Field Experimental Investigations of Freezing and Thawing of Highway Subgrade

Application of sandstone in cement-stabilized macadam (CSM) is an effective way to utilize sandstone. To determine the feasibility of using sandstone as a CSM aggregate, a series of experimental investigations, such as unconfined compressive strength (UCS) tests, Brazilian splitting tests and freeze-thaw cycle tests, were conducted on sandstone cement-stabilized macadam (SCSM). Three mixed variables, covering the cement content, aggregate type and curing period, were set as influence factors. The testing results indicated that the UCS, indirect tensile strength (ITS) and frost resistance property of the test-pieces increased with cement content and curing age. Considering the asphalt pavement design specifications for China, the UCS and ITS values of the SCSM complied with the requirements of light traffic road construction before freeze-thaw cycles. However, the SCSM subjected to freezing and thawing meets the requirements only when the cement content is 4.5%. Therefore, it is noteworthy that CSM containing sandstone aggregates should be applied with caution in cold region because of insufficient freeze resistance.

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Glacial and Periglacial Transformation of Palaeokarst in the Lublin-Volhynia Region (Se Poland, NW Ukraine) on the Base of TL Dating

Geochronometria ◽

10.2478/v10003-007-0012-3 ◽

2007 ◽

Vol 27 (-1) ◽

pp. 41-46 ◽

Cited By ~ 4

Author(s):

Radosław Dobrowolski ◽

Stanisław Fedorowicz

Keyword(s):

Genetic Relationship ◽

Experimental Investigations ◽

Considerable Influence ◽

Freezing And Thawing ◽

Tl Dating ◽

Freeze Thaw ◽

Se Poland ◽

Repeated Freezing ◽

Formation Conditions ◽

Close Genetic Relationship

Glacial and Periglacial Transformation of Palaeokarst in the Lublin-Volhynia Region (Se Poland, NW Ukraine) on the Base of TL Dating Distinctly diverse results of TL dating are obtained for the deposits with similar lithofacial features but filling morphologically differentiated karst palaeoforms (dolines, pipes, pockets). The infillings of dolines and pipes are mostly of the Saalian age. Based on sedimentological analysis, their formation conditions are related to sub- or/and terminoglacial environment. The age obtained for all infillings of pockets is underestimated in comparison with lithostratigraphic data. A close genetic relationship between these forms and periglacial conditions seems to indicate that the reduction of TL signal is mostly influenced by the disintegration of grains resulted from the repeated freezing and thawing of glaciogenic deposits. A considerable influence of frost weathering on the decrease of thermoluminescence intensity of mineral grains is indirectly confirmed by the results of experimental investigations consisting in the repeated TL measurements of pockets' infillings after successive freeze-thaw cycles.

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Structural Characteristics of Pultruded FRP Composite Experienced Freezing and Thawing Cyclic Temperature

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.2475 ◽

2010 ◽

Vol 654-656 ◽

pp. 2475-2478

Author(s):

Jae Wook Kim ◽

Kwang Yeoul Shin ◽

Dong Min Ok ◽

Dong Jun An ◽

Soon Jong Yoon

Keyword(s):

Corrosion Resistance ◽

Structural Characteristics ◽

Experimental Studies ◽

Experimental Program ◽

Experimental Investigations ◽

Freezing And Thawing ◽

Construction Sites ◽

Frp Composite ◽

Cyclic Temperature ◽

Strength And Stiffness

Due to the advantages of FRP composite such as corrosion resistance, light weight, high specific strength and stiffness, flexibility, etc., the use of FRP composite in construction sites is increasing steadily. Especially, high corrosion resistance is a very strong point of FRP composite. Although the FRP composite has many advantages, the material properties of FRP composite under various environmental conditions at the construction sites are not well investigated. In this paper, we present the results of experimental investigations of FRP composite experiencing freezing and thawing cyclic temperature. In this investigation, we performed experimental studies to find the stress versus strain characteristics of FRP composite experiencing freezing and thawing cyclic temperature variation. In the experimental program, strength and stiffness of the pultruded FRP composite specimens under uniaxial tension affected by the freezing and thawing temperature change mechanism are evaluated and the results are discussed.

