This paper reports the results of load and resistance factor design (LRFD) calibration for pullout limit states for geogrid reinforced soil walls owing to soil self-weight loading plus permanent uniform surcharge. The calibration method uses bias statistics to account for prediction accuracy of the deterministic models for reinforcement load and pullout capacity, and random variability in input parameters. New revised design models are proposed to improve load/resistance prediction accuracy based on current design manual established by Public Work Research Center of Japan. And load and resistance factors are proposed that give a uniform probability of failure of 1%.
{"title":"Revised Design Models for Geogrid Reinforced Soil Walls and LRFD Calibration","authors":"Y. Miyata, R. Bathurst","doi":"10.2472/JSMS.65.40","DOIUrl":"https://doi.org/10.2472/JSMS.65.40","url":null,"abstract":"This paper reports the results of load and resistance factor design (LRFD) calibration for pullout limit states for geogrid reinforced soil walls owing to soil self-weight loading plus permanent uniform surcharge. The calibration method uses bias statistics to account for prediction accuracy of the deterministic models for reinforcement load and pullout capacity, and random variability in input parameters. New revised design models are proposed to improve load/resistance prediction accuracy based on current design manual established by Public Work Research Center of Japan. And load and resistance factors are proposed that give a uniform probability of failure of 1%.","PeriodicalId":17366,"journal":{"name":"journal of the Japan Society for Testing Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81682668","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}
Kaoru Tanaka, Tadashi Chuman, K. Nishida, Miura Toshihiko, Yuki Yamada, Takanobu Sato
Iron powder mixing is one of the methods of remediating soil contaminated with volatile organic compounds (VOCs). Iron powder dechlorinates VOCs by reduction. This method has been adopted widely because its can remediate with a relatively short time and can be applied to various type of soil. Iron powder is usually supplied into contaminated soil as slurry mixed iron powder with a thickener water solution,therefore there was a problem that ground foundation becomes weaker after work. In order to control ground strength after remediation,we have developed the new method which consists of highly-concentrated iron powder slurry using specific thickener and forming agent making bubbles which tend to broke after work. This new method reduces the water addition amount to 1/5 of conventional method,so make possible to restrain that the ground becomes weaker. Laboratory tests select the kind and contents of thickener and forming agent. Field experiments confirmed that the mixing and digging performance is secured and ground strength after work.
{"title":"Development of In-Situ Iron Powder Mixing Treatment with Air Bubbles Using Deep Mixing Method","authors":"Kaoru Tanaka, Tadashi Chuman, K. Nishida, Miura Toshihiko, Yuki Yamada, Takanobu Sato","doi":"10.2472/jsms.65.62","DOIUrl":"https://doi.org/10.2472/jsms.65.62","url":null,"abstract":"Iron powder mixing is one of the methods of remediating soil contaminated with volatile organic compounds (VOCs). Iron powder dechlorinates VOCs by reduction. This method has been adopted widely because its can remediate with a relatively short time and can be applied to various type of soil. Iron powder is usually supplied into contaminated soil as slurry mixed iron powder with a thickener water solution,therefore there was a problem that ground foundation becomes weaker after work. In order to control ground strength after remediation,we have developed the new method which consists of highly-concentrated iron powder slurry using specific thickener and forming agent making bubbles which tend to broke after work. This new method reduces the water addition amount to 1/5 of conventional method,so make possible to restrain that the ground becomes weaker. Laboratory tests select the kind and contents of thickener and forming agent. Field experiments confirmed that the mixing and digging performance is secured and ground strength after work.","PeriodicalId":17366,"journal":{"name":"journal of the Japan Society for Testing Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78746463","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}
T. Shinko, Takashi Nakamura, N. Fujimura, Yasutaka Nakata
Low-cycle fatigue tests of SUS316NG austenitic stainless steel were conducted for several strain ranges (0.76, 1.26, 2.1, 4.1, and 8.1%) in which the specimen’s surface topography was regularly measured using a laser scanning microscope. The surface topographies obtained were analyzed by frequency analysis to separate the surface relief due to persistent slip bands (PSBs) from that due to crystal grain deformation. The PSBs-induced surface relief evolution and the grain-deformation-induced one were quantitatively evaluated by using arithmetic mean roughness Ra and arithmetic mean waviness Wa, respectively. The ΔRa and ΔWa, the increments in Ra and Wa from the initial values, increased with the usage factor (UF) for each strain range. Moreover, the rates of increase in ΔRa and ΔWa with respect to UF increased with the strain range. ΔWa/ΔRa was larger for higher strain ranges. This tendency of ΔWa/ΔRa indicates that the surface relief due to grain deformation develops more prominently than that due to PSBs for larger strain ranges. The results for Ra and Wa agree with the results of surface topography observation. On the basis of these results, a method was developed for estimating the UF of fatigued material and the applied strain range by using only the measured Ra and Wa.
