength first increased and then decreased. These research results provided data supporting the prevention and controlling highway saline soil disasters with insightful references for the other projects in this region.

Alban Berg

2017 ◽  
Author(s):  
Helen Abbott
Keyword(s):  
Adhesion Strength ◽  
String Quartet ◽  
Large Scale ◽  
Statistical Data ◽  
Alban Berg ◽  
German Translation ◽  
Stefan George ◽  
Strength Tests ◽  
Parallel Texts

When Austrian composer Alban Berg was working on his opera Lulu, he wrote three Baudelaire songs as a Konzertaria entitled Der Wein. Premiered in 1930, Der Wein is a large-scale work for voice and orchestra. Berg uses a German translation by Stefan George, but the published score is in parallel texts, accommodating the French verse line. The chapter also considers a ‘hidden’ Baudelaire setting from Berg’s 1926 Lyric Suite for string quartet. The analysis covers: (a) the context of composition; (b) the connections established between selected poems; (c) the statistical data generated from the adhesion strength tests; and (d) how the data shape an evaluation of Berg’s settings of Baudelaire. Evidence suggests that Berg’s settings of Baudelaire are loosely entangled; the highly prescriptive score affects syntax, semantics, and prosody. Yet, because Der Wein has stood the test of time, the settings are deemed loosely accretive.

scholarly journals Basic Mechanical Parameter Relations of Soft Clay in Pearl River Delta

2014 ◽  
Vol 8 (1) ◽  
pp. 320-325 ◽  
Author(s):  
Zhangming Li ◽  
Na Qi ◽  
Zhibin Masumi ◽  
Weidi Lin
Keyword(s):  
Shear Strength ◽  
Pearl River Delta ◽  
Large Scale ◽  
Soft Clay ◽  
River Delta ◽  
Pearl River ◽  
Cylindrical Cavity Expansion ◽  
In Situ Data ◽  
The Pearl River

Basic parameters relations among CPT parameters, un-drained strength and other mechanical parameters of soft clay are presented based on an elastic-plastic solution for cylindrical cavity expansion for soil investigation in energy engineering. The relation between CPT parameters and shear strength from vane test is also presented based on the result. Thus, the CPT parameters can be determined directly by elastic parameters and shear strength or vane shear parameters and vice versa. That makes it possible to save the high test costs and provide theoretical formulas to avoid some tests which are limited due to the site and/or other condition. Results are compared between the relations and in situ data at a large-scale project in the Pearl River Delta. The results showed consistency between the relation and in situ data.

scholarly journals An Experimental Study on a Composite Bonding Structure for Steel Bridge Deck Pavements

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Xiaoguang Zheng ◽  
Qi Ren ◽  
Huan Xiong ◽  
Xiaoming Song
Keyword(s):  
Tensile Strength ◽  
Shear Strength ◽  
Epoxy Resin ◽  
Bonding Strength ◽  
Bridge Deck ◽  
Steel Bridge ◽  
Shear Tests ◽  
Bonding Structure ◽  
Asphalt Overlay ◽  
Strength Tests

As one of the major contributors to the early failures of steel bridge deck pavements, the bonding between steel and asphalt overlay has long been a troublesome issue. In this paper, a novel composite bonding structure was introduced consisting of epoxy resin micaceous iron oxide (EMIO) primer, solvent-free epoxy resin waterproof layer, and ethylene-vinyl acetate (EVA) hot melt pellets. A series of strength tests were performed to study its mechanical properties, including pull-off strength tests, dumbbell tensile tests, lap shear tests, direct tension tests, and 45°-inclined shear tests. The results suggested that the bonding structure exhibited fair bonding strength, tensile strength, and shear strength. Anisotropic behaviour was also observed at high temperatures. For epoxy resin waterproof layer, the loss of bonding strength, tensile strength, and shear strength at 60°C was 70%, 35%, and 39%, respectively. Subsequent pavement performance-oriented tests included five-point bending tests and accelerated wheel tracking tests. The impacts of bonding on fatigue resistance and rutting propagation were studied. It was found that the proposed bonding structure could provide a durable and well-bonded interface and was thus beneficial to prolong the fatigue lives of asphalt overlay. The choice of bonding materials was found irrelevant to the ultimate rutting depth of pavements. But the bonding combination of epoxy resin waterproof and EVA pellets could delay the early-stage rutting propagation.

scholarly journals Strength Tests and Numerical Simulations of Loess Modified by Desulfurization Ash and Fly Ash

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 512
Author(s):  
Zhi Cheng ◽  
Xinrong Cheng ◽  
Yuchao Xie ◽  
Zhe Ma ◽  
Yuhao Liu
Keyword(s):  
Shear Strength ◽  
Fly Ash ◽  
Power Plants ◽  
Utilization Rate ◽  
Direct Shear ◽  
Test Results ◽  
Mass Ratio ◽  
Direct Shear Tests ◽  
Strength Tests ◽  
Actual Test

