Open Piles Research Articles

Influence of pile shape and pile interaction on the crushable behavior of granular materials around driven piles: DEM analyses

This study presents an analysis and a visualization of the effect that the pile shape has on the penetration resistance of driven piles in crushable granular materials. Discrete Element Method (DEM) simulations of single piles with different shapes (flat tip, open pile, triangular tip) being driven into a previously compacted uniform crushable soil are presented. The results from the DEM simulations showed that the shape of the driven piles has a significant influence on the development of penetration resistance and particle crushing. This study also presents the penetration resistance and particle crushing results when a second flat tip pile was driven in a region near a pre-existing single flat tip pile. It was found that considerable high crushing was induced by the second pile. The second pile induced crushing not only on the particles surrounding itself but also on the particles surrounding the pre-existing pile, showing that particle crushing around a driven pile not only takes place when the pre-existing pile is being driven, but it also occurs during the installation of a second pile, in a region closely located to the first one.

Simple emission-reducing measures in an open biological waste treatment plant

In the course of composting biological waste, concentrations of various thermophilic and thermotolerant microorganisms increase. Moving piles of compost results in increased emissions of Actinomycetes and fungi. The present investigation deals with the reduction of airborne microorganism emission and immission in large-scale composting plants with open piles. Simple measures were introduced in order to reduce the release of bioaerosols when turning piles and the release of dust and bioaerols at large. These measures included the sealing of turning machinery with rubber mats, the wetting of piles before and after turning and regular cleaning and wetting driveways during the dry season. Concentrations of airborne microorganisms during the summer season were determined on 5 days before and after the introduction of emission-reducing measures using the six-stage Andersen cascade sampler. The investigation showed that following the introduction of emission-reducing measures there was, at all locations, a highly significant reduction not only of all culturable indicator organisms (thermophilic actinomycetes and Aspergillus fumigatus) but also of total microorganism concentrations (p < 0,001). The introduction of the simple emission-reducing measures mentioned above, however, reduced the immission in the vicinity of the plant to such a degree that the natural background levels were reached at a distance of 150 m.

Nitrous oxide production by manure samples collected from six manure-handling systems

Stored manures are often considered to be source of nitrous oxide (N2O). A study was done to identify manure characteristics and handling stages related to N2O production. In two laboratory experiments we investigated the production of N2O from several animal manures collected at different stages of manure handling or locations in stored-manure systems. Denitrifying enzyme activity, denitrification and CO2 production rates and chemical and fibre characteristics of manure samples were also determined. Most samples had low rates of N2O production. Exceptions were open piles of fresh beef manure and the moist surface layer near the base of an open pile of poultry manure. Production of N2O was most highly correlated with nitrite plus nitrate (NO2− + NO3−) content of manure regardless of whether results were expressed on a wet or a dry weight basis. Denitrification was the most probable source of N2O because N2O production with acetylene and denitrifying enzyme activities was higher than N2O production without acetylene. Stored manure is potentially an important source of N2O emissions, particularly when storage conditions are conducive to formation of (NO2− + NO3−). Key words: Nitrous oxide production, denitrification, denitrifying enzyme activity, manure

226Ra in waters of an estuarine system formerly affected by direct discharges of wastes from a phosphate fertilizer processing complex

The presence of 226 Ra in an estuary formerly affected by direct discharges of waste from a phosphate fertilizer complex has been investigated. Specific activities ranging from 3.6 to 45.2 mBq/l have been detected. In general, activity levels are lower than those detected when direct discharges were carried out. However, there is still a clear contamination due to the disposal of phosphogypsum in open air piles by the river. Moreover, it seems that 226 Ra is being redissolved from the contaminated bed sediments, which also contributes to an enhancement in the activity levels of the estuary waters.