{"title":"Quantitative Characterization of the Changes in Surface Topography of Austenitic Stainless Steel under Low Cycle Fatigue Loading","authors":"T. Shinko, Takashi Nakamura, N. Fujimura, Yasutaka Nakata","doi":"10.2472/JSMS.64.910","DOIUrl":"https://doi.org/10.2472/JSMS.64.910","url":null,"abstract":"Low-cycle fatigue tests of SUS316NG austenitic stainless steel were conducted for several strain ranges (0.76, 1.26, 2.1, 4.1, and 8.1%) in which the specimen’s surface topography was regularly measured using a laser scanning microscope. The surface topographies obtained were analyzed by frequency analysis to separate the surface relief due to persistent slip bands (PSBs) from that due to crystal grain deformation. The PSBs-induced surface relief evolution and the grain-deformation-induced one were quantitatively evaluated by using arithmetic mean roughness Ra and arithmetic mean waviness Wa, respectively. The ΔRa and ΔWa, the increments in Ra and Wa from the initial values, increased with the usage factor (UF) for each strain range. Moreover, the rates of increase in ΔRa and ΔWa with respect to UF increased with the strain range. ΔWa/ΔRa was larger for higher strain ranges. This tendency of ΔWa/ΔRa indicates that the surface relief due to grain deformation develops more prominently than that due to PSBs for larger strain ranges. The results for Ra and Wa agree with the results of surface topography observation. On the basis of these results, a method was developed for estimating the UF of fatigued material and the applied strain range by using only the measured Ra and Wa.","PeriodicalId":17366,"journal":{"name":"journal of the Japan Society for Testing Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73380768","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}
This paper presents the details of carbonation tests conducted on cross-section cutting-off girders from a reinforced concrete (RC) bridge and proposes a method to predict the service life of an RC bridge based on the extent of deterioration associated with corrosion of the reinforcing bars due to carbonation and chloride ion attack. Service life prediction is a crucial part of systematization of bridge maintenance. Bridges are typically exposed to a range of environmental conditions over their service lives. Deterioration of RC bridges due to carbonation may occur and may have a significant effect on service life. Chloride ion attack may also influence the deterioration process if the bridge is located close to the sea. Many previous studies have examined the effect of carbonation on RC bridges. However, this paper describes the first known application of carbonation tests to cross-section cutting-off girders from a bridge. A flowchart is presented for the proposed method for predicting the service life of an RC bridge based on the extent of deterioration due to carbonation and chloride ion attack. The results show that the main factor in the deterioration of the bridge has been carbonation and that chloride ion attack has also contributed to the deterioration of the bridge. The end of the service life was defined as the point at which the cumulative amount of steel corrosion reached a critical value of Q = 75 mg/cm 2 . The service life of the bridge was predicted to be approximately 81 years (remaining life of approximately 9 years) on the sea side and mountain side and approximately 142 years (remaining life of approximately 70 years) on the bottom side. The service life for the bottom side was predicted to be longer because of repair work done on the bottom side.
{"title":"Service Life Prediction of an Aged Bridge Based on Carbonation Tests of Cross-Section Cutting-Off Girders","authors":"R. Widyawati, A. Miyamoto, H. Emoto, J. Takahashi","doi":"10.2472/JSMS.64.835","DOIUrl":"https://doi.org/10.2472/JSMS.64.835","url":null,"abstract":"This paper presents the details of carbonation tests conducted on cross-section cutting-off girders from a reinforced concrete (RC) bridge and proposes a method to predict the service life of an RC bridge based on the extent of deterioration associated with corrosion of the reinforcing bars due to carbonation and chloride ion attack. Service life prediction is a crucial part of systematization of bridge maintenance. Bridges are typically exposed to a range of environmental conditions over their service lives. Deterioration of RC bridges due to carbonation may occur and may have a significant effect on service life. Chloride ion attack may also influence the deterioration process if the bridge is located close to the sea. Many previous studies have examined the effect of carbonation on RC bridges. However, this paper describes the first known application of carbonation tests to cross-section cutting-off girders from a bridge. A flowchart is presented for the proposed method for predicting the service life of an RC bridge based on the extent of deterioration due to carbonation and chloride ion attack. The results show that the main factor in the deterioration of the bridge has been carbonation and that chloride ion attack has also contributed to the deterioration of the bridge. The end of the service life was defined as the point at which the cumulative amount of steel corrosion reached a critical value of Q = 75 mg/cm 2 . The service life of the bridge was predicted to be approximately 81 years (remaining life of approximately 9 years) on the sea side and mountain side and approximately 142 years (remaining life of approximately 70 years) on the bottom side. The service life for the bottom side was predicted to be longer because of repair work done on the bottom side.","PeriodicalId":17366,"journal":{"name":"journal of the Japan Society for Testing Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74740625","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}
Lumbers must be dried to stabilize their shape, to strengthen, and to prevent corrosion and discoloration before using. Since dehydration usually occurs from outer surface, moisture content in inner layers becomes higher than that of outside. Therefore, higher moisture gradient which may cause unexpected deformation and cracks in materials can be seen after drying. Today, there are some non-destructive techniques to measure moisture content but it is difficult to measure moisture gradient in the thickness direction without sectioning. This study aims to propose an estimation method of moisture slope for whole log based on the eigen-strain methodology in which three-dimensional residual stress distributions can be evaluated from released strains on surface. In the proposed method, shrinkage by dehydration is expressed by eigen-stains which are estimated by an inverse analysis from released strains by strain gauges in processing. When released strains due to moisture gradient are obtained in lumber processing of necessity, the process of this method can be regarded as nondestructive, essentially. In order to prove the effectiveness of this method, numerical simulations were carried out for a log with moisture gradient by using FEM (Finite Element Method). In this analysis, a split liner for prevent splitting was conducted to a log to measure released strains on surface. Moisture gradient could be estimated accurately from released strains when moisture gradient in the thickness direction was relatively steep. However, estimation accuracy became poorer when slope of moisture gradient was relatively moderate. In order to improve the estimation accuracy, a log was split in sequential processes and a formulation was attempted by consolidation those sequential histories. And, estimation accuracy could be improved successfully by adopting the sequential manner.