Desulfurization ash and fly ash are solid wastes discharged from boilers of power plants. Their utilization rate is low, especially desulfurization ash, most of which is stored. In order to realize their resource utilization, they are used to modify loess in this paper. Nine group compaction tests and 32 group direct shear tests are done in order to explore the influence law of desulfurization ash and fly ash on the strength of the loess. Meanwhile, FLAC3D software is used to numerically simulate the direct shear test, and the simulation results and the test results are compared and analyzed. The results show that, with the increase of desulfurization ash’s amount, the shear strength of the modified loess increases first and then decreases. The loess modified by the fly ash has the same law with that of the desulfurization ash. The best mass ratio of modified loess is 80:20. When the mass ratio is 80:20, the shear strength of loess modified by the desulfurization ash is 12.74% higher than that of the pure loess on average and the shear strength of loess modified by fly ash is 3.59% higher than that of the pure loess on average. The effect of the desulfurization ash on modifying the loess is better than that of the fly ash. When the mass ratio is 80:20, the shear strength of loess modified by the desulfurization ash is 9.15% higher than that of the fly ash on average. Comparing the results of the simulation calculation with the actual test results, the increase rate of the shear stress of the FLAC3D simulation is larger than that of the actual test, and the simulated shear strength is about 8.21% higher than the test shear strength.

A Structural Test Frame with Automatic Loading

1949 ◽  
Vol 53 (466) ◽  
pp. 997-1008
Author(s):  
F. W. Page ◽  
J. C. King
Keyword(s):  
Large Scale ◽  
Material Testing ◽  
Test Equipment ◽  
Structural Components ◽  
Standard Material ◽  
Structural Test ◽  
Strength Tests ◽  
Test Frame ◽  
Automatic Loading

The Design of test frames of all types owes a great deal to the pioneer work of the Structures Department, Royal Aircraft Establishment. This particular frame contains some novel features and has been subjected to some unusual overall calibration tests, particularly in relation to the entirely automatic and centralised control gear.The choice of apparatus for testing large scale structural components may be influenced by many factors. In the present case, the choice of a test frame rather than other types of equipment was governed by the following considerations.In an industrial establishment it is essential that test equipment should be put to maximum use. Unlike a central testing establishment such as the R.A.E., major strength tests are relatively infrequent and therefore the equipment should also be suitable for as much as possible of the development and research testing which cannot be undertaken on standard material testing machines.

scholarly journals Influence of Maximum Particle Diameter on the Mechanical Behavior of Soil-Rock Mixtures

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Zhuoling He ◽  
Junyun Zhang ◽  
Tao Sun
Keyword(s):  
Shear Strength ◽  
Large Scale ◽  
Direct Shear Test ◽  
Shear Test ◽  
Particle Diameter ◽  
Size Difference ◽  
Direct Shear ◽  
Fine Grained ◽  
Fine Grained Soil ◽  
Maximum Particle

With the steady development of the development of the western region in China, the construction of mountain highways has developed rapidly, and the soil-rock mixed filler, as an excellent filler, is widely used in the subgrade filling of mountain highways. Unlike ordinary fine-grained soil, the source of the soil-rock mixtures (S-RMs) is not unique, and the particle size difference is large and the water content is not uniform, resulting in very complicated mechanical properties. But the current highway embankment codes are still mainly established on the fine-grained soil. It is not fully applicable to soil-rock filled embankment. Based on soil-rock filled embankment engineering practice, this research uses a large-scale direct shear test to research the mechanical characteristics of the S-RMs with different maximum particle diameters. According to the large-scale direct shear test of S-RMs with different maximum particle diameters, the shear displacement vs shear stress curve, shear dilation, and strength characteristics with maximum particle diameter were analyzed. Results demonstrate that whether secondary hardening occurs mainly depends on the normal stress and the maximum particle diameter of the filler. At different maximum particle diameters, the horizontal displacement vs vertical displacement curves of the S-RMs can be roughly divided into continuous shearing and beginning of shearing and quick dilation. And the shear strength increases with the increase of the maximum particle diameter. Moreover, the cohesion decreases first and then increases with the increase of the maximum particle diameter, and the internal friction angle increases with the increase of the maximum particle diameter. Therefore, some RBs with large particle diameter added to filler can effectively improve the shear strength of the S-RMs, which may be valuable for realistic engineering.

Shear Strength of Sand–Clay Interfaces Through Large-Scale Direct Shear Tests

2020 ◽  
Vol 45 (5) ◽  
pp. 4343-4357
Author(s):  
Zhong-Liang Zhang ◽  
Zhen-Dong Cui ◽  
Ling-Zi Zhao
Keyword(s):  
Shear Strength ◽  
Large Scale ◽  
Direct Shear ◽  
Shear Tests ◽  
Direct Shear Tests
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