Methane production of raw and composted solid waste in simulated landfill cells

Methane contributes approximately 20% to the annual increase in global warming, and is explosive at concentrations of 5 to 15% in air. Landfills are the origin of approximately 15% of the total global methane emissions. This study was conducted to determine the potential decrease in methane production from municipal landfills if the organic compo nents of solid waste (SW) are composted prior to landfilling. The quantities and rates of methane production were mea sured using simulated landfill cells containing composted and raw simulated SW. The SW was composted in an open pile and characterized by temperature, pH, ash content and CO2 evolved during aerobic respiration. Assuming a 10% lignin content, the labile carbon fraction was reduced by an esti mated 71% during composting. Over a 6-month period, sim ulated landfill cells filled with raw waste generated 66 liters methane per kg of dry refuse, while cells containing com posted SW produced 31 liters methane per kg of dry compost. Per unit weight of the original dry raw SW, composted SW placed in a simulated landfill environment produced only 15 liters methane per kg dry raw SW which is 23% of the meth ane that was generated when the raw SW was placed directly in the simulated landfill cells.

The seroprevalence of verocytotoxin-producing Escherichia coli in Ontario dairy cows and associations with production and management

The prevalences of neutralizing antibodies to verocytotoxins (VT) from four reference strains of VT-producing Escherichia coli were determined in sera from 306 dairy cows from 164 randomly selected herds in southern Ontario, Canada. Prevalences (and 95% confidence intervals) of antibodies capable of neutralizing VTs from the following reference strains of E. coli were: Strain H30 (VT1), 78.4% (73.7%–83.1%); Strain 32511 (VT2, VT2v), 1.3% (0–2.9%); Strain 933W (VT2), 5.6% (3.0%–8.2%); Strain K12B (VTe), 12.1% (8.5%–15.7%). Thirty-nine sera contained neutralising antibodies to more than one type of VT. Thus, neutralising antibodies to verocytotoxins were common among dairy cows in Ontario, Canada. At the individual-cow level, increased risk of VT1 antibodies was observed in association with an increase in age and in Holstein-Friesian cows compared with other breeds. The herd-level proportion of VT1-positive cows was reduced in association with an increase in herd size, storage of manure in an open pile, and occasional use of equipment to handle both manure and feed.

System for driving open and pipe piles on the ocean floor using pneumatic evacuation and existing hydrostatic pressure

A new pile assembly comprises an open end pipe pile (a cylindrical pipe pile (1) provided with a pile cap (6)) that is provided with: (1) a diaphragm (2) adapted to slide axially within open end pipe pile; (2) a conduit (5) that allows gases and liquids to flow to and from the upper portion of the interior of said open end pipe pile through a conduit port (39); and (3) a one-way valve (comprising chamber (44), sphere (45) and valve exhaust port (46)) that allows gases and liquids to flow from an inlet port (40) (that is below said conduit port) in the interior of said open end pipe pile to said valve exhaust port on the exterior of said open pipe pile. The preferred embodiment of the invention also comprises: (4) an open end pipe pile with a lower end of reduced interior diameter; (5) means for retaining drilling mud in the lower portion of said open end pipe pile; and (6) a flexible riser (8) in the interior of said open end pipe pile that provides a passageway for liquids and gases from said inlet port to said one-way valve. A new process for driving an open end pipe pile into the sea floor at significant depths below the ocean surface is also disclosed. It comprises the steps of: (1) displacing liquid from the interior of an open end pipe pile (that has initially penetrated the sea floor) to the ambient by forcing compressed gas into the upper portion of said open end pipe pile; and (2) evacuating or venting said compressed gas from the upper portion of said open end pipe pile to the atmosphere thereby causing said pile to be driven by existing hydrostatic pressure. In the preferred embodiment of the process, the hydrostatic pile driving is done in a plurality of stages, with each stage comprising said steps (1) and (2). The preferred embodiment of the process also comprises the use of drilling mud: to provide lubrication between the diaphragm and the interior surface of the pipe pile, and between the exterior surface of the soil core and the interior surface of the pipe pile; and to give additional weight to the pile assembly thereby increasing the initial penetration of the sea floor, and preventing piping during the hydrostatic pile driving of step (2).

