tubaf
Thermo-mechanical coupled damage behavior of pre-damaged
rock sculptures and monuments - laboratory experiments and
numerical simulations
Thermo-mechanical coupled damage behavior of pre-damaged rock sculptures and monuments - laboratory experiments and numerical simulations
2017-09-22
[Electronic ed.]
Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola"
prv
Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", Freiberg
Geowissenschaften, Geotechnik und Bergbau
male
Jiangsu
male
male
male
Cotttaer sandstone is a quite popular material used for sculptures and monuments for almost 1,000 years. Such sculptures and monuments will be damaged after several years. The reasons for that could be different: mechanical damage due to carving by sculptors, expansion stresses due to salt crystallization or temperature change. Damages also happen sometimes after inappropriate consolidation.
Cottaer sandstone before and after consolidation was investigated by lab testing and numerical simulations in this thesis. The aim is to develop a simulation strategy which can simulate the thermomechanical coupled damage behavior at grain size level. The main research works of this thesis are as follows:
*Uniaxial compression tests, Brazilian tension tests and size effect tests were carried out to investigate the mechanical parameters of original Cottaer sandstone.
*Ultrasonic wave velocity measurement and special biaxial flexural tests were carried out to determine how deep the consolidation material penetrates and how much strength of sandstones is increased by using two different injection materials.
*A Voronoi-based numerical simulation strategy was developed which considers grain size, grain shape and pore size. Mineral components, intra- and inter-granular contacts and intra- and inter-granular fracturing were considered as well.
*Uniaxial compression tests and Brazilian tension tests of unconsolidated sandstone were simulated. This simulation strategy can capture inter- and intra-granular fracturing.
*Prediction of thermo-mechanical coupled behavior of consolidated and unconsolidated sandstone samples was performed. The simulation results show that thermal properties of grains and filled pores have influence on temperature distribution and fracture development in the sandstone. Also, thermal induced displacements are strongly influenced by boundary condition.
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Cotta, Sandstein, Konservierung, Restaurierung, Thermomechanische Eigenschaft, Thermophysikalische Eigenschaft, Elbsandsteingebirge, Steinkonservierung, Temperaturabhängigkeit, Werkstein, Verfestigung, Modellierung
Sandstein, VCM, Voronoi, grain shape, temperature
Sandstone, VCM, Voronoi, Korngestalt,Temperatur
urn:nbn:de:bsz:105-qucosa-229264
Technischen Universität Bergakademie Freiberg
dgg
Technischen Universität Bergakademie Freiberg, Freiberg
Jun
Li
1986-03-08
aut
Heinz
Konietzky
Prof. Dr.–Ing.
dgs
rev
Philipp
Blum
Prof. Dr.–Ing.
rev
Shengqi
Yang
Prof. Dr.–Ing.
rev
eng
2017-05-05
2017-09-13
born digital
Jun Li
lijun7080@163.com
doctoral_thesis