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The relationship between index testing and California Bearing Ration values for natural road construction materials in South AfricaBreytenbach, Izak Johannes 15 December 2009 (has links)
The research portrayed in this dissertation aims to derive empirical means of predicting CBR values from index testing parameters and parameters calculated from them (e.g. shrinkage product). The project involved compiling a database of test results for a range of rock material types across moist and dry regions in southern Africa. The database was compiled in such a way that it represents natural gravels sampled (mostly) for construction or rehabilitation of road layer works. The database included a location description, material description, Weinert N-Value, Atterberg Limits, grading analysis and CBR values. In addition to this, the linear shrinkage product, shrinkage product, grading coefficient, grading modulus and dust ratio were calculated and also used in the analyses. All the samples were divided into two groups based on climate, as described by Weinert (1980). The data was then further sub-divided into compaction classes (95%, 98% and 100% Mod AASHTO) and within these compaction classes, each sample was assigned to a rock material group based on the classification proposed by Weinert (1980), but with minor alterations (e.g. further subdivision of pedogenic deposits). A total of 60 groups were created. Data processing was done using grading normalised to 100% passing the 37,5mm screen. In order to limit interdependency resulting from the cumulative grading, the sieve analysis results were converted to percentages retained on each sieve. This was necessary as statistical regressions often rejected datasets due to interdependency among input parameters (such as Atterberg Limits and cumulative grading). Based on the nature of the data, both stepwise linear regressions and Weibull regressions were performed. Though the Weibull regression is more suitable to the data (in theory) the linear regression could not be excluded, due to variable data. In addition, the existing model proposed by Kleyn (1955) which was derived empirically by Stephens (1988) was also retained for the analysis. In an attempt to refine Kleyn s model, the two parameters used by the method (i.e. grading modulus and plasticity index) were used in normal linear regressions in an attempt to adapt the model to specific material (and compaction) groups in the two climatic regions. More than 130 regressions were done for the final analysis (excluding experimental regressions, etc.), after restricting the predicted CBR ranges in an attempt to eliminate the prevailing data trend. The attempt proved futile, though, placing severe restrictions on the derived models. For each of the 60 groups all four methods were tested (i.e. stepwise linear regression, Weibull regression, Kleyn s model and a linear model adapted for each group based on Kleyn s model) and the most suitable model selected. A number of regressions were incomplete due to insufficient data, particularly in the groups associated with dry regions. Results proved poor and are ascribed to data variability rather than test methods. The data variability, in turn, is the result of test methods with poor reproducibility and repeatability. In short, the test methods (the CBR in particular) resulted in inconsistent data and subsequently poor results, making accurate predictions nearly impossible. / Dissertation (MSc)--University of Pretoria, 2010. / Geology / unrestricted
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Lokalisering av ytor för hantering av jord- och bergmaterial i SödertörnMorén, Linda January 2015 (has links)
Syftet med arbetet var att identifiera ytor inom Södertörn där det skulle vara möjligt att etablera materialterminaler för hantering av byggbranschens jord- och bergmaterial. Förhoppningen var att detta kunde bidra till ett planeringsunderlag för en samordnad materialförvaltning inom regionen. Behovet och nyttan av fler materialterminaler har börjat uppmärksammas, men inga studier kring vilka platser som lämpar sig för ändamålet har tidigare genomförts utifrån svenska förhållanden. För att ta reda på vilka kriterier som definierade en bra materialterminalyta genomfördes en intervjustudie där tio aktörer med anknytning till materialhanteringsbranschen intervjuades. Kriterierna översattes till geografisk information och implementerades i GIS-programmet ArcMAP där det konstruerades en kartbild vilken visualiserade de ytor som var lämpliga respektive olämpliga att använda för ändamålet. Därefter genomfördes ett exempel vilket visade hur kartunderlaget kunde användas för att göra ett första urval av potentiella platser för en terminal inom angivet avstånd från utvalda byggprojektområden. För att ytterligare bidra till