The impact of recycled rubber aggregates on material nonlinearity of concrete

Based on the shock damage propagation distances and the median fragility limit of the equipments, the NEI 07–13 employs the shock damage rules for determining the potential for affecting safe shutdown and fuel cooling equipments. However, the NEI 07–13 does not provide more detailed guidance for performing the shock damage assessments, because both the shock damage distances and the methodology for developing the median fragility limit are not provided in NEI 07–13. This paper discussed methodology developed for performing simplified assessments for shock effects considering the material nonlinearity of the impact zone and the soil-structure interaction. Three different models (i.e., linear model, nonlinear mode, and SSI model) were developed to calculate the in-structure shock response. The results of the linear model show the shock response due to aircraft impact would completely propagate from the center of initial impact zone and then along a structure pathway (e.g. wall, floor, basemat) to the in-structure without any energy dissipation. As a result, the in-structure shock response spectra are considerably higher than the spectra associated with the design-basis earthquake in the high frequency range. In order to reduce the shock effects on the in-structure safety-related systems and equipments, the material nonlinearity of the impact zone and the soil-structure interaction were incorporated in the dynamic analysis. The numerical results show that both the material nonlinearity and the soil-structure interaction would obviously absorb the energy of the shock waves, so the in-structure shock response spectra were reduced due to these two factors. Finally, the representative shock response spectra were compared with those used in the seismic margin assessment in order to assess specific equipment survival.

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Experimental Investigation on Evaporation Rate for Enhancing Evaporative Cooling of Pervious Pavement Containing Recycled Rubber

10.4028/www.scientific.net/cta.1.847 ◽

2022 ◽

Author(s):

Khaled Seifeddine ◽

Evelyne Toussaint ◽

Sofiane Amziane

Keyword(s):

Evaporation Rate ◽

Asphalt Pavement ◽

Evaporative Cooling ◽

Urban Heat Islands ◽

Cooling Effect ◽

Heat Islands ◽

Permeable Pavements ◽

Urban Heat ◽

Recycled Rubber ◽

The Impact

Traditional impermeable pavements such as asphalt have dark surfaces and high thermal inertia. During hot weather, they tend to absorb and store solar radiation, which promotes the development of urban heat islands (UHI). Furthermore, permeable pavements are effective in mitigating the urban heat island effect via evaporative cooling. There are many studies in the literature on the hydraulic and mechanical characteristics of permeable pavements, but a few studies focus on the impact of evaporative cooling of these pavements. In this study, 3 types of permeable pavements based on pozzolan, recycled rubber and polyurethane resin were studied during 3 hot days. The objective was to quantify the cooling effect in these innovative permeable pavements compared to a traditional impermeable asphalt pavement. The results of this experiment show that the cooling effect in the new types of draining pavements can last up to two days in the weather conditions of this experiment compared to the traditional asphalt pavement. The evaporation rate and surface temperature of permeable pavements vary in opposite directions. In addition, evaporation in pervious pavements is controlled by the availability of water near the surface. This study is a preliminary step in the design of pavements that contribute to the valorization of rubber waste, to the stormwater management and to the reduction of the effects of urban heat islands during heat waves.

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Environmental Effects of Recycled Rubber in Light-Fill Applications

Rubber Chemistry and Technology ◽

10.5254/1.3547605 ◽

2000 ◽

Vol 73 (3) ◽

pp. 551-564 ◽

Cited By ~ 28

Author(s):

H. S. Liu ◽

J. L. Mead ◽

R. G. Stacer

Keyword(s):

Civil Engineering ◽

Field Tests ◽

Long Term Effects ◽

Engineering Applications ◽

Rubber Material ◽

Drainage Layers ◽

Public Health Officials ◽

Recycled Rubber ◽

The Impact

Abstract Tire shred processors use various mechanical means to reduce the waste stream of tires to components including rubber and steel. There is a stockpile of shredded rubber material in many states that is currently marketed mainly for use as Tire Derived Fuel (TDF). Civil engineering applications such as light landfill cover, and potentially landfill drainage layers are also attractive applications for shredded rubber material. Local environmental protection agencies and state public health officials have been reluctant, however, in some regions to allow recycled rubber to be used in civil engineering applications. An absence of data concerning long-term effects is often cited as justification for these bans. We summarized recent laboratory investigations conducted to quantify possible leachates from various recycled tire compounds. Extension of these results to reported field tests detailing the impact of recycled rubber on air, soil and water quality is also considered, as well as biological and toxicity issues. Finally, we identify areas where additional research is required and suggest approaches supporting “Better Use Determinations” for use of recycled tire rubber in these applications.

