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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
351

Influence of Material Type, Aggregate Size, and Unconfined Compressive Strength on Water Jetting of CIDH Pile Anomalies

Heavin, Joseph Carl 01 March 2010 (has links) (PDF)
Water jetting as a means for removing anomalous materials from cast-in-drilled-hole (CIDH) piles was examined. The primary objective of this research was to establish empirical relationships between different jetting parameters and the removal of commonly occurring anomalous zone materials, including low-strength concrete, slurry mixed concrete, grout, and clay soil. Also investigated was the current standard-of-practice used by water jetting contractors within California. The testing specimens consisted of typical anomalous material with unconfined compressive strengths between 5 and 6,000 psi. The experimental work consisted of water blasting submerged specimens using rotary jets, nozzles, and pumping equipment typically used in construction practice. Two testing protocols were developed. The first testing protocol called for the nozzle to be held stationary and the second allowed the nozzle to be cycled up and down across the anomaly. During testing, material removal rates were measured as a function of jet pressure and standoff distance. Water blasted specimens were cut apart after testing to confirm erosion measurements and to permit inspection of the water blasted surfaces. Based on the results, erosion rates and the effectiveness of water jetting are primarily influenced by unconfined compressive strength, when using standard test equipment and jetting pressures. Further, aggregate size and material type in the anomalous material does not appear to influence both total erosion and erosion rate.
352

Probabilistic time estimation in tunnel projects

Mohammadi, Mohammad January 2021 (has links)
Transport infrastructure projects, including tunneling, suffer from timedelays and cost overrun. A literature review shows that the effect ofuncertainty has been neglected in explaining time and cost overrunmeaning that technical explanations matter. Probabilistic estimations oftime and cost can be employed for dealing with uncertainty in transportinfrastructure projects.In this licentiate thesis, KTH’s probabilistic time and cost estimationmodel for tunneling projects (Isaksson and Stille, 2005, Rock Mech. RockEng., 38, 373-398) was improved. The improvements include breakingdown the production activities into their sub-activities, which form thebasis for assessing times (or costs) for tunnel construction. In addition, theexceptional time and the length of model’s geotechnical zones aredescribed as stochastic variables instead of deterministic values used in theoriginal model. Given its hierarchical structure, the model can be used fortime and cost estimation of all types of tunnels and all constructionmethods in various geological condition.The improved version of the model uses three types of input parametersthat are probabilities of occurrences of different geological condition andidentified undesirable events, production effort of sub-activities (i.e. timespent for performing the sub-activity per unit length of tunnel) andadditive delay time that is imposed as a result of occurrence of undesirableevents. The important issues in modeling the uncertainty in the productionefforts of sub-activities are also explained. / Transportinfrastrukturprojekt, inklusive tunnelbyggnad, lider ofta avförseningar och ökade kostnader. En litteraturgenomgång visar atteffekten av osäkerhet inte har beaktats när man försöker förklara orsakentill förseningar och kostnadsökningar, vilket betyder att osäkerheten omgeotekniska förhållanden mycket väl kan spela en stor roll. För att hanteradenna osäkerhet när man bedömer tid och kostnad för tunnelprojekt kansannolikhetsbaserade metoder användas.I denna licentiatuppsats förbättrades den sannolikhetsbaserade modellför tid och kostnadsskattning i tunnelprojekt som tidigare utvecklats påKTH (Isaksson och Stille, 2005, Rock Mech. Rock Eng., 38, 373-398). Denviktigaste förbättringen var att dela upp produktionsaktiviteterna idelaktiviteter, för vilka man sedan enklare kan bedöma tidsåtgång (ellerkostnader). Dessutom beskrivs exceptionella förseningar och längden påmodellens geotekniska zoner nu med stokastiska variabler istället för meddeterministiska värden. Modellen är flexibel nog att kunna användas förtids- och kostnadsskattning av alla typer av tunnelprojekt ochkonstruktionsmetoder i olika geologiska miljöer.Den förbättrade versionen av modellen använder tre typer avindataparametrar: sannolikheter för förekomster av olika geologiskatillstånd och identifierade oönskade händelser; produktionsinsats fördelaktiviteter (d.v.s. den tid som används för att utföra delaktiviteten permeter tunnel); samt försening som orsakas av oönskade händelser.Uppsatsen diskuterar även de viktigaste aspekterna vid modellering avosäkerheten i produktionsinsatsen för delaktiviteter. / <p>QC 20211102</p>
353