planeringsunderlaget identifierades regionens nuvarande materialterminaler, även de redovisades i en geografisk bild konstruerad i ArcMAP. I stort var de intervjuade aktörerna överens om vilka kriterier en materialterminalyta bör uppfylla. De främsta tycktes vara följande; att terminalen har ett bra logistiskt läge som ger korta transporter, att den kan avskärmas från boende och andra som vistas i området, att den har liten konkurrens från andra intressen och ligger utanför miljökänsliga områden samt har en (tillräckligt) stor yta. GIS-analysen och dess resulterande kartbild visade att det fanns stora tillgängliga ytor som uppfyllde kriterierna och som potentiellt skulle kunna användas till nya materialterminaler inom Södertörn. Detta strider mot den vedertagna uppfattningen om att platsbrist är en av de största anledningarna till att terminaler inte har kunnat etableras. Alla kriterier fanns dock inte representerade i analysen, vissa visade sig nämligen vara svåra att översätta till geografisk information. Dessutom fanns det inte alltid tydliga gränser mellan när en markyta kunde användas och inte, i flera fall tycktes det bero på platsspecifika egenskaper. Antaganden och subjektiva bedömningar låg därmed delvis till grund för hur kriterierna representerades i kartbilden. Dessa antaganden och bedömningar baserades dock på intervjuer med kunniga och insatta aktörer samt relevant litteratur, resultaten bedömdes därmed som rimliga och kartbilden möjlig att använda för att få en uppfattning om potentiella materialterminalplatser. GIS-analysen med resulterande kartunderlag skulle kunna användas för att göra ett första urval av potentiella terminalplatser som sedan analyseras vidare innan slutgiltigt val. Rapporten kan användas till att få en bredare kunskap om materialterminaler, vilka kriterier och krav de bör uppfylla och hur berörda aktörer tänker kring dessa. / The purpose of this thesis was to identify areas within Stockholm’s southernmost municipalities (Södertörn) where it was possible to establish terminals where soil and rock material used within the construction industry could be stored and sorted. This should contribute to the planning of a coordinated material management in the region. The need for and usefulness of these hubs have begun to be recognized, but no studies about suitable sites based on Swedish conditions has previously been carried out. In order to find the criteria that define a favourable area for such a site ten stakeholders with connection to the material management were interviewed. The criteria were then translated into geographic information and implemented in the GIS software ArcMap, where a map visualizing the areas that were suitable respectively unsuitable for the purpose was constructed. Thereafter an example which showed how the map could be used to make an initial selection of potential sites within a specified distance from selected construction sites was carried out. In order to further contribute to a coordinated material management the region's current sites for soil and rock handling were identified, also presented in a geographical image constructed in ArcMap. Overall the interviewed stakeholders agreed about which criteria a soil and rock handling site should meet. The most important ones seemed to be the following; a good logistical location which minimizes transportation distances, possibility to shield it from residents and others staying in the area, little competition from other interests, a location outside environmentally sensitive areas, and finally, an area that is (sufficiently) large. The result showed that there existed large accessible areas that could potentially be used for the establishment of new handling sites within Södertörn, which contradict the opinion that the lack of space is one of the major reasons to that these kind of establishments can’t be established. All criteria were not represented in the map though, this since some were not possible to translate into geographic information. Moreover, clear boundaries between when an area could be used and not were sometimes lacking, it seemed to depend on site-specific characteristics. How the criteria were represented in the map was therefore partly based on assumptions and subjective judgments. Assumptions and estimates were however based on interviews with knowledgeable stakeholders and relevant literature and were therefore considered to be reasonable. The map was considered to be able to give an indication of where were soil and rock handling sites potentially could be established. The map could be used to make an initial selection of potential sites, which then can be further analysed before a final choice. The report can be used to gain a broader understanding of these kind of establishments, the criteria and requirements they must meet, and what involved stakeholders think about these.
