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Yu Saito - One of the best experts on this subject based on the ideXlab platform.

  • correction to supply ranges of stone blocks used in Masonry Bridges and their construction period along the east royal road in the khmer empire cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’etape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’etape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

  • Supply ranges of stone blocks used in Masonry Bridges and their construction period along the East Royal Road in the Khmer Empire, Cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’étape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’étape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

  • Supply ranges of stone blocks used in Masonry Bridges and their construction period along the East Royal Road in the Khmer Empire, Cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’etape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’etape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

Etsuo Uchida - One of the best experts on this subject based on the ideXlab platform.

  • correction to supply ranges of stone blocks used in Masonry Bridges and their construction period along the east royal road in the khmer empire cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’etape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’etape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

  • Supply ranges of stone blocks used in Masonry Bridges and their construction period along the East Royal Road in the Khmer Empire, Cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’étape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’étape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

  • Supply ranges of stone blocks used in Masonry Bridges and their construction period along the East Royal Road in the Khmer Empire, Cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’etape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’etape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

Luigi Gambarotta - One of the best experts on this subject based on the ideXlab platform.

  • lower bound limit analysis of Masonry Bridges including arch fill interaction
    Engineering Structures, 2007
    Co-Authors: Andrea Cavicchi, Luigi Gambarotta
    Abstract:

    Abstract Collapse tests on full and model scale Masonry Bridges have shown the structural role of fill and spandrels, which has to be taken into account to obtain realistic evaluations of the load carrying capacity of existing Bridges. A plane model of multi-span Masonry bridge is proposed in which the vault–fill interaction effects are considered, whose lower bounds on collapse load are obtained by a finite element application of the lower bound theorem of limit analysis. Arches and piers are modelled as beams made up of no tension, ductile in compression material and the fill as a cohesive-frictional material with a tension cut-off. The fill domain is discretized by triangular elements connected by interface elements in order to increase the ratio of the unknowns to the conditions of static admissibility; arches and piers are discretized by two-node straight beam elements. By linearisation of the conditions of plastic admissibility, a Linear Programming problem is formulated and lower bounds on the collapse load are obtained. The procedure is successfully applied to two example bridge models, where a comparison with the results obtained from the kinematic approach is made. The first example is a simulation of a collapse test on a single span bridge; the second concerns a multi-span bridge and highlights the capability of the procedure to describe complex interactions between the arch–pier structural system and the fill at collapse.

  • Two-dimensional finite element upper bound limit analysis of Masonry Bridges
    Computers & Structures, 2006
    Co-Authors: Andrea Cavicchi, Luigi Gambarotta
    Abstract:

    A two-dimensional model for the evaluation of the load carrying capacity of Masonry Bridges is proposed that takes into account the strengthening effects due to arch-fill interaction observed in experimental tests. Upper bounds on the collapse load and the corresponding mechanism are obtained by means of a finite element application of the Kinematic Theorem of Limit Analysis. Arches and piers are modelled as beams made up of non-tensile resistant (NTR) and ductile in compression Masonry, while the fill is represented as a cohesive-frictional material with tension cut-off. Kinematically admissible mechanisms are obtained by discretizing the fill domain with triangular elements and including velocity discontinuities in order to increase the degrees of freedom of the model and thus reduce locking; arches and piers are discretized by two-node straight beam elements. A piecewise linearization of the limit domains allows the upper bound on the collapse load and the corresponding mechanism to be obtained as a solution of a Linear Programming problem. The capabilities and the validity limits of the proposed numerical model are shown in two examples. The collapse test on a real single span bridge is simulated and discussed in the first example; a multi-span bridge is analysed in the second, where complex interactions between arches, piers and fill are obtained.

  • collapse analysis of Masonry Bridges taking into account arch fill interaction
    Engineering Structures, 2005
    Co-Authors: Andrea Cavicchi, Luigi Gambarotta
    Abstract:

    Experimental collapse tests on full and model scale Masonry Bridges have shown that fill and spandrels can strongly affect the collapse behaviour and increase the load carrying capacity. To provide a structura ld escription of the arch–fi ll interaction effects, a two-dimensional model of multi-span Masonry Bridges is develope di nw hich arches and piers are described as beam sm ade up of elastic, non-tensile resistant (NTR), ductile in compression material, and the fill as a Mohr–Coulomb m aterial modified by a tension cut-o ff under plane strain conditions. The load carrying capacity is evaluated by a finite element limit analysis procedure based on the kinematic theorem. The fill domain is discretized by triangular elements connected by interface elements in order to allow possible velocity discontinuities at common sides of adjacent triangular elements; arches and piers are discretized by two-noded straight beam elements. By linearization of the limit domains in th eg eneralized stress space, a linear programming problem is formulated and upper bounds of the collapse loads are obtained. Two examples ar ed iscussed, concerning a real single-span bridge, tested up to collapse, and a multi-span bridge. The ideal ductility assumption implicit in limit analysis is discussed by comparing the upper bound evaluations to th er esults obtained by incremental analysis in order to obtain the validity limits of the upper bound limit analysis for the proposed model. © 2005 Elsevier Ltd. All rights reserved.

