Pub Date : 2022-10-30DOI: 10.14311/cej.2022.03.0036
Long Liu, Jinyan Ma
Insufficient prestress will cause cracks in the T beam, which will influence its stiffness and bearing capacity. This paper is devoted to studying the influence of prestress levels on the bearing capacity of T beam, and then judging its working state. A full-scale model experiment is carried out on the 13 meters prestressed concrete T beam. At the same time, a nonlinear finite element model is established and verified. The experimental results show the numerical simulation results are in good agreement with the experimental results. Finally, the finite element model is used to make a simulation of the bearing capacity of T beams under different prestress levels. The mathematical relationship between prestress levels and bearing capacity is obtained based on the results of the finite element model. The relationships between the mid-span deflection and load of the experimental beam are basically the same under different prestress levels, both including three stages: elastic stage, crack development stage and failure stage. With the increase of the prestress levels, the stiffness of the experimental beam before cracking is improved significantly.
{"title":"BEARING CAPACITY OF T BEAM UNDER DIFFERENT PRESTRESS LEVELS: FULL-SCALE EXPERIMENT AND FEM ANALYSIS","authors":"Long Liu, Jinyan Ma","doi":"10.14311/cej.2022.03.0036","DOIUrl":"https://doi.org/10.14311/cej.2022.03.0036","url":null,"abstract":"Insufficient prestress will cause cracks in the T beam, which will influence its stiffness and bearing capacity. This paper is devoted to studying the influence of prestress levels on the bearing capacity of T beam, and then judging its working state. A full-scale model experiment is carried out on the 13 meters prestressed concrete T beam. At the same time, a nonlinear finite element model is established and verified. The experimental results show the numerical simulation results are in good agreement with the experimental results. Finally, the finite element model is used to make a simulation of the bearing capacity of T beams under different prestress levels. The mathematical relationship between prestress levels and bearing capacity is obtained based on the results of the finite element model. The relationships between the mid-span deflection and load of the experimental beam are basically the same under different prestress levels, both including three stages: elastic stage, crack development stage and failure stage. With the increase of the prestress levels, the stiffness of the experimental beam before cracking is improved significantly.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"50 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88490637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0026
Jundong Wu, Jiaman Li, Wei Hu
In this study, a hybrid biogeography-based multi-layer perceptron neural network (BBO-MLP) with different number of hidden layers (one up to three) was developed for predicting the California bearing capacity (CBR) value of pond ash stabilized with lime and lime sludge. To this aim, model had five variables named maximum dry density, optimum moisture content, lime percentage, lime sludge percentage and curing period as inputs, and CBR as output variable. Regarding BBO-MLP models, BBO-MLP1 has the best results, which its R2 stood at 0.9977, RMSE at 0.7397, MAE at 0.476, and PI at 0.0104. In all three developed models, the estimated CBR values specify acceptable agreement with experimental results, which represents the workability of proposed models for predicting the CBR values with high accuracy. Comparison of three developed models supply that BBO-MLP1 outperform others. Therefore, BBO-MLP1 could be recognized as proposed model.
{"title":"APPLYING BIOGEOGRAPHY-BASED MULTI-LAYER PERCEPTRON NEURAL NETWORK TO PREDICT CALIFORNIA BEARING CAPACITY VALUE OF STABILIZED POND ASH WITH LIME AND LIME SLUDGE","authors":"Jundong Wu, Jiaman Li, Wei Hu","doi":"10.14311/cej.2022.02.0026","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0026","url":null,"abstract":"In this study, a hybrid biogeography-based multi-layer perceptron neural network (BBO-MLP) with different number of hidden layers (one up to three) was developed for predicting the California bearing capacity (CBR) value of pond ash stabilized with lime and lime sludge. To this aim, model had five variables named maximum dry density, optimum moisture content, lime percentage, lime sludge percentage and curing period as inputs, and CBR as output variable. Regarding BBO-MLP models, BBO-MLP1 has the best results, which its R2 stood at 0.9977, RMSE at 0.7397, MAE at 0.476, and PI at 0.0104. In all three developed models, the estimated CBR values specify acceptable agreement with experimental results, which represents the workability of proposed models for predicting the CBR values with high accuracy. Comparison of three developed models supply that BBO-MLP1 outperform others. Therefore, BBO-MLP1 could be recognized as proposed model.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89503201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0024
Lyamine Briki, Loucif Ali Bouacida, N. Lahbari
In this study, we have developed a new cement composed by a partial substitution of the clinker with artificial pozzolans rich in silica, obtained by treatment of lignocellulosic residues, in this case, ash from rice husk. This substitution is added to the clinker with percentages ranging from 25 to 75%. These substitutions were chosen on the basis of the presence of silica which can react with portlandite (Ca(OH)2). The results obtained show that these materials have, after activation, a great pozzolanicity that allows their addition to the Portland clinker with a percentage of up to 25% of the mass of the clinker. The improvement of this reactivity is achieved by calcinating these additions at temperatures of 750°C. This significantly reduces the CO2 emissions that accompany the production of Portland cement clinker.
