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Skrovlighet, hårdhet och ålder : Hur förhåller sig dessa till varandra i kalla förhållanden i MellansverigeMattheos, Nikolaus T. January 2012 (has links)
No description available.
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Relative age dating of the Wahianoa moraines, Mount Ruapehu, New Zealand : thesis submitted in partial fulfilment of the degree of Master of Science in Quaternary Science at Massey University, Palmerston North, New ZealandNolan, Erin Unknown Date (has links)
This study attempts to determine a relative age of the Wahianoa moraines, Mt Ruapehu using three relative age dating techniques: Lichenometry, Schmidt hammer and Boulder roundness. There were three study areas used, termed the Wahianoa ‘A’, ‘B’ and ‘C’ moraines. Upon determining a relative age for these moraines, their timing of their formation was placed within New Zealand’s glacial timescale. This is the first study of its kind conducted on Mt Ruapehu and has left the door open for more research in this field. The species of lichens measured on the Wahianoa moraines were Rhizocarpon subgenus, which the largest diameters were measured using callipers. A total of 606 lichens were measured in the Wahianoa Valley and were processed using the growth curve and size frequency methods. A lichenometric growth curve was constructed from lichens growing in the Ohakune cemetery. The dates derived from both methods placed the formation of the Wahianoa moraines during the Little Ice Age. An L-type Schmidt hammer was used on the boulders in the Wahianoa Valley. A total of 280 measurements were taken off the boulders on the Wahianoa moraines. The results of this method, when compared to Winkler’s (2005) study in the South Island placed the formation of the Wahianoa moraines pre-Little Ice Age. Although no definitive ages could be derived from this comparison due to differences in lithology between the two studies, it provided an idea as to where the formation of these moraines could belong. This is the first time that the Boulder roundness method has been used in New Zealand, having only been developed by Kirkbride (2005). This method was used to determine which of the ridges in the Wahianoa Valley were older. It was found that the Wahianoa ‘A’ moraines were the oldest in the valley followed by Wahianoa ‘B’ and ‘C’ respectively. A climate reconstruction was also conducted for the Wahianoa Valley to see what conditions may have been in existence during the formation of the Wahianoa moraines. The paleo-ELA for the Wahianoa Glacier was estimated using the Accumulation-Area Ratio (AAR), Terminus to Headwall Ratio (THAR), Maximum Elevation of the Lateral Moraines (MELM) and Extrapolation methods. The current ELA was estimated using the AAR, THAR and Extrapolation methods. The difference between these estimates was used to determine what temperature decrease would have caused the formation of the Wahianoa moraines. The average paleo-ELA was found to be c. 1715m, while the current ELA was found to be 2475m which lead to a 4.5°C decrease. This temperature decrease correlates well with that of the Last Glacial Maximum. This study found significant differences in relative age of the Wahianoa moraines. There are a number of factors that can affect the growth of lichens such as micro-environmentalconditions and the fact that a growth curve was constructed off site. Factors such aspetrography can affect the Schmidt hammer results and the Boulder roundness measurements. In addition, precipitation can affect the ELA values which can then cause the wrong placement within a glacial event. Further research lies in the use of the Schmidt hammer on a known age surface such as the Mangatepopo moraines which will aide in a better correlation of relative age. Also, further research using climate reconstructions on Mt Ruapehu and the effect of precipitation will also aide in a better correlation with a glacial event.
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Kamenná moře neovulkanických pňů v severních Čechách: poloha, morfologie, míra zvětrávání. / Blockfields of the neovulcanic pits in Northern Bohemia: location, morphology, weathering rate.Plecháč, Petr January 2019 (has links)
Blockfields as an indicator of landscape development with a specific microclimate is presented in many scientific publications. This diploma thesis is focused on finding the relationship between the hardness of stone blocks and the intake of potential radiation, with an assessment of morphology, location and local conditions. Within the selected study areas in Northern Bohemia was recorded a total of 73 blockfields, of which 22 sites were selected for further investigation. From the results of the statistical analyses was shown the relationship between the income potential of radiation and the degree of ventilation of stone blocks. The analyses also show the relationship between the hardness of stone blocks in the blockfields and the orientation of the blockfields to the world's sides, which proved to be significant. The tests performed by the analyses of each third (high) stone seas have shown the possibility of moving rock blocks downhill.
