COMBINED METHOD FOR CLEANING PIPES FROM SOIL CORE

The paper is devoted to solving an urgent problem - improving the technology of soil excavation during trenchless pipe laying by vibro-impact pushing with the leading steel casing of the well. A new method for core extraction is proposed, which is based on the effect of its vibration transportation under the influence of combined static-dynamic load. The optimum level of soil moisture is experimentally determined, which contributes to a decrease in lateral friction when it moves along a metal pipe cavity. The results of pilot tests on cleaning a pipe 530 mm in diameter, immersed in soil at full design length of transition using Typhoon-190 pneumatic hammer with a mass of 190 kg are presented. The velocity characteristic of core displacement at changing its moisture content is obtained.

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SUPPOSITIONS OF DEVELOPMENT OF SOIL DRIFTER OF CONTINIOUS ACTION

Interexpo GEO-Siberia ◽

10.33764/2618-981x-2019-2-5-66-74 ◽

2019 ◽

Vol 2 (5) ◽

pp. 66-74

Author(s):

Igor Tichshenko

Keyword(s):

Core Sample ◽

Air Distribution ◽

Soil Core ◽

Combined Method ◽

Elastic Valve ◽

Pipe Line

Features of combined method of hole forming with particular compaction and excavation of soil are considered. Scheme with continuous cycle of drifting and transportation of soil core-sample at pipe line by flow of worked air is proposed. The possibility of using pneumohummer with elastic valve in system of air distribution as drive for soil drifter is studied. Behavior of change of its energetic indicators when there is backpressure at exhaust chamber is clarified.

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BIODIVERSITY OF COLLEMBOLA IN SUGAR MAPLE (ACERACEAE) FORESTS

The Canadian Entomologist ◽

10.4039/ent131613-5 ◽

1999 ◽

Vol 131 (5) ◽

pp. 613-628 ◽

Cited By ~ 6

Author(s):

Fernand Therrien ◽

Madeleine Chagnon ◽

Christian Hébert

Keyword(s):

Sugar Maple ◽

New Records ◽

Light Trapping ◽

Future Research ◽

Sampling Techniques ◽

Soil Core ◽

Light Traps ◽

Regional Patterns ◽

Core Extraction

AbstractCollembola of 12 sugar maple forests of southern Quebec were surveyed through pit-light trapping and soil core extraction. These two sampling techniques were highly complementary, as pit-light traps are more efficient for sampling epigaeic species while soil core extractions are more efficient for hypogaeic species. A total of 108 species representing 38 genera and seven families was collected. Nine genera and 67 species are new records for the province of Quebec and 12 species are new records for Canada. The distribution of species among the different sites is summarized and taxonomic remarks are provided for 20 problematic species. A low percentage of the Quebec collembolan fauna is shared with Ontario and Newfoundland, which probably reflects an incomplete inventory of the fauna rather than highly different regional patterns in collembolan communities. The use of these two complementary sampling techniques is suggested to improve the inventory of Collembola in future research.

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