サイロの閉そく限界寸法に関する実験的研究 Ｉ 粗粒材料の流動特性

There are many storage systems for coarse granular materials, such as coal and limestone, These systems include open piles, silos, domes, and storehouses. The silo system is better than other existing systems from the view point of environmental protection, effective use of a site, centralized control, and maintaining the quality of storage materials. For the silo system, however, the most important problem in design is to decide the hopper geometry parameters of the outlet provided at the bottom part of the silo. Blockage and arching in a silo never take place when the hopper geometry parameters are designed appropriately. For use in the theoretical analysis of the hopper section, there are a number of test methods for grasping the properties of fine granulars, but a test method suitable for coarse granulars, such as coal and limestone have yet to be established. This report shows the results of the flow characteristics by means of static compaction and the uniaxial compression test methods. Therefore, the flow characteristics of coarse granular materials, and those at the time of long-term storage are studied here.

Use of pine bark for preparation of activated carbon and as a soil conditioner

The preparation of activated carbons from ground pine ( Pinus pinaster) bark was studied, using pyrolysis at 600° C in a nitrogen atmosphere for 30 min, followed by activation in a carbon dioxide atmosphere, at temperatures from 800 to 1100°C, for 10 to 40 min. It was shown that the carbons activated at 1000 and 1100°C had excellent adsorption properties. Pine bark pyrolysed in the same way, and in an open pile along with untreated bark, was also compared with peat, on the basis of water-holding capacity and pore size, for its suitability as a soil conditioner.

Emergency Farm Structures for Storing Grain-A Multidisciplinary Evaluation

ABSTRACT PORTABLE, emergency structures (36-m3 and 73-m3 capacities) for the storing of surplus wheat for 6 to 12 mo were developed and tested. Nine emergency struc-tures were compared with an open pile, a steel bin and a plywood bin by measuring moisture content, temperature, C02-02 composition of intergranular air, seed germination, microflora, arthropods, fat acidity, grade, milling and baking quality and mycotoxins. The amount of wheat rejected because of excessive spoilage varied from 0.1 to 4.3 percent in the emergency struc-tures, 0 to 1.2 percent in the steel and plywood bins and 49.5 percent in the open pile. The rusty grain beetle, Cryptolestes ferrugineus was found in large numbers in only the open pile.

FIELD TESTS OF DEVICES TO DETECT INSECTS IN DIFFERENT KINDS OF GRAIN STORAGES

AbstractInsect infestations in farm-stored grain, country elevators, and grain residues or spillages were detected by probes, traps, and scoops. Of 68 storages examined at 50 Saskatchewan farms in 1970, 25 were infested with the rusty grain beetle, Cryptolestes ferrugineus (Stephens). Of 52 storages examined in Saskatchewan in 1971 none of the permanent buildings was infested, but 27%, 30%, and 45% of temporary cribs, open piles, and grain residues, respectively, were infested with rusty grain beetles, fungus beetles, or both. The fungus beetles found most frequently in the traps were Lathridius minutus L. Cryptophagus varus Woodroffe and Coombs, and Cartodere constricta (Gyllenhal). A survey of different grain storages in Manitoba in 1972 showed that 44%, 45%, and 69% of country elevalors, farm granaries, and open piles of grain, respectively, were infested with fungus beetles. None of the storages contained the rusty grain beetle alone but 5% of farm granaries and 31% of open piles examined were infested with both kinds of insects. The least infestation occurred in country elevators and the highest in open piles. In general, the lowest insect infestations were in grain stored in weather-proof buildings, and the highest in exposed grain. Grain in open piles or temporary cribs suffered considerable spoilage. The traps were useful in determining insect distribution and behavior in stored grain.

Conditions necessary for sand digging in laboratory rats

Continuous availability of a sand blocked tube elicited intense and persistent digging by laboratory rats. Neither training nor prior exposure to the apparatus were necessary for response initiation. Continuous presence of an open pile of sand would not elicit digging. No theoretical explanation is offered.