Diploma thesis deals with using microtunneling method in Pardubice-city. Evaluate construction of sewer and assessing the posibilities of furthert use of this technology. The work include static assessment of jacking pipes. Mathematical modeling is used in software Plaxis 8.2.

An underground installation with too much inflow can lead to dangerous consequences for around environment, therefore a well-sealed construction results in appropriate inflows. To mitigate movement of ground water table in underground constructions, it is necessary to seal the rock mass by grout injection. To fulfill the inflow requirement, cement based grouting is both practical and economical solution and is used in Sweden as permanent solution because of the good quality rock mass of Nordic countries. To achieve an effective and more economical grouting process, the method of stop criteria named GIN has been developed for underground constructions. "GIN method" is a method in formulating grouting works which provides possibility for minimizing the risk of hydro fracturing and hydro jacking in grouting process to optimize it in performance and cost of construction process. In this report the effort is testing the validity of this method in City banan project which is situated in Stockholm. Data are taken from the City banan project which is under construction by Traffikverket in Stockholm. To attain this aim, data from monitoring of grouting process was collected and Pressure and flow values were obtained and have been employed as input data in this report. After applying GIN method, results have been analyzed and discussed in detail. It has been shown that in studied cases, the theory cannot provide promising results and this method is difficult to be applicable in this project. Therefore, additional tests are needed to the exact suitable GIN number for the project.

The frictional behavior of soil-construction material interfaces is of significant importance in geotechnical engineering applications such as retaining structures, pile foundations, geosynthetic liners, and trenchless technologies. Since most failures initiate and develop on the interfaces, special attention is required to predict the capacity of these weak planes in the particular application. Pipe-jacking and microtunneling technologies are being more widely used over the past decade and there is significant interest to predict the jacking forces and jacking distances achievable in order to achieve more efficient design and construction. This study focuses on the evaluation of the frictional characteristics and factors affecting the shear strength of pipe-soil interfaces. Eight different pipes made from fiber reinforced polymer (FRP), polycrete, steel, concrete, and vitrified clay were tested in the experimental program. For this purpose, a new apparatus was designed to conduct conventional interface direct shear testing on pipes of different curvature. This device allows coupons cut from actual conduits and pipes to be tested in the laboratory under controlled conditions. The apparatus includes a double-wall shear box, the inner wall of which is interchangeable to allow for testing against surfaces of different curvatures. By considering a narrow width section, the circular interface of pipes was approximated with a surface along the axial direction and the boundary is defined by the inner box. Roughness tests were performed using a stylus profilometer to quantify the surface characteristics of the individual pipes and relate these to the interface shear behavior. The surface topography showed different degrees of variability for the different pipes. To extend the range of roughness values tested and force the failure to occur in the particulate media adjacent to the interface, two artificial pipe surfaces were created using rough sandpapers. Interface shear tests were performed using the new apparatus with air-pluviated dense specimens of Ottawa 20/30 sand. Additional tests were performed using Atlanta blasting sand to evaluate the effect of particle angularity. The effect of normal stress and relative density were also examined. The interface strength was shown to increase with surface roughness and finally reach a constant value above a certain critical roughness value, which corresponded to the internal strength of the soil itself. This represented the failure location moving from the interface into the soil adjacent to the interface. Both the strength and the shearing mechanism were thus affected by the surface topography. It was also shown that the interface shear strength was affected by particle angularity, relative density and normal stress.

Pipe jacking, has seen a rise in popularity, particularly in urban areas where infrastructure does not permit cut-and-cover methods. As pipe jacking has becomes more commonplace, engineers are pushing the limits of the technology more and more by designing longer drives in more difficult ground conditions. Lubrication is essential to reduce the frictional resistance generated at the pipe-soil interface. Even though lubrication is widely utilized, there is not a clear understanding of the conditions required to obtain the full benefit of lubrication. This dissertation focuses on bentonite slurry characteristics and interface behavior under different lubricating conditions with the goal to further the understanding of the mechanisms responsible for the large friction reductions observed in the field. An interface shear device capable of measuring interface behavior on pipe surfaces was used to perform tests under two lubricating conditions. Pipes were sheared against a mixture of sand and slurry and the effect of the slurry was quantified. In another series of tests, slurry was injected at the pipe-soil interface. An axisymmetric interface shear device was developed to further investigate the lubrication mechanism associated with injection of slurry into sand. The device was designed to inject slurry through injection ports built into a shaft displaced within a sealed sand-filled chamber. A series of tests were performed on dry sand as well as sand where water or slurry was injected during shearing. The effect of sand type and viscosity are also investigated. Findings from the experimental studies are related back to full-scale behavior with the objective of assessing the lubrication methods and their effectiveness. A rational procedure for predicting non-lubricated and lubricated jacking forces is proposed to optimize design and serve as a framework for evaluating jacking forces in the field.

