Effect of straw reinforcement on the shearing and creep behaviours of Quaternary loess

AbstractIn addition to the shearing behavior of soil, the creep character is also considered crucial in determining the long-term shear strength. This especially holds true for the loess that possesses the metastable microstructure and is prone to landslide hazards. This study explored the potential application of straw reinforcement to enhance the shearing and creep properties of the Quaternary loess. The mechanism responsible for the straw reinforcement to elevate the peak shear strength was revealed. Furthermore, three creep characters, namely attenuating creep, non-attenuating creep, and viscous flow were identified in this study. The unreinforced and reinforced specimen behaved in a different manner under identical shear stress ratio condition. The reinforced specimen was superior in limiting the particle relative movement within the shear plane than the unreinforced specimen. The chain reaction of interparticle contact loss, accompanied with excessive viscous displacement, rapid weakening of creep resistance, and eventually accelerated creep displacement, provided an evidence for the formation mechanism of slow-moving landslide. The long-term shear strength using the isochronal stress–strain relationship may be used for optimising the design of high-fill embankment works.

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Effects of a layered structure on the physicomechanical properties and extended creep behavior of bamboo-polypropylene composites (BPCs) determined by the stepped isostress method

Holzforschung ◽

10.1515/hf-2017-0165 ◽

2018 ◽

Vol 72 (7) ◽

pp. 589-597 ◽

Cited By ~ 4

Author(s):

Chin-Yin Hsu ◽

Teng-Chun Yang ◽

Tung-Lin Wu ◽

Ke-Chang Hung ◽

Jyh-Horng Wu

Keyword(s):

Creep Behavior ◽

Bottom Layer ◽

Short Term ◽

Creep Properties ◽

Polypropylene Composites ◽

Plastic Composite ◽

Accelerated Creep ◽

Term Creep ◽

Better Than

AbstractA layered bamboo-plastic composite (BPC) consisting of bamboo (Phyllostachys makinoi) particles and polypropylene was investigated. The influence of the layering conditions, including the thickness and bamboo content in various layers, was the focus in terms of the physicomechanical and creep properties of the BPCs. The results showed that a three-layered BPC (BPC3L) with a 1:3:1 thickness ratio and with top/bottom layer containing 40% bamboo exhibited the best specific flexural properties. An accelerated creep test approach was applied, known as the short-term stepped isostress method (SSM), to predict the long-term creep behavior of BPC3L. The results indicated that the creep master curves, which are constructed from different SSM testing parameters, agree well with the long-term experimental creep data and that the creep resistance of homogeneous single-layered BPC was better than that of BPC3L.

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Evaluation of the Creep Strength of 9Cr-1Mo-V and 1Cr-1Mo-1/4V Castings and Weldments Using Accelerated Creep Testing

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4048976 ◽

2020 ◽

Author(s):

Scot Laney

Keyword(s):

Creep Testing ◽

Stress Relaxation Test ◽

Creep Data ◽

Test Program ◽

Creep Properties ◽

Type Iv ◽

Accelerated Creep ◽

Identical Test ◽

Type Iv Cracking

Abstract The traditional method to generate creep data requires several long term tests; in some cases upwards of 100,000 hours. These tests are often time and cost prohibitive to perform. Creep data in literature is limited to commonly available materials in set processing conditions. This speaks very little to the properties for new materials, alternate processing of existing materials, as well as properties for weldments and heat affected zones (HAZ) that occur in the fabrication of large equipment. Due to this, several methods have been developed for accelerated creep testing. One such method, namely, the Stress Relaxation Test (SRT), is discussed as the means to evaluate two different materials and their weldments used in the manufacturing of steam turbine casings. Cast 9Cr-1Mo-V material from two different foundries as well as their weldments and Heat Affected Zones (HAZ) were tested at temperatures between 550oC and 700oC. The SRT generated data closely matches that given in literature. In a nearly identical test program, cast 1Cr1Mo¼V steel showed anomalies in the weld and HAZ behavior. Further investigation showed that the incorrect weld metal was used and a second attempt, poor welding practice lead to failure due to Type IV cracking. These two case studies illustrate the ability of the SRT method to accurately predict creep properties and its sensitivity to detect variations in properties, which can make it useful for rapid verification of casting suppliers and welding procedures for high temperature applications.

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ELEKTRON ZE41A

Alloy Digest ◽

10.31399/asm.ad.mg0070 ◽

1970 ◽

Vol 19 (10) ◽

Keyword(s):

Corrosion Resistance ◽

Shear Strength ◽

Physical Properties ◽

Surface Treatment ◽

Heat Treating ◽

Casting Alloy ◽

Creep Properties ◽

Magnesium Casting ◽

Medium Strength ◽

High Integrity

Abstract ELEKTRON ZE41A is a medium-strength, high-integrity magnesium casting alloy which is fully weldable and has good fatigue and creep properties. It has maximum freedom from microporosity and is applicable up to 320 F. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and shear strength as well as creep and fatigue. It also includes information on corrosion resistance as well as casting, heat treating, machining, joining, and surface treatment. Filing Code: Mg-70. Producer or source: Magnesium Elektron Inc..