Ground vibrations due to pile and sheet pile driving : influencing factors, predictions and measurements

Deckner, Fanny January 2013 (has links)
Ground vibrations due to pile driving are part of a complex process. Vibration is generated from the pile driver to the pile. As the pile interacts with the surrounding soil, vibrations are transferred at the pile-soil interface. The vibration propagates through the ground and interacts with structures, both above ground and underground. The vibration continues into the structure where it may disturb occupants and/or damage the structure. In this thesis the study of the vibration transfer process due to pile driving is limited to the vibration source and the wave propagation in the soil. Vibration transmission to adjacent buildings and structures is not studied. However, impact of vibrations on buildings is briefly discussed in the literature study. It is important to accurately predict the magnitude of ground vibrations that result from pile driving in urban areas, both over- and underestimated vibration levels lead to increased costs. A lot of research has been performed within this field of knowledge, but a reliable and acknowledged prediction model for vibrations induced by pile or sheet pile driving is still needed. The objective of the research project is to increase the knowledge and understanding in the field of ground vibrations due to impact and vibratory driving of piles and sheet piles. This research project also aims to develop a reliable prediction model that can be used by practising engineers to estimate vibration due to pile driving. This licentiate thesis presents the first part of the research project and aims to increase the knowledge and understanding of the subject and to form a basis for continued research work. The most important findings and conclusions from this study are: The main factors influencing vibrations due to pile and sheet pile driving are; (1) the vibrations transferred from the pile to the soil, (2) the geotechnical conditions at the site and (3) the distance from the source. The vibrations transmitted from the pile to the soil depend on the vibrations transferred to the pile from the hammer, the pile-soil interaction and the wave propagation and attenuation in the plastic/elasto-plastic zone closest to the pile. There is today no prediction model that fulfils the criteria of the “perfect” prediction model; reliable but yet easy to apply. Future research should study the transfer of vibrations at the pile-soil interface, including the generation of a plastic/elasto-plastic zone in the area closest to the pile and how that affects the transfer of vibrations from the pile to the soil. / Markvibrationer på grund av pålning är del av en komplex process. Vibrationer genereras från pålmaskinen till pålen. När pålen kommer i kontakt med den omgivande jorden överförs vibrationer mellan påle och jord. Vibrationerna fortplantar sig som vågor genom marken och träffar byggnader och andra konstruktioner, både ovan och under jord. Vibrationerna fortsätter in i byggnaden där de kan orsaka störningar eller skador. I denna avhandling begränsas studien av vibrationsöverföringsprocessen till vibrationskällan och vågutbredningen i jord. Vibrationsöverföringen till intilliggande byggnader eller konstruktioner har inte studerats. Påverkan av vibrationer på byggnader diskuteras dock kort i litteraturstudien. Det är viktigt att på ett tillförlitligt sätt kunna förutsäga markvibrationerna på grund av pålning i stadsmiljö, både över- och underskattade vibrationsnivåer leder till ökade kostnader. Forskning har tidigare utförts inom detta område, men en tillförlitlig och allmänt accepterad prognosmodell för vibrationer på grund av pålning eller spontning saknas fortfarande. Syftet med forskningsprojektet är att öka kunskapen och förståelsen för markvibrationer som uppkommer vid installation genom slagning eller vibrering av pålar och spont. Forskningsprojektet syftar också till att utveckla en tillförlitlig prognosmodell som kan användas av yrkesverksamma ingenjörer för att uppskatta vibrationsnivåer orsakade av pålning. Denna licentiatavhandling presenterar den första delen av forskningsprojektet och syftar till att öka kunskapen och förståelsen inom ämnesområdet samt att skapa en plattform för det fortsatta forskningsarbetet. De viktigaste resultaten och slutsatserna från denna studie är: De huvudsakliga faktorer som påverkar vibrationer orsakade av pålning är; (1) de vibrationer som överförs från källan till jorden, (2) de geotekniska förhållandena på platsen och (3) avståndet från vibrationskällan (pålen). Vibrationerna som överförs från pålen till jorden beror på de vibrationer som överförs från pålmaskinen till pålen, påle-jord interaktionen samt vågutbredning och dämpning i den plastiska/elasto-plastiska zonen som bildas närmast pålen. Det finns idag ingen prognosmodell som uppfyller kriterierna för den ”perfekta” prognosmodellen; tillförlitlig men ändå lätt att tillämpa. Framtida forskning bör undersöka överföringen av vibrationer mellan påle och jord, innefattande uppkomsten av en plastisk/elasto-plastisk zon närmast pålen och hur det påverkar vibrationsöverföringen från påle till jord. / <p>QC 20130314</p>
354