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Engineering Geology and Geotechnical Investigation of Highwall Stability at the Proposed Terrace Opencast Coal Mine, Reddale Valley, Reefton.Lea, Joanna Mary January 2006 (has links)
This thesis presents an engineering geological and geotechnical investigation of the proposed Terrace Opencast Coalmine highwall in the Reddale Valley, Reefton. The proposed pit will target the 4-11m thick No. 4 Seam coal, which exists on the Valley floor beneath outwash gravels and Brunner Coal Measures (BCM) overburden dipping at 15-30° to the northwest. Rock coatings are providing friable sandstone units with protection from weathering in existing cut faces and may contribute to short term pit wall stability. The BCM core was divided into four geotechnical units for rock material testing purposes: unit 1 siltstone, unit 2 carbonaceous mudstone, unit 3 interbedded sandstone and carbonaceous mudstone and unit 4 loose sandstone. The average results for units 1-3 gave classifications within the medium to high porosity (9-13%) and dry density (2250-2470kg/m³) ranges, and medium to medium high slake-durability Id2 values (72-94% retained). Unit 4 (loose sandstone) recorded very low dry density (1694 kg/m³) and slake-durability Id2 (9%) average values. Strength testing confirmed that the units can be classed as weak rocks, with average UCS values of 12.8-13.7MPa for units 1-3, and for all four units Is(50) from point load testing of 0.26-0.62MPa with low cohesion values (0-6.2MPa) from triaxial testing. Friction angles from triaxial tests gave high values of 32-45°, while direct shear tests established 15° internal friction for bedding planes in carbonaceous mudstone and 37° for a high angle defect in interbedded sandstone/carbonaceous mudstone. The average Young's modulus values ranged from 0.82 to 10GPa, and Poisson's ratio between 0.39 and 0.50. Eight scanline defect surveys established that the major discontinuities in existing cut faces consist of high angle tension joints, shallow dipping bedding, and faults related to regional uplift. The defect orientations from the scanlines located in the southwest were significantly different from those in the northeast, and may be due to the faults that cross the Valley. In general the majority of defects displayed low persistence (less than 3m), were clean and tight, and had low joint roughness coefficients (JRC less than 6). Joint wall compressive strengths gave an average of 32MPa, but were affected by case-hardening on weathered faces. The results from the 8 drill holes analysed show that 37% of core was within the excellent rock quality designation class (RQD = 90-100%), while 29% was in the very poor quality rock (RQD = 0-25%). A semi-confined aquifer in the outwash gravels that will drain into the proposed pit was found to have a transmissivity of 58m²/day and hydraulic conductivity of 3.1 x 10⁻⁵ m/s. Kinematic feasibility assessment determined an optimum highwall orientation of 65° dip to 120° (dip direction), which is within at least 20° of the coal seam strike. The likelihood of planar, wedge or toppling failure depends on whether the structural conditions are similar to those encountered in the southwest or northeast scanlines, as well as the persistence of the defects present. The occurrence of small scale (less than 1m offset) 'step-up' normal faults, and the three larger faults that cross the valley, all of which are related to regional uplift, will also affect which failure mode will be kinematically feasible. Other crucial slope stability considerations include groundwater inflow from the saturated overburden and bedding parallel failures on the footwall dip slope of the pit. An investigation into case hardening on existing cut faces identified three interconnected rock coatings: iron films, lithobiontic (biological) and clay-dominated crusts. Jarosite was found at sites with abundant pyrite and the oxidation of iron may have been aided by microbial activity. A green algae inhabiting pore spaces approximately 1mm below the surface was noted beneath an iron film and it is suggested to be similar to that found in arid environments. Although lithobiontic and clay-dominated crusts did not provide the weathered surface with any additional strength, they were observed to form relatively quickly (from months to less than 5 years) and will aid short term stability by providing the batters with protection from weathering processes. This project concluded that the overburden material in the proposed highwall can be expected to behave like weak rock and in some cases (such as the loose sandstone) can be expected to have soil characteristics. Highwall stability is more likely to be affected by substantial inflows of groundwater than highly persistent joint sets. Establishment of the highwalls in their final position in the early mining stages will enable development of rock coatings that are expected to aid short and long term stability.