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Strength Reduction Factor of Concrete with Recycled Rubber Aggregates from Tires

Journal of Materials in Civil Engineering ◽

10.1061/(asce)mt.1943-5533.0002783 ◽

2019 ◽

Vol 31 (8) ◽

pp. 04019146 ◽

Cited By ~ 9

Author(s):

Amedeo Gregori ◽

Chiara Castoro ◽

Giuseppe Carlo Marano ◽

Rita Greco

Keyword(s):

Reduction Factor ◽

Strength Reduction ◽

Strength Reduction Factor ◽

Recycled Rubber ◽

Rubber Aggregates

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Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

Symposium - International Astronomical Union ◽

10.1017/s0074180900178404 ◽

1962 ◽

Vol 14 ◽

pp. 415-418

Author(s):

K. P. Stanyukovich ◽

V. A. Bronshten

Keyword(s):

Explosive Charge ◽

The Moon ◽

Meteorite Impacts ◽

The Earth ◽

Lunar Craters ◽

The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

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The Geosciences Applied to Lunar Exploration

Symposium - International Astronomical Union ◽

10.1017/s0074180900178222 ◽

1962 ◽

Vol 14 ◽

pp. 169-257 ◽

Cited By ~ 9

Author(s):

J. Green

Keyword(s):

Lunar Surface ◽

Probable Mechanism ◽

Point Of View ◽

Lunar Exploration ◽

Geological Model ◽

Apply Geophysics ◽

Surface Features ◽

The Impact

The term geo-sciences has been used here to include the disciplines geology, geophysics and geochemistry. However, in order to apply geophysics and geochemistry effectively one must begin with a geological model. Therefore, the science of geology should be used as the basis for lunar exploration. From an astronomical point of view, a lunar terrain heavily impacted with meteors appears the more reasonable; although from a geological standpoint, volcanism seems the more probable mechanism. A surface liberally marked with volcanic features has been advocated by such geologists as Bülow, Dana, Suess, von Wolff, Shaler, Spurr, and Kuno. In this paper, both the impact and volcanic hypotheses are considered in the application of the geo-sciences to manned lunar exploration. However, more emphasis is placed on the volcanic, or more correctly the defluidization, hypothesis to account for lunar surface features.

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Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

International Astronomical Union Colloquium ◽

10.1017/s0252921100014718 ◽

1997 ◽

Vol 161 ◽

pp. 197-201 ◽

Cited By ~ 1

Author(s):

Duncan Steel

Keyword(s):

Probability Distributions ◽

Regions Of Interest ◽

Significant Fraction ◽

Organic Chemicals ◽

Impact Speed ◽

The Mean ◽

The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

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Organic Syntheses During the Impact of a Comet with a Gaseous Planet

International Astronomical Union Colloquium ◽

10.1017/s0252921100014706 ◽

1997 ◽

Vol 161 ◽

pp. 189-195

Author(s):

Cesare Guaita ◽

Roberto Crippa ◽

Federico Manzini

Keyword(s):

Polymeric Material ◽

Molecular Form ◽

Parent Compound ◽

Blue Filter ◽

Organic Syntheses ◽

The Impact

AbstractA large amount of CO has been detected above many SL9/Jupiter impacts. This gas was never detected before the collision. So, in our opinion, CO was released from a parent compound during the collision. We identify this compound as POM (polyoxymethylene), a formaldehyde (HCHO) polymer that, when suddenly heated, reformes monomeric HCHO. At temperatures higher than 1200°K HCHO cannot exist in molecular form and the most probable result of its decomposition is the formation of CO. At lower temperatures, HCHO can react with NH3 and/or HCN to form high UV-absorbing polymeric material. In our opinion, this kind of material has also to be taken in to account to explain the complex evolution of some SL9 impacts that we observed in CCD images taken with a blue filter.

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