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Elevation, Longitudinal Profile, And Schmidt Hammer Analysis Of Strath Terraces Through Capitol Reef National Park, Utah: Bedrock Channel Response To Climate Forcing?Eddleman, James L. 13 July 2005 (has links) (PDF)
Elevation, longitudinal profile, and Schmidt hammer data indicate that strath terraces (specifically the lower elevation terraces) mapped in the Fremont River drainage of Capitol Reef National Park are correlative to the terraces of the smaller Pleasant Creek drainage located approximately ten miles to the south. This correlation suggests that drainage development in this area of the Colorado Plateau was strongly dependent upon a regional-scale forcing mechanism (e.g. climate) rather than strictly independent basin-scale processes. Elevations of mapped strath terraces and their associated black volcanic boulder deposits were calculated from geologic maps, Digital Elevation Models (DEM), and Digital Orthophoto Quadrangles of the Fruita and Golden Throne Quadrangles, Wayne and Garfield Counties, Utah. Terraces in both drainages were placed into twenty foot elevation bins and then gathered into larger terrace levels based upon population breaks and the degree of weathering as seen from Schmidt hammer hardness data. Comparison of the two datasets indicate that the two lowest terrace levels of the Fremont River compare well with the two terrace levels of Pleasant Creek both in elevation above the present stream bed and in Schmidt hammer hardness measurements. Our data demonstrate that the Fremont River drainage is likely much older than the smaller Pleasant Creek drainage. Further, correlative terrace data strongly suggests that glacial-interglacial climate forcing played a dominant role in the landscape evolution of both drainages and by inference, the broader Colorado Plateau. Terrace elevation data were compared with recently published cosmogenic ages for several terrace deposits located within the Fremont River drainage. This comparison provides compelling evidence that highest concentrations of preserved terraces may be time correlative with discrete isotopic stages associated with glacial maximum and/or deglacial conditions. Finally, our data also demonstrate that in this area of the Colorado Plateau incision rates are on the order of ~60 to 85 cm/ka, which is on the high end of reported rates from other researchers.
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Kontinentální zalednění severovýchodní části Frýdlantského výběžku / Continental glaciation of the northeastern part of the Frýdlant SpurLehejček, Jiří January 2012 (has links)
North-eastern part of Frýdlantský Spur is situated at the northern foothills of the Jizera Mountains. It represents an area, which was at least twice covered by North-European ice sheet during the Middle Pleistocene. At the same time, it is the region whose hills have the summits around the expected altitudinal limit of the maximum ice sheet extent. Therefore, it is a suitable area to study glacial trimline altitude. Schmidt hammer testing was applied to determine different state of rock surface weathering. Obtained R-values were taken as the most relevant data for glacial trimline determination. Nevertheless, other approaches (GIS analysis, outcrops, block fields and erratics mapping) were also incorporated. Interpretation of these approaches gave the altitudinal limit of ice sheets in the north-eastern part of the Frýdlantský Spur at 500 m a. s. l. ± 20 m.
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Změny vnitřní stavby klastických sedimentárních hornin při zkoušce Schmidtovým kladivem / Modification of rock fabric of clastic sedimentary rocks due to the Schmidt hammer testSnížek, Petr January 2013 (has links)
iv Summary Schmidt hammer is the instrument which is used for the assessment of rock mechanical properties and this instrument is classified as the indirect method. This method is based on the assessment of rebound value (R) of the Schmidt hammer, which is measurred by the amount of rebound of the impact plunger from the surface of tested rock. Schmidt hammer is called as the non-destructive method of rock assessment and it is called as in situ testing method as well. The main objective of this work is provement, that Schmidt hammer testing is destructive method and define degree of damage which is caused in the rock mass. Sedimentary rocks were used for the testing, mostly sandstones and arkose sandstones with different types of cement. This made it possible to test the fraction of the rock mass and the relation between fraction and type of cement. The clasts of the rocks had different properties than it was possible to find the relation between grain size and fraction of the rock. Already in procedure of the testing by Schmidt hammer it was obvious, that this metod is definitely destructive. Rock surface after hitting by plunger of Schmidt hammer gains macroscopically observeable destruction. On the surface is the circular track of the plunger and the surface is grinded. It is possible to wipe the small...
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Determining Material and Geometric Properties of Flat Slab Bridges Without PlansPaudel, Binod 17 August 2016 (has links)
No description available.