  • collapse analysis of Masonry Bridges taking into account arch fill interaction
    Engineering Structures, 2005
    Co-Authors: Andrea Cavicchi, Luigi Gambarotta
    Abstract:

    Abstract Experimental collapse tests on full and model scale Masonry Bridges have shown that fill and spandrels can strongly affect the collapse behaviour and increase the load carrying capacity. To provide a structural description of the arch–fill interaction effects, a two-dimensional model of multi-span Masonry Bridges is developed in which arches and piers are described as beams made up of elastic, non-tensile resistant (NTR), ductile in compression material, and the fill as a Mohr–Coulomb material modified by a tension cut-off under plane strain conditions. The load carrying capacity is evaluated by a finite element limit analysis procedure based on the kinematic theorem. The fill domain is discretized by triangular elements connected by interface elements in order to allow possible velocity discontinuities at common sides of adjacent triangular elements; arches and piers are discretized by two-noded straight beam elements. By linearization of the limit domains in the generalized stress space, a linear programming problem is formulated and upper bounds of the collapse loads are obtained. Two examples are discussed, concerning a real single-span bridge, tested up to collapse, and a multi-span bridge. The ideal ductility assumption implicit in limit analysis is discussed by comparing the upper bound evaluations to the results obtained by incremental analysis in order to obtain the validity limits of the upper bound limit analysis for the proposed model.

  • Collapse analysis of Masonry Bridges taking into account arch–fill interaction
    Engineering Structures, 2005
    Co-Authors: Andrea Cavicchi, Luigi Gambarotta
    Abstract:

    Abstract Experimental collapse tests on full and model scale Masonry Bridges have shown that fill and spandrels can strongly affect the collapse behaviour and increase the load carrying capacity. To provide a structural description of the arch–fill interaction effects, a two-dimensional model of multi-span Masonry Bridges is developed in which arches and piers are described as beams made up of elastic, non-tensile resistant (NTR), ductile in compression material, and the fill as a Mohr–Coulomb material modified by a tension cut-off under plane strain conditions. The load carrying capacity is evaluated by a finite element limit analysis procedure based on the kinematic theorem. The fill domain is discretized by triangular elements connected by interface elements in order to allow possible velocity discontinuities at common sides of adjacent triangular elements; arches and piers are discretized by two-noded straight beam elements. By linearization of the limit domains in the generalized stress space, a linear programming problem is formulated and upper bounds of the collapse loads are obtained. Two examples are discussed, concerning a real single-span bridge, tested up to collapse, and a multi-span bridge. The ideal ductility assumption implicit in limit analysis is discussed by comparing the upper bound evaluations to the results obtained by incremental analysis in order to obtain the validity limits of the upper bound limit analysis for the proposed model.

Yuichiro Sakurai - One of the best experts on this subject based on the ideXlab platform.

  • correction to supply ranges of stone blocks used in Masonry Bridges and their construction period along the east royal road in the khmer empire cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’etape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’etape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

  • Supply ranges of stone blocks used in Masonry Bridges and their construction period along the East Royal Road in the Khmer Empire, Cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’étape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’étape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

  • Supply ranges of stone blocks used in Masonry Bridges and their construction period along the East Royal Road in the Khmer Empire, Cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’etape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’etape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

Rathborith Cheng - One of the best experts on this subject based on the ideXlab platform.

  • correction to supply ranges of stone blocks used in Masonry Bridges and their construction period along the east royal road in the khmer empire cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’etape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’etape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

  • Supply ranges of stone blocks used in Masonry Bridges and their construction period along the East Royal Road in the Khmer Empire, Cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’étape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’étape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.

  • Supply ranges of stone blocks used in Masonry Bridges and their construction period along the East Royal Road in the Khmer Empire, Cambodia
    Heritage Science, 2020
    Co-Authors: Etsuo Uchida, Yuichiro Sakurai, Rathborith Cheng, Ichita Shimoda, Yu Saito
    Abstract:

    During the Angkor period, there were five Royal Roads linking the capital city of Angkor with provincial principal cities. Seven Temples d’etape, six Fire Shrines, and 25 Masonry Bridges were constructed along the East Royal Road to Preah Khan of Kompong Svay. We conducted measurements of magnetic susceptibility and chemical composition of laterite blocks and magnetic susceptibility of sandstone blocks used for the construction of the Bridges to determine the supply ranges of the stone blocks and the construction ages based on the results obtained in this study and previous studies of Temples d’etape and Fire Shrines. The results suggest that most of the sandstone blocks for the bridge balustrades were supplied from quarries in the southeastern foothills of Kulen Mountain, but that the Bridges close to Preah Khan of Kompong Svay have sandstone balustrades supplied from nearby quarries. In contrast, cluster and principal component analyses and t-tests using data for chemical composition and magnetic susceptibility of laterite blocks revealed that there were five sources of supply. These results elucidated that the supply ranges of laterite blocks were narrower than those of the sandstone blocks. Judging from magnetic susceptibilities, supply ranges, shapes, orientations of bedding planes, and stacking methods of the stone blocks, it was concluded that the construction age of the Bridges is highly likely to have been in the early Angkor Wat period.