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Shirzadegan, Shahin
Publikasjoner (10 av 15) Visa alla publikasjoner
Yi, C., Nordlund, E., Zhang, P., Warema, S. & Shirzadegan, S. (2020). Numerical modeling for a simulated rockburst experiment using LS-DYNA. Underground Space
Åpne denne publikasjonen i ny fane eller vindu >>Numerical modeling for a simulated rockburst experiment using LS-DYNA
Vise andre…
2020 (engelsk)Inngår i: Underground Space, ISSN 2467-9674Artikkel i tidsskrift (Fagfellevurdert) Epub ahead of print
Abstract [en]

Ground support systems are commonly used to mitigate the potential consequences of rockburst in burst prone mines. To assess the capacity of ground support systems when subjected to dynamic loading, simulated rockburst tests using blasting were conducted at the Kiruna Mine. In this study, a numerical simulation for one of the field tests was conducted using the LS-DYNA code to investigate the dynamic response of the ground support systems including shotcrete and rockbolts. The numerical results showed a similar particle vibration pattern and a crack pattern to those of the field measurements. The effects of the detonator position and the charge configuration on the dynamic response of ground support systems are also discussed. Numerical results indicated that the peak particle vibrations on the tested panel increase along the direction of detonation propagation. It is difficult to use different charge concentrations in one borehole to investigate the effect of different dynamic loads on the dynamic response of support systems. Numerical results also indicated that 2D numerical modeling for simulated rockburst experiments could overestimate the dynamic response of ground support systems.

sted, utgiver, år, opplag, sider
Tongji University and Tongji University Press., 2020
Emneord
Simulated rockburst experiments, Ground support systems, Numerical modeling
HSV kategori
Forskningsprogram
Gruv- och berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-77828 (URN)10.1016/j.undsp.2019.11.002 (DOI)2-s2.0-85084697682 (Scopus ID)
Tilgjengelig fra: 2020-02-24 Laget: 2020-02-24 Sist oppdatert: 2020-05-28
Shirzadegan, S., Nordlund, E. & Zhang, P. (2016). In-situ dynamic testing of rock support at LKAB Kiirunavaara mine (ed.). In: (Ed.), E . Nordlund, T.H. Jones and A. Eitzenberger (eds) (Ed.), Proceedings of the 8th International Symposium on Ground Support in Mining and Underground Construction: . Paper presented at Ground Support 2016 : 11/09/2016 - 14/09/2016.
Åpne denne publikasjonen i ny fane eller vindu >>In-situ dynamic testing of rock support at LKAB Kiirunavaara mine
2016 (engelsk)Inngår i: Proceedings of the 8th International Symposium on Ground Support in Mining and Underground Construction / [ed] E . Nordlund, T.H. Jones and A. Eitzenberger (eds), 2016Konferansepaper, Publicerat paper (Fagfellevurdert)
Abstract [en]

A series of large scale dynamic tests were conducted at the LKAB Kiirunavaara mine using explosives to generate the dynamic load on the support system. This was done with the aim of developing a testing methodology for in-situ testing of ground support. Furthermore, the response of the installed rock support system to strong dynamic loading was evaluated. The results of the Tests 1, 2, 3, 4 and 5 indicated that the relation between the burden and the used amount of explosive had a vital role in either reducing or involving the effect of the detonation gases in the test results. Higher peak particle velocities were measured compared to those of similar large scale tests carried out in other countries. However, the level of induced damage in Tests 1 and 2 was limited to a fractured zone behind the support system while in Tests 4 and 5 the burden was unexpectedly destroyed. Based on the test results and preliminary numerical analysis, a modified test (Test 6) was designed at the same mine. The aim was to avoid the unexpected damage of burden as was observed in earlier tests, and to modify the dynamic loading leading to increase the depth of fractured zone and if possible pushing the support system beyond its limit. Results indicated that a larger fractured zone compare to earlier tests was developed behind the support system while the installed support system was still functional. Evidence from the damage to the tested cross-cuts in Test 6 indicated a reduction of radial cracks that provide access for the gas expansion. The results indicated that the installed support system, designed for dynamic conditions, performed well under the loading conditions which can cause ejection