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Coastal erosion on Högklint, Gotland: Processes, rate, and future implications / Kusterosion på Högklint, Gotland: Processer, hastighet och framtida konsekvenserGlansholm, Helena January 2015 (has links)
The coastline along Högklint and Gråberget, Gotland, Sweden, was examined in order to establish therate of cliff erosion, erosion patterns, as well as some of the driving factors of the erosional processes in the area. Picture comparisons of the coastline reveal some major geomorphological changes in the area over the last 100 years, and the coast is still changing. At present, gardens are slowly disappearing over the cliff edge, and during storms Buske fishing place is threatened to be destroyed.Cliff retreat values could be obtained on two locations with the help of a Light Detection and Ranging (LiDAR) system. Scans were made with the LiDAR in January and May 2013. The scans were latercompared in CloudCompare and a mean erosion rate of 0.159 m/a was obtained for the Högklint siteand 0.123 m/a for the Gråberget site. The cliffs were also studied with a Schmidt hammer that clearly showed how that the cliff face was more eroded below the visible groundwater table than above it. With Gemini Tinytag data loggers temperatures were measured from October 2012 to May 2013 at the surface of the cliff face and inside the cliff at a depth of 4.5 cm and 9.5 cm. It could be concluded that tempera- tures were within the frost-cracking window (-10 to -3 ºC) for 19.7 Julian days, not consecutive. Due to the visibly high water content in the cliff and temperatures within the frost-cracking window, ice segre- gation within the cliff is a possible eroding factor in the area.The cliffs are subjected to erosion caused by ground-, melt-, and rainwater in a significant degree, possibly even more so than by the impact of breaking waves. It is important that the municipality ofGotland takes action to prevent further damage on personal property and to prevent personal injury. Todo this further studies needs to be done on how future climate change will effect the coast and rate oferosion. / Kuststräckan längs med Högklint och Gråberget, Gotland, Sverige, undersöktes för att etablera erosionshastighet,erosionsmönster och de drivande erosionsprocesserna i området. Genom återfotografering ochbildjämförelse av kuststräckan konstateras stora geomorfologiska förändringar de senaste 100 åren.Kustförändringarna är en pågående process. I dagsläget försvinner trädgårdar bit för bit över klintkantenoch vid varje storm hotas Buske fiskeläge att förstöras.Med en Light Detection and Ranging (LiDAR) radar erhölls data över hur mycket som försvunnitfrån klinten på två platser längs området. LiDAR- skanningarna gjordes i januari och maj 2013. Mätningarnajämfördes sedan i CloudCompare och visade på ett medelvärde av erosionshastigheten på0,159 m/a för platsen vid Högklint och 0,123 m/a för platsen vid Gråberget. Klintarna undersöktes ocksåmed en Schmidt-hammare. Resultatet visar hur klippväggen är mer eroderad under den synliga grundvattennivånän över den. Mellan oktober 2012 och maj 2013 mättes temperaturen på klintväggen, samt4,5 cm och 9,5 cm inne i berget, med hjälp av Gimini Tinytag datainsamlare. Resultatet visar att temperaturenlåg inom spannet för frostsprängning, dvs -10 till -3 ºC, i sammanlagt 19,7 dygn. Dessa lågatemperaturer tillsammans med den höga andelen synligt vatten i klinten möjliggör för bildandet avsegregationsis inne i klinten. Detta kan vara en bidragande orsak till uppluckring av klintväggen ocherosion i området.En betydande del av klinterosionen längs med kusten sker på grund av grund-, smält-, och regnvatten,kanske till och med i högre grad än brytande vågor. Det är viktigt att Gotlands kommun vidtar åtgärderför att förhindra skada på egendom och personskador. Mer studier behövs för att ta reda på hur framtidaklimatförändringar kommer att påverka klintarna och erosionshastigheten längs med kusten.
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Vytvoření předpokladů pro hodnocení vlastností vysokopevnostních betonů s využitím nedestruktivních metod zkoušení / Creating conditions for evaluation of high-strength concrete characteristics using non-destructive testing methodsProcházka, David Unknown Date (has links)
High-strength concrete (HSC) belongs in the recent years to frequently used types of concrete. It allows realization of static challenging structures and also shows due to its dense structure greater durability especially against aggressive media. Currently HSC construction realization abroad is not exceptional. It’s using in the Czech Republic is still limited. When realized, then in a small scale in civil engineering works. The realization of high-strength concrete structures is closely related with the concrete construction quality verification. Good efficiency of the quality control methods can provide non-destructive testing methods (NDT), especially when investigating strength of concrete built in structure. A lack on relevant data for non-destructive testing of HSC in technical and normative rules is to be considered as a significant deficiency. Evident for HSC generally is the lack in literature on deeper analysis of the factors affecting their non-destructive testing, as well a meaningful methodology or practically usable calibration relationships. HSC differs from ordinary concrete not only by used components, but also by more compact structure with different strength – elastic characteristics. Considering these differences, HSC strength prediction can not be performed by using calibration relationships developed for ordinary concrete. Moreover, the question is to what extent the current knowledge of the NDT results influencing factors can be considered as valid. The paper presents findings on the effects of the key factors affecting the measurement results of Schmidt hardness method and ultrasonic pulse method, including recommendations for the practical application of these methods. The problematic of static vs. dynamic modulus of elasticity was also solved. Calibration equations for predicting the compressive strength of HSC from the non-destructive testing parameter were elaborated, showing high cohesion among variables and practically usability.
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