{"title":"USE OF CALCINATION RESIDUE FROM RICE HUSK AS A SUBSTITUTE FOR CEMENT","authors":"Lyamine Briki, Loucif Ali Bouacida, N. Lahbari","doi":"10.14311/cej.2022.02.0024","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0024","url":null,"abstract":"In this study, we have developed a new cement composed by a partial substitution of the clinker with artificial pozzolans rich in silica, obtained by treatment of lignocellulosic residues, in this case, ash from rice husk. This substitution is added to the clinker with percentages ranging from 25 to 75%. These substitutions were chosen on the basis of the presence of silica which can react with portlandite (Ca(OH)2). \u0000The results obtained show that these materials have, after activation, a great pozzolanicity that allows their addition to the Portland clinker with a percentage of up to 25% of the mass of the clinker. \u0000The improvement of this reactivity is achieved by calcinating these additions at temperatures of 750°C. This significantly reduces the CO2 emissions that accompany the production of Portland cement clinker.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"114 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77065916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0021
Djeloul Tahri
The nations of the ancient world paid special attention to the vegetation cover, and made it units of different dimensions and different arrangements, and various types of life sciences, engineering, and art were used for these units. Nature, fresh air and spacious spaces. Algerian cities in general, and their residential neighbourhoods in particular, know many aspects of deterioration, especially those associated with the preparation of external areas, foremost of which is the apparent lack of creation of green spaces within urban areas. Al-Bayadh, like other Algerian cities, complains of most of its residential neighborhoods of a complete absence of prepared green spaces, while the remaining neighborhoods contain green spaces in a deteriorating condition.
{"title":"VALUING THE URBAN SPACE ACCORDING TO THE REHABILITATION OF GREEN SPACES","authors":"Djeloul Tahri","doi":"10.14311/cej.2022.02.0021","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0021","url":null,"abstract":"The nations of the ancient world paid special attention to the vegetation cover, and made it units of different dimensions and different arrangements, and various types of life sciences, engineering, and art were used for these units. Nature, fresh air and spacious spaces. \u0000Algerian cities in general, and their residential neighbourhoods in particular, know many aspects of deterioration, especially those associated with the preparation of external areas, foremost of which is the apparent lack of creation of green spaces within urban areas. \u0000Al-Bayadh, like other Algerian cities, complains of most of its residential neighborhoods of a complete absence of prepared green spaces, while the remaining neighborhoods contain green spaces in a deteriorating condition.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87223435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0018
Y. Biks, O. Ratushnyak, A. Lyalyuk, G. Ratushnyak
The problem of the “best” choice in terms of the ecological, durable, cheap and energy-effective material of envelope construction has been considered in the paper. For the numerical assessment of the thermal performance, the MCDA techniques as Analytical Hierarchy Process (AHP) and Criteria Importance Theory (CIT) were used. There were proposed eight types of wall assemblies from a natural material, namely: Hempcrete, Adobe, Strawbale panel, Earthbag, Cordwood, SIP (plywood+ecofiber), Hempcrete+straw and Compositional building thermo-block. As a objective function for the search of the best alternative the integral index was proposed which consist of thermo-physical and economic criteria. As the thermo-physical criteria component of the index were taken the u-value of the envelope W/m2K, the dimensionless decrement factor of the envelope f and the internal areal heat capacity of the envelope k1, kJ/m2K according to ISO 13786:2017. As economic criteria of the integral index, the authors proposed the cost of the wall material Q, UAH/m2 and the mass of the wall m, kg/m2. The analysis of the conducted research has shown, that from the one hand there is no absolute “leader” in the ranking of the wall assemblies according to the proposed criteria and MCDA technique, but from the other hand by comparison of the results, there were revealed that the top three alternatives in both AHP and CIT technique are walls of “B”, “D” and “E” type with different point order, achieved in each MCDA calculation technique.