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Προσδιορισμός μηχανικών παραμέτρων του βραχώδους υλικού και εφαρμογή αυτών στην εκτίμηση της αντοχής και παραμορφωσιμότητας της βραχομάζαςΠαπανακλή, Στυλιανή 01 February 2008 (has links)
Αντικείμενο της παρούσας διατριβής αποτελεί η διερεύνηση των μηχανικών
παραμέτρων του βραχώδους υλικού και η εφαρμογή αυτών στην εκτίμηση της
αντοχής και παραμορφωσιμότητας της βραχομάζας. Προς την κατεύθυνση αυτή,
έγινε οριοθέτηση της μηχανικής συμπεριφοράς του βραχώδους υλικού, διατύπωση
συσχετίσεων μεταξύ των φυσικών και μηχανικών παραμέτρων του καθώς και
ημιποσοτική εκτίμηση της επίδρασης της ορυκτολογικής σύστασης στη
διαφοροποίηση της συμπεριφοράς τους. Η επεξεργασία των αποτελεσμάτων της
έρευνας έγινε μέσω ενός «Σχεσιακού Συστήματος Διαχείρισης Φυσικών και
Μηχανικών Παραμέτρων Γεωλογικών Υλικών» που σχεδιάστηκε και δημιουργήθηκε
στα πλαίσια της Διατριβής. Η έρευνα εστιάστηκε σε ιζηματογενή πετρώματα, χημικά
(ασβεστόλιθους) και κλαστικά (ψαμμίτες και ιλυόλιθοι του φλύσχη) που συναντώνται
εκτεταμένα στη Δυτική Ελλάδα καθώς επίσης και σε μεταμορφωμένα πετρώματα
(μάρμαρα).
Η δειγματοληψία των ιζηματογενών πετρωμάτων επικεντρώθηκε στους
σχηματισμούς που απαρτίζουν τις γεωτεκτονικές ζώνες των Εξωτερικών Ελληνίδων,
οι οποίες καλύπτουν το δυτικό ήμισυ του Ελλαδικού χώρου και φιλοξενούν πλήθος
τεχνικών έργων. Για τα μεταμορφωμένα, δείγματα μαρμάρων λήφθηκαν από
λατομεία της Βόρειας Ελλάδας που περιλαμβάνονται στις ζώνες των Εσωτερικών
Ελληνίδων.
Συνολικά, στα πλαίσια της έρευνας λήφθηκαν βραχώδη τεμάχη από 62 θέσεις
δειγματοληψίας από τα οποία διαμορφώθηκαν και εξετάστηκαν ως προς τις φυσικές,
δυναμικές και μηχανικές τους ιδιότητες 519 δείγματα βραχώδους υλικού. Ειδικότερα
πρόκειται για 33 θέσεις δειγματοληψίας σε ασβεστολιθικούς σχηματισμούς (271
δοκίμια), 22 θέσεις σε σχηματισμούς του φλύσχη (152 δοκίμια ψαμμίτη και 24 δοκίμια
ιλυόλιθου) και 7 θέσεις σε μάρμαρα (72 δοκίμια).
Για κάθε θέση δειγματοληψίας διαμορφώθηκαν, με εργαστηριακό
αδαμαντοτρύπανο, αδαμαντοτροχό και συσκευή λείανσης, έξι δοκίμια για τον
εργαστηριακό προσδιορισμό των φυσικών, των δυναμικών και των μηχανικών
παραμέτρων του βραχώδους υλικού. Οι εργαστηριακές δοκιμές πραγματοποιήθηκαν
σύμφωνα με τις προδιαγραφές της ISRM (1981), του ΥΠΕΧΩΔΕ (Ε102-84) καθώς και
της ASTM (D 2664 – 86, D 2938 – 86, D 2845 – 90, D 3967 – 92, D 3148 – 93).
Έτσι, συνολικά εκτελέστηκαν:
• 476 δοκιμές προσδιορισμού του πορώδους n (%), ξηρής πυκνότητας ρd
(kN/m3), κορεσμένης πυκνότητας ρsat (kN/m3), λόγου κενών e και δείκτη κενών
Iv (%).
• 249 δοκιμές προσδιορισμού της ταχύτητας διάδοσης των υπερήχων Vp και Vs
(m/sec).
• 336 δοκιμές προσδιορισμού της σκληρότητας SHV.