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Experimental investigations on the influence of cyclical freezing and thawing on physical and mechanical properties of saline soil

Environmental Earth Sciences ◽

10.1007/s12665-010-0858-y ◽

2010 ◽

Vol 64 (2) ◽

pp. 431-436 ◽

Cited By ~ 14

Author(s):

Hui Bing ◽

Ping He

Keyword(s):

Mechanical Properties ◽

Saline Soil ◽

Physical And Mechanical Properties ◽

Experimental Investigations ◽

Freezing And Thawing

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Experimental investigations of model pile in freezing and thawing of soil ground

Bulletin of L N Gumilyov Eurasian National University Technical Science and Technology Series ◽

10.32523/2616-68-36-2020-132-3-56-61 ◽

2020 ◽

Vol 132 (3) ◽

pp. 56-61

Author(s):

Zhussupbekov A. ◽

Shin E. ◽

Shakhmov Z. ◽

Tleulenova G.

Keyword(s):

Experimental Investigations ◽

Freezing And Thawing ◽

Model Pile

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Development of FRP-Concrete Composite Bridge Deck in Korea - State-of-the-Art Review -

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.326-328.1705 ◽

2006 ◽

Vol 326-328 ◽

pp. 1705-1708 ◽

Cited By ~ 4

Author(s):

Jeong Hun Nam ◽

Soon Jong Yoon ◽

Hwan Doo Moon ◽

Dong Min Ok ◽

Soon Jung Hong

Keyword(s):

Bridge Deck ◽

Cost Effective ◽

Experimental Investigations ◽

Structural System ◽

Freezing And Thawing ◽

Moisture Effects ◽

Composite Bridge ◽

New Material ◽

Wheel Loading ◽

Composite Bridge Deck

The bridge deck is the most vulnerable element in the bridge system because it is exposed to direct actions of wheel loading, chemical attacks, and temperature and moisture effects including freezing and thawing, shrinkage, humidity, etc. In 1980’s, several countries, such as USA, Japan, and Canada, already realized that the service life of the deck is critical for that of the whole bridge, and the research was initiated to develop new material and structural system to improve deck behavior. In recent years, it has been encouraged to develop more durable, easily constructible, and more cost effective bridge deck than the current one in Korea. In this study, a concise state-ofthe- art survey of the experimental investigations on the FRP-concrete composite bridge deck under developing in Korea is presented.

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Three-Dimensional Structure of Cloned T3 Connector Protein at 1.6nm Resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180161 ◽

1990 ◽

Vol 48 (1) ◽

pp. 282-283

Author(s):

José L. Carrascosa ◽

José M. Valpuesta ◽

Hisao Fujisawa

Keyword(s):

Dna Sequences ◽

Expression Vector ◽

Three Dimensional ◽

Deae Cellulose ◽

Dna Packaging ◽

Dimensional Structure ◽

Two Dimensional ◽

Freezing And Thawing ◽

Three Dimensional Structure ◽

Dimensional Reconstruction

The head to tail connector of bacteriophages plays a fundamental role in the assembly of viral heads and DNA packaging. In spite of the absence of sequence homology, the structure of connectors from different viruses (T4, Ø29, T3, P22, etc) share common morphological features, that are most clearly revealed in their three-dimensional structure. We have studied the three-dimensional reconstruction of the connector protein from phage T3 (gp 8) from tilted view of two dimensional crystals obtained from this protein after cloning and purification.DNA sequences including gene 8 from phage T3 were cloned, into Bam Hl-Eco Rl sites down stream of lambda promotor PL, in the expression vector pNT45 under the control of cI857. E R204 (pNT89) cells were incubated at 42°C for 2h, harvested and resuspended in 20 mM Tris HC1 (pH 7.4), 7mM 2 mercaptoethanol, ImM EDTA. The cells were lysed by freezing and thawing in the presence of lysozyme (lmg/ml) and ligthly sonicated. The low speed supernatant was precipitated by ammonium sulfate (60% saturated) and dissolved in the original buffer to be subjected to gel nitration through Sepharose 6B, followed by phosphocellulose colum (Pll) and DEAE cellulose colum (DE52). Purified gp8 appeared at 0.3M NaCl and formed crystals when its concentration increased above 1.5 mg/ml.

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