{"title":"THERMAL PERFORMANCE ASSESSMENT OF WALL ASSEMBLIES: CRITERIA IMPORTANCE THEORY AND AHP APPROACH","authors":"Y. Biks, O. Ratushnyak, A. Lyalyuk, G. Ratushnyak","doi":"10.14311/cej.2022.02.0018","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0018","url":null,"abstract":"The problem of the “best” choice in terms of the ecological, durable, cheap and energy-effective material of envelope construction has been considered in the paper. For the numerical assessment of the thermal performance, the MCDA techniques as Analytical Hierarchy Process (AHP) and Criteria Importance Theory (CIT) were used. There were proposed eight types of wall assemblies from a natural material, namely: Hempcrete, Adobe, Strawbale panel, Earthbag, Cordwood, SIP (plywood+ecofiber), Hempcrete+straw and Compositional building thermo-block. As a objective function for the search of the best alternative the integral index was proposed which consist of thermo-physical and economic criteria. As the thermo-physical criteria component of the index were taken the u-value of the envelope W/m2K, the dimensionless decrement factor of the envelope f and the internal areal heat capacity of the envelope k1, kJ/m2K according to ISO 13786:2017. As economic criteria of the integral index, the authors proposed the cost of the wall material Q, UAH/m2 and the mass of the wall m, kg/m2. The analysis of the conducted research has shown, that from the one hand there is no absolute “leader” in the ranking of the wall assemblies according to the proposed criteria and MCDA technique, but from the other hand by comparison of the results, there were revealed that the top three alternatives in both AHP and CIT technique are walls of “B”, “D” and “E” type with different point order, achieved in each MCDA calculation technique.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86291270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0019
Yanhai Yang, Liang Yue, H. Zhang, Yeol-Ho Yang
This research focuses on the equivalent relationship between cold central plant recycling mixture and hot mix asphalt. In this paper, the pavement surface condition index (PCI) was calculated by the road surface conditions investigating, which was used as the evaluation standard. The unreasonable data were removed by SPSS software. The existing decay equation of pavement performance was simplified by MATLAB, and optimized by the Marquardt and global optimization methods. The survey data were fitted nonlinearly by 1stOpt software. Ultimately, the multivariate nonlinear regression optimization equation of the equivalent thickness coefficient was established. The results show that the cold central plant recycling with the emulsified asphalt (CREA) pavement equivalent thickness coefficient is 0.587. The cold central plant recycling with the foamed asphalt (CRFA) pavement equivalent thickness coefficient is 0.632. In addition, the performance of 10 cm cold central plant recycling pavement is equivalent to 6 cm the traditional hot mix asphalt pavement. The dispersion of the CREA is greater than that of the CRFA significantly.
{"title":"EQUIVALENT THICKNESS COEFFICIENT OF COLD CENTRAL PLANT RECYCLING PAVEMENT STRUCTURE","authors":"Yanhai Yang, Liang Yue, H. Zhang, Yeol-Ho Yang","doi":"10.14311/cej.2022.02.0019","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0019","url":null,"abstract":" This research focuses on the equivalent relationship between cold central plant recycling mixture and hot mix asphalt. In this paper, the pavement surface condition index (PCI) was calculated by the road surface conditions investigating, which was used as the evaluation standard. The unreasonable data were removed by SPSS software. The existing decay equation of pavement performance was simplified by MATLAB, and optimized by the Marquardt and global optimization methods. The survey data were fitted nonlinearly by 1stOpt software. Ultimately, the multivariate nonlinear regression optimization equation of the equivalent thickness coefficient was established. The results show that the cold central plant recycling with the emulsified asphalt (CREA) pavement equivalent thickness coefficient is 0.587. The cold central plant recycling with the foamed asphalt (CRFA) pavement equivalent thickness coefficient is 0.632. In addition, the performance of 10 cm cold central plant recycling pavement is equivalent to 6 cm the traditional hot mix asphalt pavement. The dispersion of the CREA is greater than that of the CRFA significantly.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"25 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91512779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0020
Baoyang Yu, Zongguang Sun, Lin Qi
To study the deformation and failure behavior of the open-graded friction course (OGFC) before cracking at low temperatures, a four-point bending test of the trabecula was conducted, and the deformation process was monitored by the digital speckle method (DSM). The distribution law of the strain field of the trabecular specimens was analyzed. The horizontal strain field gradually changed from a uniform distribution to a strain concentration area with loading. The crack initiation time, crack initiation strain, and deformation period were obtained from the strain curve. The combination of stress reconstruction and DSM makes the stress measurement of the OGFC more authentic.