• 120 δοκιμές προσδιορισμού του δείκτη σημειακής φόρτισης Is(50) (MPa).
• 67 δοκιμές προσδιορισμού της αντοχής σε μοναξονική θλίψη σc (MPa) από τις
οποίες οι 58 έγιναν με σύγχρονη μέτρηση των αξονικών και πλευρικών
παραμορφώσεων για τον προσδιορισμό του μέτρου ελαστικότητας Ε και του
λόγου Poisson ν.
• 75 δοκιμές προσδιορισμού της αντοχής σε εφελκυσμό σt (MPa).
• 62 τριαξονικές δοκιμές.
Κατά την αξιολόγηση των αποτελεσμάτων των εργαστηριακών δοκιμών κρίθηκε
σκόπιμη η προετοιμασία και παρατήρηση στο μικροσκόπιο 20 λεπτών τομών που
προήλθαν από διαφορετικά δείγματα με σκοπό την καλύτερη πληροφόρηση σχετικά
με την ορυκτολογική σύσταση και τη δομή των βραχωδών υλικών που εξετάστηκαν.
Μετά το πέρας των εργαστηριακών δοκιμών τα αποτελέσματα αυτών
συγκεντρώθηκαν και αξιολογήθηκαν. Ακολούθησε στατιστική επεξεργασία από την
οποία προέκυψαν ιστογράμματα διακύμανσης των τιμών της κάθε παραμέτρου και
οριοθετήθηκε η συμπεριφορά των βραχωδών υλικών που εξετάστηκαν. Επιπλέον,
μεταξύ των διαφόρων παραμέτρων του βραχώδους υλικού σχεδιάστηκαν τα
αντίστοιχα διαγράμματα συσχέτισης και προτάθηκαν εμπειρικές σχέσεις που
συνδέουν αυτές. Επίσης, πολύ σημαντικές ποιοτικές και ημιποσοτικές εκτιμήσεις
προέκυψαν από τη συσχέτιση των παραμέτρων αντοχής με την ορυκτολογική
σύσταση των βραχωδών υλικών.
Μετά την ολοκλήρωση των εργαστηριακών δοκιμών στα πλαίσια της παρούσας
διατριβής οι παράμετροι αντοχής (αντοχή σε μοναξονική θλίψη και σταθερά mi) που
υπολογίστηκαν για το βραχώδες υλικό χρησιμοποιήθηκαν για την εκτίμηση κυρίως
της αντοχής της βραχομάζας. Για το σκοπό αυτό εκτιμήθηκε ο Γεωλογικός δείκτης
Αντοχής, GSI, σε 32 συνολικά θέσεις και προσδιορίστηκαν με τη χρήση του
προγράμματος Roclab οι παράμετροι αντοχής της βραχομάζας για τις θέσεις αυτές.
Στη συνέχεια και για να διερευνηθεί η επίδραση της διακύμανσης των παραμέτρων
του βραχώδους υλικού στη συμπεριφορά της βραχομάζας υπολογίστηκαν οι
παράμετροι αντοχής και παραμορφωσιμότητάς της με βάση τις προτεινόμενες από
τη βιβλιογραφία τιμές του mi και όχι αυτές που υπολογίστηκαν εργαστηριακά. Από τη
σύγκριση των δύο αποτελεσμάτων προέκυψαν χρήσιμα συμπεράσματα σχετικά με
τη σημασία των εργαστηριακών δοκιμών αλλά και τη σημαντική επίδραση που έχουν
οι ακριβείς τιμές των παραμέτρων του βραχώδους υλικού στην εκτίμηση της αντοχής
της βραχομάζας. / The aim of this thesis is the determination of the mechanical properties of intact
rock and their application to the estimation of the strength and deformability of the
rock mass. There has been made an attempt to set up the boundaries in rock
material behavior and to formulate empirical correlations between rock material
parameters.
In the frame of the current research a data base has been developed in order to
file all laboratory testing results that had been conducted before in Greece by the
Laboratory of Engineering Geology in University of Patras as well as the Central
Public Works Laboratory. There has been recorded a total number of 5885 entries
which correspond to an equal amount of rock specimens subjected to laboratory
tests of their physical and/or mechanical properties.