Emneord
s
HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-61132 (URN)978-91-7583-804-5 (ISBN)
Konferanse
Ground Support 2016 : 11/09/2016 - 14/09/2016
Tilgjengelig fra: 2016-12-19 Laget: 2016-12-19 Sist oppdatert: 2017-11-24bibliografisk kontrollert
Shirzadegan, S., Nordlund, E. & Zhang, P. (2016). Large scale dynamic testing of rock support at Kiirunavaara: Improved test design (ed.). Tunnelling and Underground Space Technology, 59, 183-198
Åpne denne publikasjonen i ny fane eller vindu >>Large scale dynamic testing of rock support at Kiirunavaara: Improved test design
2016 (engelsk)Inngår i: Tunnelling and Underground Space Technology, ISSN 0886-7798, E-ISSN 1878-4364, Vol. 59, s. 183-198Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Based on the test results and preliminary numerical analysis of four large scale dynamic testing of rock support (Tests 1, 2, 4, and 5), a modified test (Test 6) was designed at LKAB Kiirunavaara underground mine. The aim of the modified design was to avoid the unexpected damage of burden as was observed in earlier tests, and to modify the dynamic loading leading to increase the depth of fractured zone and if possible pushing the support system beyond its limit. In this test, ground motion measurements were conducted using accelerometers, fracture investigations were made using an inspection borehole camera, and ground motion imaging and laser scanning were performed before and after blast. In Test 6, the columns of explosive were located in the middle of a pillar between two cross-cuts one supported by a rock support for seismic conditions, and the other supported by only plain shotcrete. Results indicated that a larger fractured zone compare to earlier tests was developed behind the support system while the installed support system was still functional. In cross-cut without support system, the ejection of blocks of rock from the test wall was observed. Evidence from two cross-cuts indicated a reduction of radial cracks that provide access for the gas expansion. Furthermore, the performance of the rock support was investigated by comparing with the results from the unsupported cross-cut. The results indicated that the installed support system, designed for dynamic conditions, performed well under the loading conditions which can cause ejection.

HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-13813 (URN)10.1016/j.tust.2016.07.005 (DOI)000384774700019 ()2-s2.0-84979255949 (Scopus ID)d1a34f22-92de-4746-8678-8403d7fe9c0d (Lokal ID)d1a34f22-92de-4746-8678-8403d7fe9c0d (Arkivnummer)d1a34f22-92de-4746-8678-8403d7fe9c0d (OAI)
Merknad

Validerad; 2016; Nivå 2; 20160815 (andbra)

Tilgjengelig fra: 2016-09-29 Laget: 2016-09-29 Sist oppdatert: 2018-07-10bibliografisk kontrollert
Shirzadegan, S., Nordlund, E. & Zhang, P. (2016). Large Scale Dynamic Testing of Rock Support System at Kiirunavaara Underground Mine (ed.). Paper presented at . Rock Mechanics and Rock Engineering, 49(7), 2773-2794
Åpne denne publikasjonen i ny fane eller vindu >>Large Scale Dynamic Testing of Rock Support System at Kiirunavaara Underground Mine
2016 (engelsk)Inngår i: Rock Mechanics and Rock Engineering, ISSN 0723-2632, E-ISSN 1434-453X, Vol. 49, nr 7, s. 2773-2794Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

A series of five large scale dynamic tests were conducted at the LKAB Kiirunavaara mine using explosives to generate the dynamic load on the support system. This was done with the aim of developing a testing methodology for in situ testing of ground support. Furthermore, the response of the installed rock support system to strong dynamic loading was evaluated. The tests included ground motion measurements, fracture investigation, ground and support motion imaging, as well as deformation measurements. The results indicated that the relation between the burden and the used amount of explosive had a vital role in either reducing or involving the effect of the detonation gases in the test results. In addition, the type of explosive which was used in the tests had a great impact on minimising the gas expansion effects. Higher peak particle velocities were measured compared to those of similar large scale tests carried out in other countries. However, the level of induced damage was limited to a fractured zone behind the support system and propagation of cracks in the shotcrete. Measured peak particle velocities were used to calculate the kinetic energy transmitted to the fractured zone of the test wall. The energy absorption by the Swellex, reinforced shotcrete and weld mesh was estimated by measuring the elongation/deflection of the support elements and relating these measurements to previously conducted laboratory tests. The comparison of maximum estimated energy absorbed by support system with the maximum estimated kinetic energy indicated that as the support system is still functional, the energy is partly reflected back to the surrounding rock. The results of the measurements in Tests 1, 2, 4 and 5 are presented in this paper and the methodology used to design the tests is discussed.

HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-9664 (URN)10.1007/s00603-016-0939-7 (DOI)000379015700018 ()2-s2.0-84961207075 (Scopus ID)8550fb71-5139-44c2-a2eb-ec06d447323b (Lokal ID)8550fb71-5139-44c2-a2eb-ec06d447323b (Arkivnummer)8550fb71-5139-44c2-a2eb-ec06d447323b (OAI)
Merknad
Validerad; 2016; Nivå 2; 20160321 (andbra)Tilgjengelig fra: 2016-09-29 Laget: 2016-09-29 Sist oppdatert: 2018-07-10bibliografisk kontrollert
Yi, C., Zhang, P., Nordlund, E., Shirzadegan, S. & Nyberg, U. (2016). Numerical modelling of dynamic response of underground openings under blasting based on field tests (ed.). In: (Ed.), E. Nordlund, T.H. Jones and A. Eitzenberger (eds) (Ed.), Proceedings of the 8th International Symposium on Ground Support in Mining and Underground Construction: . Paper presented at Ground Support 2016 : 11/09/2016 - 14/09/2016.
Åpne denne publikasjonen i ny fane eller vindu >>Numerical modelling of dynamic response of underground openings under blasting based on field tests
Vise andre…
2016 (engelsk)Inngår i: Proceedings of the 8th International Symposium on Ground Support in Mining and Underground Construction / [ed] E. Nordlund, T.H. Jones and A. Eitzenberger (eds), 2016Konferansepaper, Publicerat paper (Fagfellevurdert)
Abstract [en]

In order to assess the capacity of ground support systems when subjected to dynamic loading, simulated rockburst tests by using blasting have been conducted at LKAB Kiirunavaara underground mine. In this paper, a numerical simulation for one of the field tests is conducted using LS-DYNA code to numerically investigate the effect of the different aspects of the charge design including the initiation point and the geometry on the test results. In the simulation, an explosive material model is used to model the detonation of explosive used in field tests and the Riedel-Hiermaier -Thoma (RHT) material model is used to model the dynamic response of the rock mass. The decoupling effect between the explosive and the wall of borehole is also taken into account in the model. The numerical results show a similar particle vibration pattern and a crack pattern to those of the field measurment. The effects of the position of the initiation point and the charge structure on the dynamic response of rock mass are also discussed. The results can be a reference for blast design for future field tests.

HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-61089 (URN)978-91-7583-804-5 (ISBN)
Konferanse
Ground Support 2016 : 11/09/2016 - 14/09/2016
Tilgjengelig fra: 2016-12-15 Laget: 2016-12-15 Sist oppdatert: 2018-04-17bibliografisk kontrollert
Shirzadegan, S., Nordlund, E. & Zhang, P. (2015). Development of a methodology for in-situ dynamic testing of ground support (ed.). Paper presented at Bergmekanikdag 2015 : 09/03/2015. Paper presented at Bergmekanikdag 2015 : 09/03/2015.
Åpne denne publikasjonen i ny fane eller vindu >>Development of a methodology for in-situ dynamic testing of ground support
2015 (engelsk)Konferansepaper, Oral presentation only (Annet vitenskapelig)
Abstract [en]

A series of seven large scale dynamic tests were conducted at LKAB Kiruna mine using explosives in the vicinity of cross-cuts to generate dynamic load on the support system. The aim was to develop an in-situ testing method for rock support, i.e., to determine the dynamic load that causes failure to the test wall and/or support system. The methodology used to design Tests 1 to 7 is discussed in this paper and the level of damage to the test wall and support system in each test is described. Comparison of results in different test designs indicated that increasing burden and number of blasthole at the same time, increases the possibilities of obtaining more planar waves and decreases the destructive effect of detonation gases.

HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-31450 (URN)5a09cc5a-0228-4854-8477-9be825cd7081 (Lokal ID)5a09cc5a-0228-4854-8477-9be825cd7081 (Arkivnummer)5a09cc5a-0228-4854-8477-9be825cd7081 (OAI)
Konferanse
Bergmekanikdag 2015 : 09/03/2015
Merknad
Godkänd; 2015; 20150513 (shashi)Tilgjengelig fra: 2016-09-30 Laget: 2016-09-30 Sist oppdatert: 2017-11-25bibliografisk kontrollert
Shirzadegan, S. (2014). Development of a methodology for in-situ dynamic testing of ground support (ed.). (Licentiate dissertation). Paper presented at . : Luleå tekniska universitet
Åpne denne publikasjonen i ny fane eller vindu >>Development of a methodology for in-situ dynamic testing of ground support
2014 (engelsk)Licentiatavhandling, med artikler (Annet vitenskapelig)
Abstract [en]

The increasing mining depth leads to higher stress magnitudes, resulting in increased seismic activity and more seismically-induced damage. The effectiveness of the ground support system under dynamic loading conditions has therefore become of prime interest to the mining companies in order to provide safe mining conditions with a minimum of production disturbances caused by unstable infrastructure. The problems of mining-induced seismicity have necessitated the use of ground support systems which are capable of withstanding strong dynamic loads. Although there are large amounts of measurement data from the site-installed seismic systems, they cannot be used directly to design and select the appropriate support systems due to lack of control over the location and nature of the seismic source and the effect of the rock mass on the seismic waves. Large-scale tests using explosives as the seismic source have therefore become a useful method to evaluate the performance of rock support systems for seismic conditions. A series of seven large scale dynamic tests of rock support was conducted in the Kiirunavaara mine. Explosives were detonated in boreholes in the pillar between two cross-cuts in order to generate a dynamic load on the rock support system installed on the cross-cut wall. This was done with the aim to develop a testing methodology for in-situ testing of ground support. Furthermore, the response of the installed support system to strong dynamic loading was also evaluated. The tests included ground motion measurements, fracture investigation, ground and support motion imaging, as well as the deformation measurements. The results of the measurements in Tests 1 to 7 are presented and the methodology used to design the tests is discussed. The results indicated that the relation between the burden distance and the used amount of explosive material and number of blastholes has a vital role in either reducing or involving the effect of detonation gases in test results. The large amount of data recorded during these tests will be useful for the calibration of more advanced numerical models. The energy absorption by the Swellex Mn24, 100 mm fibre reinforced shotcrete (40 kg/m3 steel fibre) and 75 mm x 75 mm weld mesh with 5.5 mm diameter was estimated and compared to that obtained from the large scale in-situ tests and laboratory tests conducted in different countries. The comprehensive ground motion data provided for the whole test wall was used to estimate the kinetic energy transmitted to the fractured zone where the support system was installed.