Excess pore water pressure generation in fine granular materials under cyclic loading -A laboratory study

Do, Tan Manh January 2021 (has links)
Abstract Excess pore water pressure can be generated in subgrades of both railway and pavement sub-structures under cyclic loading caused by heavy traffic. When saturated subgrades are subjected to cyclic loading, excess pore water pressures accumulate over time which then could lead to migration of particles into overlying layers. The migration of subgrade soil particles to the upper layers would lead to clogging of pores and reducing the upper layers' drainage capacity. Both excess pore water pressure accumulation and migration of fine particles could negatively affect the long-term performance and service life of the sub-structures and eventually may lead to failure. Understanding the mechanism of both excess pore water pressure and migration of fine particles under cyclic loading is, therefore, essential for not only designing but also further proposing efficient and economical maintenance methods. The main objectives of this research are to (1) investigate excess pore water pressure generation in fine granular materials under cyclic loading and (2) evaluate migration of fine granular materials into overlying layers under cyclic loading.  A series of undrained cyclic triaxial tests were performed to study the excess pore water pressure generation in fine granular materials. Two types of fine granular materials, i.e., railway sand (natural granular material) and tailings (artificial granular material), were selected for this investigation. The cyclic characteristics of these materials, e.g., accumulated strain and excess pore water pressure, were evaluated in terms of number of cycles and applied cyclic stress ratios (CSR). As a result, axial strain and excess pore water pressure accumulated over time due to cyclic loading. However, its accumulations were significantly dependent on CSR values and material types. Finally, a relationship between excess pore water pressure and accumulated strain of the fine granular materials was discovered based on all outputs from the undrained cyclic triaxial tests (both tailings and railway sand samples).  In order to evaluate the migration of fine granular materials into overlying layers under cyclic loading, a modified large-scale triaxial system was used as a physical model test. Samples prepared for the modified large-scale triaxial system composed of a 60 mm thick gravel layer overlying a 120 mm thick subgrade layer (tailings and railway sand). The quantitative analysis on migration of the fine granular materials was based on the mass percentage and grain size of migrated materials collected at the gravel layer. In addition, the cyclic responses (strain and pore water pressure) were evaluated. As a result, the total migration rate of the railway sand sample was found to be small. There were no migrated sand particles pumped up to the gravel surface, i.e., no mud pumping, after the test terminated. The migrated sand particles were observed and collected at the bottom half of the gravel layer. The total migration rate of the tailing sample was much higher than that of the railway sand sample. In addition, the migration analysis revealed that finer tailings particles tended to be migrated into the upper gravel layer easier than coarser ones under cyclic loading. The migrated tailings particles were observed at the surface of the gravel layer after the test ended. It could be involved in significant increases in excess pore water pressure at the last cycles of the physical model test. The findings obtained in this research may provide an additional contribution to the literature dealing with the excess pore water pressure accumulation and its effects on the migration of fine particles under cyclic loading.
355

Sedimentation and Consolidation of cohesive and non-cohesive soils formed under turbulent flows

Almabruk, Adam January 2018 (has links)
Settling and consolidation of suspended clay particles are significant issue in many fields such as geotechnical engineering, coastal and hydraulic engineering, and environmental engineering. A comprehensive literature review was conducted on the settling, consolidation and erosion of mixed soil material (cohesive and non-cohesive). Soil beds formed by sedimentation process of loose particles will be either show a segregated or homogeneous in structure, depending on the depositional environment. These sediments initially undergo self-weight consolidation and may be eroded under high flow rate. A number of studies have recently investigated the characteristic of consolidated clay bed in stagnant water. Hence, consolidation parameters were determined using a well-known vertical settling column consolidation test setup. However, limited research studies are available for deposition and consolidation of a mixture of sediment (clay, silt and sand) under flow conditions which are more representative of what happens in nature. A long flume and pump were used to create different turbulent conditions and simulate the natural process... The results for deposition and consolidation of different mixtures under stagnant and turbulence conditions were analyzed and compered in term of compressibility, permeability as well as shear strength. The results of this experimental research program indicated that the flow rate, initial concentration, height of settling and composition of sediment are all important factors that could affect the final bed dry unit weight. Two non-intrusive techniques were applied for measuring the dry unit weight at settling and consolidation stages. Impact echo technique has never been applied to measure the dry unit weight of self-weight consolidation along the vertical stratification of cohesive and non-cohesive particles. Also, a novel conductance sensor has been developed to improve the efficiency of this technique. The limitations of using these techniques will be highlighted in this study.
356