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Long-term shear strength weakening of soft interlayers duo to low-permeability

Journal of Contaminant Hydrology ◽

10.1016/j.jconhyd.2021.103840 ◽

2021 ◽

pp. 103840

Author(s):

Chong Ma ◽

Bin Hu ◽

Hongbin Zhan

Keyword(s):

Shear Strength ◽

Low Permeability

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Effect of long-term thermal exposure on microstructure and creep properties of DD5 single crystal superalloy

China Foundry ◽

10.1007/s41230-021-9010-8 ◽

2021 ◽

Vol 18 (3) ◽

pp. 185-191

Author(s):

Xu-dong Wang ◽

Zhong Yang ◽

Qiang Gao ◽

Li-rong Liu

Keyword(s):

Single Crystal ◽

Thermal Exposure ◽

Single Crystal Superalloy ◽

Creep Properties

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Long-term shear strength of geosynthetic clay liners

Geotextiles and Geomembranes ◽

10.1016/j.geotexmem.2007.08.001 ◽

2008 ◽

Vol 26 (2) ◽

pp. 130-144 ◽

Cited By ~ 27

Author(s):

Werner Müller ◽

Ines Jakob ◽

Stefan Seeger ◽

Renate Tatzky-Gerth

Keyword(s):

Shear Strength ◽

Geosynthetic Clay Liners ◽

Clay Liners

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Prediction of Long-Term Creep Properties of Zirconium-2.5 % Niobium Alloy Using Wilshire Method

Materials Performance and Characterization ◽

10.1520/mpc20200146 ◽

2021 ◽

Vol 10 (2) ◽

pp. 20200146

Author(s):

Vivek Patel ◽

R. N. Singh ◽

Madangopal Krishnan

Keyword(s):

Niobium Alloy ◽

Creep Properties ◽

Term Creep

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PLURALISM, THE PEOPLE, AND TIME IN LABOUR PARTY HISTORY, 1931–1964

The Historical Journal ◽

10.1017/s0018246x1300023x ◽

2013 ◽

Vol 56 (3) ◽

pp. 729-756 ◽

Cited By ~ 2

Author(s):

JEREMY NUTTALL

Keyword(s):

Labour Party ◽

Social Progress ◽

Multiple Time ◽

The People ◽

Negative Perceptions ◽

Slow Moving ◽

Progressive Potential ◽

Time Frames ◽

Pluralist Approach

ABSTRACTObserving the increasing, yet still partial exploration of pluralism, complexity and multiplicity in recent Labour party historiography, this article pursues a pluralist approach to Labour on two central, related themes of its middle-century evolution. First, it probes the plurality of Labour's different conceptions of time, specifically how it lived with the ambiguity of simultaneously viewing social progress as both immediate and rapidly achievable, yet also long term and strewn with constraints. This co-existence of multiple time-frames highlights the party's uncertainty and ideological multi-dimensionality, especially in its focus both on relatively rapid economic or structural transformation, and on much more slow-moving cultural, ethical, and educational change. It also complicates neat characterizations of particular phases in the party's history, challenging straightforwardly declinist views of the post-1945–51 period. Secondly, time connects to Labour's view of the people. Whilst historians have debated between positive and negative perceptions of the people, here the plural, split mind of Labour about the progressive potential of the citizenry is stressed, one closely intertwined with its multiple outlook on how long socialism would take. Contrasts are also suggested between the time-frames and expectations under which Labour and the Conservatives operated.

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Shear strength of interfaces in natural and in recycled aggregate concrete

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2016-0317 ◽

2017 ◽

Vol 44 (3) ◽

pp. 212-222

Author(s):

Shakeel Ahmad Waseem ◽

Bhupinder Singh

Keyword(s):

Shear Strength ◽

Shear Plane ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Recycled Aggregates ◽

Failure Envelope ◽

Interface Shear ◽

Aggregate Concrete ◽

Normal Strength ◽

Strength Models

Shear strength of interfaces in natural aggregate concrete and in recycled aggregate concrete has been investigated using initially uncracked push-off specimens by varying the following parameters: replacement level of the recycled aggregates (0%, 50%, and 100%), concrete grade (normal-strength and medium-strength), and clamping force on the shear plane. Development of truss action for resisting interface shear was indicated by the observed crack patterns in the tested specimens and a truss-based analysis recommended in the literature in combination with a simplified failure envelope for concrete subjected to biaxial stresses has been used for shear strength predictions of the tested specimens. The proposed methodology, which is considered to be more rational than the empirical shear strength models available in the literature was calibrated for both the concrete types and gave conservative and reasonably accurate shear strength predictions for selected experiments taken from the literature.

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