During the construction of water pipeline Strelice is necessary to overcome the D1 motorway. This thesis deals with design of the motorway crossing using trenchless technologies. Combination of pipejacking and shield tunneling is chosen. Static calculation includes determination of the jacking force, proposal of the thrust block and assessment of the reinforced concrete jacking pipes.

“Real Time Grouting Control Method” is a pioneer idea informulating grouting works which provides possibility for monitoring groutingprocess in real time to optimize it to performance and cost. Currently this theoryhas been tested with data from tunnels in Stockholm. In this report the effort istesting the validity of this method in a kind of geology which is situated insouthwest of Iran. Data are taken from the Gotvand dam project which is underconstruction on Karoon River. To achieve this goal, Tests are performed inStockholm by using the cement collected from the dam site to obtain rheologicaland penetrability properties of the grout mix which is in use in Gotvand project.Pressure and flow values are recorded in during grouting and have beenemployed as input data in this report. By developing a proper application, resultshave been analysed and discussed in detail. It has been shown that in studiedcases the theory can provide promising results and this method is applicable inthis project although there is a need for site investigation and testing different kindof grout mixes to precise results and be able to drive a general conclusion. / QC 20101009

Abstract This thesis discusses strengthening foundations of historic buildings by means of pretested, end-jacked, steel piles; pretested, end-jacked drilled spiral steel piles, as well as the geotechnical and structural design of strip foundations using ultimate limit state methods. Strengthening the foundations of historic buildings is a field of engineering where every site is more or less different from another. The variation of the substructure, foundation, and soil circumstances make every case unique. Preserving heritage buildings by preventing structural decay requires know-how and suitable strengthening methods. Drilled spiral piles and jacked piles were employed as strengthening methods for St. John’s Church of Tartu, because of the sinking and uneven settlement of the building. The strengthening work at St. John’s Church was challenging due to the risk of collapse of this historic church. Underpinning with jacked piles is a preferred method for strengthening historic foundations and where drilled spiral piles were employed, the author of this thesis developed special equipment. The strengthening method employed for the tower complies with the anastylosis principle by preserving the authenticity of the structures. Old block stones are visible upon the floating piled rafts. The empty space was left to give archaeologists and engineers a chance to study the realized work “in situ” in the future. The foundation of the tower was underpinned step by step with end-jacked piles and a concrete raft poured step by step. The weight of the tower is 5 500 tons and it rests on four pillars. Every pillar rests on its own floating piled raft. This thesis proves that by means of lower and upper bound theorems a floating, piled strip-foundation can be designed geotechnically and structurally using one method based on ultimate limit state (ULS) and serviceability limit state (SLS). The method takes the following into account as geotechnical requirements: total settlement and angular distortions; and as structural requirements; admissible plastic rotations, end moments due to displacement angle, as well as control of cracking. The chosen piling methods were suitable for St. John’s Church, and the installed piles work well in addition to the old foundations. The functionality of the strengthening techniques has been verified by test piling. Furthermore, every drilled spiral pile was preloaded twice and end-jacked for soil hardening. / Tiivistelmä Tämä tutkimus käsittelee historiallisten rakennusten perustusten vahvistamista esikuormitetuilla teräksisillä puristuspaaluilla ja esikuormitetuilla, loppupuristetuilla spiraaliporapaaluilla. Tutkimus sisältää myös pitkänomaisen anturaperustuksen mitoitusmenetelmän, joka huomioi sekä murtorajatilan että käyttörajatilan vaatimukset. Historiallisten rakennusten perustusten vahvistaminen on insinööritieteen osa-alue, missä jokainen työmaa on oma, ainutlaatuinen kohteensa johtuen erilaisista maaperäolosuhteista, perustuksista ja rakenteista. Rakennuksen luonteen säilyttäminen edellyttää insinööriltä monialaista kykyä ja tietoa sopivista vahvistamismenetelmistä. Spiraaliporapaaluja ja puristuspaaluja käytettiin Johanneksen kirkon (Jaani Kirik) perustusten vahvistamisessa rakennuksen epätasaisen painumisen ja sortumisvaaran vuoksi. Perustusten vahvistamista puristuspaaluilla pidetään yleisesti parhaana menetelmänä historiallisille rakennuksille. Tämän tutkimustyön tekijä suunnitteli erikoiskaluston työtä varten kehitetylle kierrepaalulle. Anastylosis periaatteen mukaisesti käytetyssä tornin vahvistamismenetelmässä säilytettiin rakenteiden autenttisuus. Vanhat kivilatomukset ovat osittain näkyvissä. Niiden välissä oleva tyhjä tila antaa arkeologeille ja insinööreille mahdollisuuden tutustua suoritettuun työhön. Tornin perustukset vahvistettiin vaiheittain paaluilla sekä valetulla betonilaatalla. Torni painaa 5 500 tonnia ja se on neljän pilarin varassa. Jokaisella pilarilla on erillinen kelluva paalutettu laattaperustus. Tässä työssä on osoitettu, että plastisuusteorian ala- ja ylärajalauseiden avulla myötäävän kitkamaan ja myötäävän paalutuksen varaan perustettu pitkänomainen anturaperustus voidaan mitoittaa geo- ja rakenneteknisesti murto- ja käyttörajatilassa samalla menetelmällä. Menetelmä sisältää geoteknisinä vaatimuksina anturan pohjapaineen, kokonaispainuman ja kulmakiertymän (= epätasaisen painumisen) määrittämisen, rakenteellisina vaatimuksina plastisoituvien kohtien riittävän muodonmuutoskyvyn, kenttä- ja tukimomenttien, epätasaisen painumisen aiheuttamien pakkomomenttien sekä halkeamatarkastelun määrittämisen. Spiraaliporapaalujen toiminnallisuus varmistettiin koepaaluilla. Maanlujittumista varten jokainen spiraaliporapaalu koestettiin kahdella esikuormituksella ja loppupuristuksilla.