Loads Analysis of Fixed-Bottom and Floating Offshore Wind Structures

Davis, Michael G 01 September 2023 (has links) (PDF)
Offshore wind in the United States is a rapidly growing industry. The development of both fixed bottom and floating platforms is important for the success of the industry. While monopiles are common substructures in Europe, the Atlantic Coast has a much greater risk for hurricanes. It is necessary to understand how extreme weather events will impact the structures. Meanwhile, floating offshore wind will be key for offshore wind development along the Pacific Coast, Hawaii, and Gulf of Maine. Before these projects can come to fruition, the cost of development must first decrease. A taut mooring system with multiline anchors may be able to reduce costs, specifically when deployed in deep water locations. This thesis considers these concerns for both the fixed bottom and floating wind developments. A parametric study is completed using OpenFAST for a variety of mooring systems. A taut multiline mooring system is designed for water depths ranging from 850 to 2000 meters. Further 850-meter designs explore how changing line properties impact the mooring line and multiline loading. Using these mooring designs, preliminary suction anchors are designed, focusing on the potential savings of decreasing the number of anchor installations from 3 single line anchors per turbine to 1 multiline anchor per turbine. Anchors are designed for a range of soil conditions to observe their impacts on anchor dimensions. For monopile design, four Atlantic Coast wind developments are chosen for design of monopiles at each site, using 50-year and 500-year storm conditions in the design process. These monopiles are designed using primarily hand calculations, with the assistance of OpenFAST to create a hub thrust power curve. The loads are then used to design monopile for a constant diameter and thickness from the transition piece to the mudline. The constant diameter monopiles are compared to a design that was complete for fatigue loading. In general, the fatigue loaded monopiles were required to be much larger, providing capacities larger than the monopiles designed for extreme storm conditions.
357

Spatial variation in uplift pressure and correlation with rock mass conditions under two buttress dams : A case study of Ramsele and Storfinnforsen dams

Alcalá Perales, Diego January 2016 (has links)
Uplift water pressure is one of the dominating forces with signicant impact acting on a dam. It is usually measured with piezometers installed along the dam. However, the value of the pressure along the dam is often hard to measure due to the limited number of piezometers available (Bernstone et al., 2009). Furthermore, uplift pressure can oscillate substantially in a single hole both with time and also spatially under the dam due to the combination of rock mass characteristics in the foundation, loads and temperature variations.There is still a lack of information regarding the magnitude and variation of the uplift pressure. The aim of this thesis is to investigate the spatial variation of the uplift pressure based on uplift pressure measurements taken from Storfinnforsen and Ramsele dams. The aim is also to investigate how the uplift pressure depends on the rock mass conditions. The two dams Storfinnforsen and Ramsele provides a unique opportunity due to the signicant amount of piezometers, 270 in total, installed along the rock foundation for the new monitoring programme at the monoliths of both dams.Based on the measured uplift pressure, a probabilistic distribution has been assigned to the uplift pressure. In addition, a possible correlation between the rock mass quality and the uplift pressure as well as the joint aperture and the uplift pressure was analysed.
358

Partialkoefficientmetodens applicerbarhet på dimensionering av sprutbetong mot enskilda block : Fallstudie: Citybanan i Stockholm

Björkman, Rasmus, Jabbar, Atheer January 2016 (has links)
Målet med det här examensarbetet var att undersöka hur väl dagens partialkoefficienter för sprutbetong tar hänsyn till samhällets normer och säkerhetskrav vid dimensionering enligt partialkoefficientmetoden. Det brottfall som har undersökts för dimensionering av sprutbetong är vidhäftningsbrott vid god vidhäftning. Vidhäftningsbrottet har undersökts med hjälp av en sannolikhetsbaserad metod benämnd ”First-Order Reliability Method”, FORM. Metoden förutsätter kännedom om sannolikhetsfördelningar för ingående variabler i brottgränstillståndet som i det här arbetet till stor del baserats på provtagningar från projektet Norrströmstunneln i Citybanan. Resultatet av undersökningen visar att partialkoefficienterna antar otillåtna värden för dimensionering av sprutbetong på grund av den stora spridningen som råder i framförallt vidhäftningsparametern. Vidhäftningsparametern antog en normalfördelning med medelvärde 0.808 MPa och standardavvikelse 0.319 MPa vid analys av samtliga vidhäftningsmätningar. Spridningen för vidhäftningsparametern har reducerats genom att undersöka gnejs och granit var för sig och genom att ta bort mätningar där dålig vidhäftning i förväg kunnat antas. För granit fick vidhäftningsparametern ett medelvärde på 0.759 MPa och en standardavvikelse på 0.264 MPa. För gnejs fick vidhäftningsparametern ett medelvärde på 0.820 MPa och en standardavvikelse på 0.279 MPa. I den här fallstudien resultera en reducerad spridning för vidhäftningsdata inte i någon avgörande skillnad för beräknade partialkoefficienter. Modellen för vidhäftningsbrottet verkar tillsynes inte vara för komplicerad men det existerar samtidigt stora osäkerheter i modellen och ingående variabler gällande laster och bärförmågor. Framförallt okunskapen gällande lastvariabeln gör det svårt att kalibrera relevanta partialkoefficienter med FORM.
359