{"title":"FORMATION AND FAILURE BEHAVIOR OF OPEN-GRADED FRICTION COURSE AT LOW TEMPERATURES","authors":"Baoyang Yu, Zongguang Sun, Lin Qi","doi":"10.14311/cej.2022.02.0020","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0020","url":null,"abstract":"To study the deformation and failure behavior of the open-graded friction course (OGFC) before cracking at low temperatures, a four-point bending test of the trabecula was conducted, and the deformation process was monitored by the digital speckle method (DSM). The distribution law of the strain field of the trabecular specimens was analyzed. The horizontal strain field gradually changed from a uniform distribution to a strain concentration area with loading. The crack initiation time, crack initiation strain, and deformation period were obtained from the strain curve. The combination of stress reconstruction and DSM makes the stress measurement of the OGFC more authentic.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"85 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88233522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0027
D. Jindra, P. Hradil
This paper describes advanced numerical analysis of a simply supported reinforced concrete slab exposed to close range explosion of a TNT charge. Finite element method (FEM) has been utilized in order to conduct the analysis. Non-linear material model for concrete slab is adopted. Reinforcing bars made of basalt fibre reinforced plastic (BFRP) are considered by elastic-plastic material model. 3D numerical model has been created, and a software with explicit solver (LS-Dyna) has been used in order to conduct analyses. A simplified modelling method of the blast loading has been utilized, which is based on the consideration of the load effects as a time dependent pressure. Several cases with different mesh size or different finite element formulation are investigated. The results are compared with experimental data based on study of fellow researchers. Match between the numerical analyses and measurements is discussed and considered as satisfying.
{"title":"NUMERICAL ANALYSIS OF BFRP REINFORCED CONCRETE SLAB EXPOSED TO IMPACT LOADS","authors":"D. Jindra, P. Hradil","doi":"10.14311/cej.2022.02.0027","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0027","url":null,"abstract":"This paper describes advanced numerical analysis of a simply supported reinforced concrete slab exposed to close range explosion of a TNT charge. Finite element method (FEM) has been utilized in order to conduct the analysis. Non-linear material model for concrete slab is adopted. Reinforcing bars made of basalt fibre reinforced plastic (BFRP) are considered by elastic-plastic material model. 3D numerical model has been created, and a software with explicit solver (LS-Dyna) has been used in order to conduct analyses. A simplified modelling method of the blast loading has been utilized, which is based on the consideration of the load effects as a time dependent pressure. Several cases with different mesh size or different finite element formulation are investigated. The results are compared with experimental data based on study of fellow researchers. Match between the numerical analyses and measurements is discussed and considered as satisfying.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81610396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0028
Martin Šnorbert
This contribution deals with the urban development of the Hradčany area, within its position in the capital city, but especially within the area itself. Great emphasis is placed on historical development, as it significantly affects the current situation. Prague Castle, perceived as a historical and architectural complex, is unique in its complexity and size, we will not find a similar example in any of the surrounding countries. Prague Castle, as an important part of Hradčany, was and still is the seat of the monarch, or today the president of the Czech Republic. The development of Czech history influenced the appearance of the Castle (alternation of royal families, growth and decline in the importance of Prague, ie the Czech kingdom in Central Europe). The combination of secular and ecclesiastical power in one place is also remarkable. At the same time, it is possible to find evidence of development in the field of culture, technical conveniences, architectural and engineering arts, over the course of ten centuries. Based on archival research and the study of references, the reader is acquainted with the gradual change in the formation of the current plan of the city and the Castle. The connection between morphological assumptions and the location of first a Slavic fort, later a stone castle, is pointed out. The castle area was followed by a settlement in the sub-castle, which in the 14th century became a serf town of Hradčany. The alternation of artistic styles over the centuries and the related change in the structure and scale of buildings, but especially the panorama of Hradčany with the silhouette of the Castle, is discussed. In the end, the potential of the Hradčany area and the possibility of modernization interventions are also evaluated.