The research was focused on triaxial tests of clastic and chemical sedimentary rock specimens as well as marble rock specimens. Clastic and chemical sedimentary rocks are known to be the most widespread rock formations in Western Greece and a lot of major constructions have been made on or within these formations. Block samples were collected from 62 different sites in Greece, in order to be investigated through laboratory testing procedures. After the cutting of the samples laboratory tests were conducted in 519 cylindrical specimens. From these sites 33 were in limestones (271 specimens), 22 in flysch formations (152 sandstone specimens and 24 siltstone specimens) and 7 in marbles (72 specimens).
Laboratory core drill and saw machines were used to cut the samples and end
faces were ground in order to provide cylindrical specimens in size, shape and ends
geometries according to testing requirements. The execution of laboratory tests was in accordance with ISRM suggested methods (1981, 1986) and ASTM standards (D
2664 – 86, D 2938 – 86, D 2845 – 90, D 3967 – 92, D 3148 – 93).
More specifically the following laboratory tests were conducted:
• 476 tests for porosity n (%), ρd (kN/m3), ρsat (kN/m3), e and Iv.
• 249 tests for sound velocities (Vp and Vs).
• 336 SHV tests.
• 120 point load tests.
• 67 uniaxial compressive tests with determination of modulus of deformation E
and Poisson ratio, ν (in 58 UCS tests).
• 75 brazilian tests.
• 62 triaxial tests for rock material constant mi determination.
During the evaluation of the results of laboratory testing, 20 thin sections have
been made corresponding to different samples, in order to provide all the information
as far as the mineralogy and structure of the samples are concerned.
Statistical analyses were used in order to evaluate the test results.
The strength and deformability of the rock mass corresponding to 32 selected sites
were estimated. The Geological Strength Index, GSI and the Disturbance Factor, D were estimated in each site and used as input parameters. The values of mi, also used as input parameters, were those estimated by triaxial testing in the laboratory. Additionally, in order to evaluate the impact of the mechanical parameters of intact rock to the estimation of the strength and deformability of the rock mass, rock mass parameters
were estimated using the mi values proposed by relevant bibliographical references. As a result of the comparison between the two methods,the remarkable usefulness of the laboratory testing, as a means of preliminary design as well as the considerable impact of the mechanical parameters of the rock material
to the strength and deformability of the rock mass have been pointed out.
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Lokal samverkan för ökad cirkularitet för bergmaterial : En studie av förutsättningar för ökad cirkularitet genom samverkan mellan företag, kommuner och myndigheter / Local cooperation for increased circularity of rock materials : Local cooperation for increased circularity for rock materialsA study survey between companies, municipalities and authoritiesNäslund, Louise January 2023 (has links)
Varje år produceras ungefär 100 miljoner ton jungfruligt bergmaterial i Sverige.Generellt ligger återvinning i stort fokus idag. Trots detta och högt användande av resurser är återvinningen av bergmaterial i Sverige lägre än i många andra länder.Masshanteringen för bergmaterial är en komplex process eftersom transporterna är tunga och kan vara svåra att hantera enligt den lagstiftning som gäller. Detta leder till att massor hanteras olagligt och riskerar att skada miljö och människors hälsa. En cirkulär ekonomi är ett slutet kretslopp som fokuserar på återanvändning och minska deponi. Byggsektorn står för 60% av de globala utvunna naturresurserna och en stor mängd kan återanvändas om masshanteringen blir mer cirkulär. Cirkulär ekonomi berör hela byggsektorn därav är det svårt för en aktör att genomföra förbättringar på enskilt håll. NCC Industry AB har tagit initiativ till examensarbetet med förhoppning att de ska få en ökad återvinning och bli mer hållbara i sitt arbete. Genom lokal samverkan genomförs intervju och enkätundersökningar för att skapa öppen dialog mellan aktörerna i hanteringskedjan och få en helhetssyn över situationen. Syftet med arbetet är att bidra till ökat värde av cirkulär masshantering och att minska deponerade mängder av mineraliska produkter.Målet är att se om goda arbetssätt och strategi kan hittas genom lokal samverkan för att få en bättre cirkulär masshantering som gynnar miljön och NCC som företag.Rapporten innehåller en litteraturstudie som granskar tidigare forskning och utredningar om återvinning av massor inom bygg- och anläggningsbranschen. För att få en helhetssyn har information samlats in från olika