Evaluation of cone factors for CPT-evaluation in CONRAD of sulphide- bearing soil in Mälardalen / Utvärdering av konfaktorer för CPT-utvärdering i CONRAD för sulfidjord i Mälardalen

Garpefjäll, Matilda, Hildingsson, Hugo January 2020 (has links)
The purpose of this master thesis is to investigate how to evaluate CPT-soundings in sulphide soilfrom Mälardalen in CONRAD. The objective is to conclude whether sulphide soil from Mälardalenshould be evaluated with existing methods or a new method should be developed. The only existingevaluation methods for sulphide soil are empirically derived for sulphide soil along the coast of Gulfof Bothnia known as Svartmocka. There are currently no guidelines for when to use this evaluationmethod. In the industry, sulphide soil in Mälardalen is evaluated as clay for lack of alternatives, butthis solution has no scientific basis. There is therefore a need for an extended investigation on howsulphide soil from Mälardalen should be evaluated. Previous research has been summarized and provides the basis for the design of the analysis method. Geotechnical investigation data from two sites have been collected and analysed: Spångadalen, innorthwest Stockholm and part of the new railway Norrbotniabanan located north of Umeå in thenorthern part of Sweden. At Spångadalen, the main reason for the investigation is the construction oftwo storm water management ponds. Here some extended laboratory experiments have been carriedout to supplement existing data.Since the purpose of this thesis is to investigate how to evaluate the sulphide soil in Mälardalen, thedata from Spångadalen has be evaluated both with the method for clay and sulphide soil. The datafrom Norrbotniabanan has only been evaluated as sulphide soil. The comparison between theevaluation methods and areas is bases on the difference between the different investigation methods. The parameters of undrained shear strength, pre-consolidation pressure and overconsolidation ratiofrom CPT-soundings has been compared with the same parameters from direct shear tests, fall conetests, field vane tests and CRS. The comparison has also included the spread of the evaluated CPTs indifferent areas. Further the cone factors for the undrained shear strength and pre-consolidationpressure in the empirical equations in CONRAD has been evaluated for the soil in Spångadalen. Theevaluated in based on the evaluation of the CPT preformed in CONRAD and values for the undrainedshear strength and pre-consolidation pressure from other reference methods. The cone factors for theundrained shear strength and pre-consolidation pressure were then compared to the existing conefactors.The conclusion is that no significant results indicates that sulphide soil in Mälardalen differs fromclay although it shares some characteristic with the sulphide soil from Norrbotniabanan. Sulphidesoil from Spångadalen should not even be called sulphide soil since the amount of sulphide was toolow, which was discovered during the study. It should instead be called clay with elements of sulphide. Sulphide soil from Mälardalen should therefore continue to be evaluated as clay. However, furtherresearch on the subject is needed to ensure this conclusion for other areas with sulphide soil in Mälardalen. / Syftet med denna examensuppsats är att undersöka hur CPT-undersökningar I sulfidjord från Mälardalen bör utvärderas i CONRAD. Målet är att genom analys finna underlag för slutsatser,antingen för att sulfidjord från Mälardalen bör utvärderas med befintliga metoder eller att en nyutvärderingsmetod bör utvecklas. De befintliga utvärderingsmetoderna för sulfidjord är empiristbaserade på sulfidjord längst med kust av Bottenviken, känd som Svartmocka. Idag saknas detriktlinjer för när denna ut metod ska användas och i branschen utvärderas sulfidjord från Mälardalensom lera i brist på alternativ. Denna lösning saknar dock vetenskaplig grund. Det finns därför ettbehov av en utökad undersökning kring hur sulfidjord från Mälardalen bör utvärderas.Tidigare forskning har sammanställts och lagat till grund för utformningen av analysmetoden.Geotekniska undersökningsdata från två områden har samlats in och analyserats. Ett område ligger iSpångadalen väster om Stockholm i Mälardalen. Det huvudsakliga skälet till undersökningarna ärbyggandet av två dagvattendammar. Det andra området ligger norr om Umeå i norra delen av Sverige.De undersökningarna kommer från en del av den nya järnvägen Norrbotniabanan. I Spångadalen harutökade laboratorieförsök utförts som komplement till befintliga data.Då syfte med denna uppsats är att undersöka hur sulfidjord i Mälardalen bör utvärderas harundersökningarna från Spångadalen utvärderats med metoderna för både lera och sulfidjord.Undersökningarna från Norrbotniabanan har endast utvärderats som sulfidjord. Jämförelsernamellan de olika utvärderingsmetoderna och utvärderingsmetoderna baseras på skillnaderna mellande olika undersökningsmetoderna. Parametrarna för odränerad skjuvhållfasthet,förkonsolideringstryck och överkonsolideringsgrad från CPT-sonderingarna har jämförts medsamma parametrar från direkt skjuvförsök, fallkonförsök, vingförsök och CRS. Jämförelseninkluderar också spridningen av de utvärderade CPT-sonderingarna i olika områden.Fortsättningsvis har konfaktorerna för den odränerade skjuvhållfastheten ochförkonsolideringentrycket i de empiriska ekvationerna för CONRAD utvärderats för jorden iSpångadalen. Utvärderingen baserades på CPT resultaten från CONRAD och värden för denodränerade skjuvhållfastheten och förkonsolideringstrycket från andra referensmetoder.Konfaktorerna för den odränerade skjuvhållfastheten och förkonsolideringstrycket jämfördes sedanmed de befintliga konfaktorerna.Slutsatsen är att inga signifikanta resultat visar på att sulfidjord från Mälardalen avviker från leratrots att den i vissa avseenden liknar sulfidjord från Norrbotniabanan. Sulfidjord från Spångadalenbör inte ens benämnas som sulfidjord då sulfidhalten var för låg, vilket upptäcktes under projektet.Den bör istället benämnas som lera med inslag av sulfid. Sulfidjord från Mälardalen bör därför ävenfortsatt utvärderas som lera. Dock behövs fortsatt forskning inom ämnet behövs för att säkerställadenna slutsats.
360