{"title":"INTERNAL AND EXTERNAL IMAGE OF HRADČANY AND PRAGUE CASTLE","authors":"Martin Šnorbert","doi":"10.14311/cej.2022.02.0028","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0028","url":null,"abstract":"This contribution deals with the urban development of the Hradčany area, within its position in the capital city, but especially within the area itself. Great emphasis is placed on historical development, as it significantly affects the current situation. Prague Castle, perceived as a historical and architectural complex, is unique in its complexity and size, we will not find a similar example in any of the surrounding countries. \u0000Prague Castle, as an important part of Hradčany, was and still is the seat of the monarch, or today the president of the Czech Republic. The development of Czech history influenced the appearance of the Castle (alternation of royal families, growth and decline in the importance of Prague, ie the Czech kingdom in Central Europe). The combination of secular and ecclesiastical power in one place is also remarkable. At the same time, it is possible to find evidence of development in the field of culture, technical conveniences, architectural and engineering arts, over the course of ten centuries. \u0000Based on archival research and the study of references, the reader is acquainted with the gradual change in the formation of the current plan of the city and the Castle. The connection between morphological assumptions and the location of first a Slavic fort, later a stone castle, is pointed out. The castle area was followed by a settlement in the sub-castle, which in the 14th century became a serf town of Hradčany. The alternation of artistic styles over the centuries and the related change in the structure and scale of buildings, but especially the panorama of Hradčany with the silhouette of the Castle, is discussed. In the end, the potential of the Hradčany area and the possibility of modernization interventions are also evaluated.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"205 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88583257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-31DOI: 10.14311/cej.2022.02.0023
Zechuang Li, Qiyuan Cai, Diankun Liu
Analyzing the change in the roughness of the shear plane under different particle composition is important to reveal the mesoscopic mechanism of strength change of coarse-grained slip zone soil. Slip zone soils were grouped according to different particle gradations and coarse particle contents for experiments. To collect shear plane coordinate data points, the customized shear plane measurement die was examined in the early stage to measure the shear plane. Then, the measured 3D data points are drawn into a 3D surface map by using the Surfer drawing software to show the actual situation of the shear plane. The shear planes were analyzed from different angles by using box plots and ice crystal flower plots. Finally, the roughness of the shear plane was quantified by the root mean square of the relative undulation (Z2). Findings indicate that the shear plane undulation characteristics of coarse-grained slip zone soil are obviously correlated with the proportion of particles with a size between 5–20 mm. Moreover, whether the gradation is good or poor has a significant effect on the shear plane characteristics. The well-graded shear plane is coarser and more undulated, whereas the poorly graded shear plane is the opposite. As the normal force increases, the undulation and roughness of the shear plane decrease. As the content of coarse particles increases, the roughness of the shear plane increases, and Z2 has a highly positive linear correlation with the coarse particle content.
{"title":"FEATURES OF THE MORPHOLOGY OF THE SHEAR FAILURE SURFACES OF COARSE-GRAINED SLIP ZONE SOILS","authors":"Zechuang Li, Qiyuan Cai, Diankun Liu","doi":"10.14311/cej.2022.02.0023","DOIUrl":"https://doi.org/10.14311/cej.2022.02.0023","url":null,"abstract":"Analyzing the change in the roughness of the shear plane under different particle composition is important to reveal the mesoscopic mechanism of strength change of coarse-grained slip zone soil. Slip zone soils were grouped according to different particle gradations and coarse particle contents for experiments. To collect shear plane coordinate data points, the customized shear plane measurement die was examined in the early stage to measure the shear plane. Then, the measured 3D data points are drawn into a 3D surface map by using the Surfer drawing software to show the actual situation of the shear plane. The shear planes were analyzed from different angles by using box plots and ice crystal flower plots. Finally, the roughness of the shear plane was quantified by the root mean square of the relative undulation (Z2). Findings indicate that the shear plane undulation characteristics of coarse-grained slip zone soil are obviously correlated with the proportion of particles with a size between 5–20 mm. Moreover, whether the gradation is good or poor has a significant effect on the shear plane characteristics. The well-graded shear plane is coarser and more undulated, whereas the poorly graded shear plane is the opposite. As the normal force increases, the undulation and roughness of the shear plane decrease. As the content of coarse particles increases, the roughness of the shear plane increases, and Z2 has a highly positive linear correlation with the coarse particle content.","PeriodicalId":21974,"journal":{"name":"Stavební obzor - Civil Engineering Journal","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87845698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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