sted, utgiver, år, opplag, sider
Luleå tekniska universitet, 2014. s. 183
Serie
Licentiate thesis / Luleå University of Technology, ISSN 1402-1757
HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-17630 (URN)46479327-3110-450d-8ab0-7fdf89fea091 (Lokal ID)978-91-7583-167-1 (ISBN)978-91-7583-168-8 (ISBN)46479327-3110-450d-8ab0-7fdf89fea091 (Arkivnummer)46479327-3110-450d-8ab0-7fdf89fea091 (OAI)
Merknad
Godkänd; 2014; 20141113 (shashi); ¨Nedanstående person kommer att hålla licentiatseminarium för avläggande av teknologie licentiatexamen. Namn: Shahin Shirzadegan Ämne: Berganläggningsteknik/Rock Engineering Uppsats: Development of a Methodology for In-Situ Dynamic Testing of Ground Support Examinator: Professor Erling Nordlund, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Diskutant: Biträdande Professor Lars-Olof Dalhström, Chalmers tekniska högskola/NCC Teknik, Göteborg Tid: Torsdag den 18 december 2014 kl 10,00 Plats: A1545, Luleå tekniska universitetTilgjengelig fra: 2016-09-29 Laget: 2016-09-29 Sist oppdatert: 2017-11-24bibliografisk kontrollert
Shirzadegan, S., Nyberg, U., Zhang, P., Nordlund, E., Malmgren, L., Nordqvist, A. & Andersson, U. B. (2013). Large-scale dynamic testing of ground support system at the Kiirunavaara underground mine: Test 1 (ed.). Paper presented at . Luleå tekniska universitet
Åpne denne publikasjonen i ny fane eller vindu >>Large-scale dynamic testing of ground support system at the Kiirunavaara underground mine: Test 1
Vise andre…
2013 (engelsk)Rapport (Annet vitenskapelig)
sted, utgiver, år, opplag, sider
Luleå tekniska universitet, 2013
HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-23831 (URN)8987fb62-1dbf-4f1d-998a-e82065f1d46a (Lokal ID)8987fb62-1dbf-4f1d-998a-e82065f1d46a (Arkivnummer)8987fb62-1dbf-4f1d-998a-e82065f1d46a (OAI)
Merknad

För godkännande; 2013; 20130419 (shashi)

Tilgjengelig fra: 2016-09-29 Laget: 2016-09-29 Sist oppdatert: 2017-11-24bibliografisk kontrollert
Shirzadegan, S., Nyberg, U., Zhang, P., Nordlund, E., Malmgren, L., Nordqvist, A. & Andersson, U. B. (2013). Large-scale dynamic testing of ground support system at the Kiirunavaara underground mine: Tests 4 & 5 (ed.). Paper presented at . Luleå tekniska universitet
Åpne denne publikasjonen i ny fane eller vindu >>Large-scale dynamic testing of ground support system at the Kiirunavaara underground mine: Tests 4 & 5
Vise andre…
2013 (engelsk)Rapport (Annet vitenskapelig)
sted, utgiver, år, opplag, sider
Luleå tekniska universitet, 2013
HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-24951 (URN)d313ef9b-0f15-4697-9ab8-2ea589f2c6bb (Lokal ID)d313ef9b-0f15-4697-9ab8-2ea589f2c6bb (Arkivnummer)d313ef9b-0f15-4697-9ab8-2ea589f2c6bb (OAI)
Merknad

För godkännande; 2013; 20130419 (shashi)

Tilgjengelig fra: 2016-09-29 Laget: 2016-09-29 Sist oppdatert: 2017-11-24bibliografisk kontrollert
Shirzadegan, S., Nyberg, U., Zhang, P., Nordlund, E., Malmgren, L., Töyrä, J., . . . Andersson, U. B. (2013). Large-scale dynamic testing of ground support system at the Kiirunavaara underground mine: Tests 6&7 (ed.). Paper presented at . Luleå tekniska universitet
Åpne denne publikasjonen i ny fane eller vindu >>Large-scale dynamic testing of ground support system at the Kiirunavaara underground mine: Tests 6&7
Vise andre…
2013 (engelsk)Rapport (Annet vitenskapelig)
sted, utgiver, år, opplag, sider
Luleå tekniska universitet, 2013
HSV kategori
Forskningsprogram
Gruv- och Berganläggningsteknik
Identifikatorer
urn:nbn:se:ltu:diva-24288 (URN)a5c7b9ff-a2e5-4f23-81b5-1f9a26b5c22a (Lokal ID)a5c7b9ff-a2e5-4f23-81b5-1f9a26b5c22a (Arkivnummer)a5c7b9ff-a2e5-4f23-81b5-1f9a26b5c22a (OAI)
Merknad

För godkännande; 2013; 20130419 (shashi)

Tilgjengelig fra: 2016-09-29 Laget: 2016-09-29 Sist oppdatert: 2017-11-24bibliografisk kontrollert
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