källor. Enkäter och intervjuer har gjorts med företag, kommuner och myndigheter om deras syn på återvinning av mineraliska material.Resultat av enkät och intervju påvisar att majoriteten anser att lösningen för att öka återvinningen av bergmaterial är att samverka mellan aktörer inom regionen. Företagen konkurrerar mellan varandra i upphandlingar där beställarna inte inkluderar återvunnet material, utan det är det lägsta priset som är drivkraften i vem som vinner anbudet. Företagen önskar att beställarna föreslår återvunnet material i anbudet. Företagen försöker återvinna och återanvända överskottsmassor genom att leta strategiska ytor för återvinning. Det saknas ett system för att registrera och dela tillgång till massor mellan företag. NCCs återvinningsgrad inkluderar endast material som gått igenom en återvinningsprocess. Om återanvändning av entreprenadberg som uppstår skulle klassas som återvinning skulle NCC gå från en återvinningsgrad på 3,8 procent till 16 procent. Producenter och leverantörer upplever svårigheter i att ta ansvar för situationen. Det saknas en tydlig väg att gå från jungfruligt till återvunnet material. Frågan måste adresseras till beslutsfattare inom olika sektorer. Det kan vara svårt för enskilda iiaktörer att vidta åtgärder på egen hand men det är möjligt. Genom samverkan och öppen dialog mellan alla parter kan andelen återvunna material öka. Men någon måste våga ta första steget in i ledarrollen mot en grönare byggprocess. / Each year, approximately 100 million tons of virgin rock material is produced in Sweden. In general, recycling is a major focus today. Despite this and the high use of resources, the recycling of rock material in Sweden is lower than in many other countries. The bulk handling of rock materials is a complex process because the transports are heavy and can be difficult to handle according to the applicable legislation. This leads to masses being handled illegally and risks damaging the environment and human health. A circular economy is a closed loop that focuses on reuse and reducing landfill. The construction sector accounts for 60% of global extracted natural resources and a large amount can be reused if mass management becomes more circular. Circular economy affects the entire construction sector, therefore it is difficult for an actor to implement improvements in one place. NCC Industry AB has taken the initiative for the degree project with the hope that they will have increased recycling and become more sustainable in their work. Through local collaboration, interviews and surveys are carried out to create an open dialogue between the actors in the management chain and to get a holistic view of the situation.The purpose of the work is to contribute to increased value of circular mass handling and to reduce deposited amounts of mineral products.The goal is to see if good working methods and strategy can be found through local collaboration to get a better circular mass management that benefits the environment and NCC as a company.The report contains a literature study that examines previous research and investigations on the recycling of masses in the construction industry. In order to get a holistic view, information has been collected from various sources, including surveys and interviews with companies, municipalities and authorities about their views on the recycling of mineral materials.The results of the survey and interview show that the majority believe that the solution to increase the recycling of rock material is to cooperate between actors within the region. The companies compete with each other in procurements where the orders do not include recycled material, but it is the lowest price that is the driving force in who wins the tender. The companies wish that the customers propose recycled material in the tender. The companies try to recover and reuse surplus masses by looking for strategic areas for recycling. There is a lack of a system to register and share access to lots between companies. NCC's recycling rate includes only materials that have gone through a recycling process. If the reuse of contract rock that occurs was classified as recycling, NCC would go from a recycling rate of 3.8 percent to 16 percent.ivProducers and suppliers experience difficulties in taking responsibility for the situation. There is no clear path to go from virgin to recycled material. The issue must be addressed to decision-makers in various sectors. It can be difficult for individual actors to take measures on their own, but it is possible. Through collaboration and open dialogue between all parties, the proportion of recycled materials can increase. But someone must dare to take the first step into the leadership role towards a greener construction process.
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