CPTu Configuration Impact on Evaluated Undrained Shear Strength / Påverkan av CPTu-konfiguration på utvärderad odränerad skjuvhållfasthet

Mjöberg, Mårten, Stenfors, Axel January 2020 (has links)
This thesis evaluates the commonly used geotechnical probing method CPTu, on how different probe configurations impact the resulting evaluated undrained shear strength in soft clay deposits, in comparison to each other and laboratory methods. This is done by performing field investigations on Lindefältet, Södermanlands län, Sweden. Comparison is done on the two Swedish manufacturers of CPTu probes, by different calibration limits, filter types and whether overloading the probe over the calibration limit affects the evaluated undrained shear strength registered. The main conclusions are that one of the manufacturers’ probes registers deviating results in one configuration, that calibration limit has a noticable impact on the results, and that overloading on the probe and filter choice has negliable impact on the results. / I detta examensarbete utvärderas den vanligt förekommande geotekniska sonderingsmetoden CPTu, på hur olika konfigurationer av sonder påverkar den resulterande utvärderade odränerade skjuvhållfastheten i lösa leravlagringar, 9i jämförelse med varandra och med laboratoriemetoder. Detta är genomfört genom fältundersökningar på Lindefältet, Södermanlands län. Jämförelsen gjordes på de två svenska CPTu-tillverkarnas sonder. Detta är gjort med hänsyn till olika kalibreringar av konspetstryck, filtertyper, och huruvida sonden har varit överlastad påverkar den utvärderade skjuvhållfastheten som registreras. De huvudsakliga slutsatserna är att en av tillverkarnas sonder registerar udda värden i en konfiguration, att kalibreringar av konspetstryck har en märkbar påverkan på de resulterande värdena på utvärderade odränerade skjuvhållfastheten, samt att överlastning av sonder och val av filtertyp har liten till omärkbar påverkan på resultatet.

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