The trend of offshore wind power is bigger and bigger wind turbines. Turbines are now becoming so big that existing installation vessels no longer are feasible and new bigger installation vessels are needed. Ship owners hesitate to order new vessels worried that the rapid turbine growth will continue and make also the new vessels obsolete in a few years. This can create a bottleneck in the offshore wind market.   This thesis assignment attempts to develop a telescopic tower as an alternative way of installing offshore wind turbines. A telescopic tower can decrease overall height and COG during marine installation, giving opportunity to install the largest wind turbines also with existing vessel fleet.   The method for developing the telescopic tower is to first find the main problems and functions of the concept. A design basis based on a 12 MW reference wind turbine is developed. Based on this reference turbine different solutions to the main problems and functions are developed by creative thinking, literature research, modelling, calculations and analysis. A cost/benefit analysis is performed to investigate if there is any economic potential in the developed solution. To complete the study other installation methods and telescopic tower concepts are investigated for benchmark comparison.   The telescopic tower will have two sections. Shoulders are welded to the inner wall of the lower tower. The upper tower fit inside the lower tower and a telescopic mechanism is installed below to lift the assembly as the mechanism climb the shoulders of the lower tower. The telescopic mechanism works much like a pin and hole mechanism used for jack-up rigs. The pins engage/disengage with the shoulders by the movement of linear actuators. The vertical climbing motion is provided by hydraulic cylinders. The power source is an HPU placed on the wind turbine external platform.   To connect the upper and lower tower permanently a friction connection with long slotted holes is used. This connection is developed for assembly of onshore towers in an EU-sponsored project called Histwin. The walls of the lower and the upper tower overlap at the connection and are pressed together by pretensioned bolts to create a friction surface that hold the loads from the upper tower.   The conclusion is that the telescopic tower is technically feasible and can be installed by the existing installation vessel fleet. The economic feasibility is dependent on the specific project characteristics, but there are scenarios where the telescopic tower can have great economical upside.