{"title":"Proposal of an estimation method of moisture gradient in lumbers based on the eigen-strain methodology","authors":"M. Ogawa, Jin Miyazawa","doi":"10.2472/JSMS.64.362","DOIUrl":"https://doi.org/10.2472/JSMS.64.362","url":null,"abstract":"Lumbers must be dried to stabilize their shape, to strengthen, and to prevent corrosion and discoloration before using. Since dehydration usually occurs from outer surface, moisture content in inner layers becomes higher than that of outside. Therefore, higher moisture gradient which may cause unexpected deformation and cracks in materials can be seen after drying. Today, there are some non-destructive techniques to measure moisture content but it is difficult to measure moisture gradient in the thickness direction without sectioning. This study aims to propose an estimation method of moisture slope for whole log based on the eigen-strain methodology in which three-dimensional residual stress distributions can be evaluated from released strains on surface. In the proposed method, shrinkage by dehydration is expressed by eigen-stains which are estimated by an inverse analysis from released strains by strain gauges in processing. When released strains due to moisture gradient are obtained in lumber processing of necessity, the process of this method can be regarded as nondestructive, essentially. In order to prove the effectiveness of this method, numerical simulations were carried out for a log with moisture gradient by using FEM (Finite Element Method). In this analysis, a split liner for prevent splitting was conducted to a log to measure released strains on surface. Moisture gradient could be estimated accurately from released strains when moisture gradient in the thickness direction was relatively steep. However, estimation accuracy became poorer when slope of moisture gradient was relatively moderate. In order to improve the estimation accuracy, a log was split in sequential processes and a formulation was attempted by consolidation those sequential histories. And, estimation accuracy could be improved successfully by adopting the sequential manner.","PeriodicalId":17366,"journal":{"name":"journal of the Japan Society for Testing Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81911037","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}
{"title":"Ni基単結晶超合金のき裂先端変形挙動に及ぼすγ/γ'複合組織の影響","authors":"Y. Mukai, H. Kagawa, M. Sakaguchi, M. Okazaki","doi":"10.2472/JSMS.64.120","DOIUrl":"https://doi.org/10.2472/JSMS.64.120","url":null,"abstract":"","PeriodicalId":17366,"journal":{"name":"journal of the Japan Society for Testing Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86854902","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}
H. Akashi, Takuro Mori, A. Tabuchi, Iwao Miyoshi, Kento Takuma
Construction of wooden check dams in Kyoto prefecture started in 1999, and over 130 wooden dams had been constructed as of 2013. However, these wooden check dams were constructed using members with no preservative treatment, and such members are inevitably subject to a decrease in strength due to deterioration over time. Therefore, in order to maintain wooden check dams, it is essential to evaluate the strength and durability of members in field inspections, to acquire data on secular changes in the strength of the members, and to develop techniques to estimate their strength. Accordingly, we conducted bending strength testing of members sampled from existing wooden check dams and measured them with Pilodyn and Resistograph tests. As a result, we found a negative correlation between the Pilodyn and Resistograph measurements and the bending strength. This result suggests that it will be possible to estimate the bending strength of the members in field inspections by using these techniques designed to measure the deterioration of the members. It was also found that members of wooden check dams tend to undergo deterioration faster at the dam wings or the crest of dam wings than at the dam bodies or the spillway crests, and that the rate of such deterioration varies depending on the wooden check dam.
{"title":"Bending Strength of Members in Existing Wooden Check Dams","authors":"H. Akashi, Takuro Mori, A. Tabuchi, Iwao Miyoshi, Kento Takuma","doi":"10.2472/JSMS.64.387","DOIUrl":"https://doi.org/10.2472/JSMS.64.387","url":null,"abstract":"Construction of wooden check dams in Kyoto prefecture started in 1999, and over 130 wooden dams had been constructed as of 2013. However, these wooden check dams were constructed using members with no preservative treatment, and such members are inevitably subject to a decrease in strength due to deterioration over time. Therefore, in order to maintain wooden check dams, it is essential to evaluate the strength and durability of members in field inspections, to acquire data on secular changes in the strength of the members, and to develop techniques to estimate their strength. Accordingly, we conducted bending strength testing of members sampled from existing wooden check dams and measured them with Pilodyn and Resistograph tests. As a result, we found a negative correlation between the Pilodyn and Resistograph measurements and the bending strength. This result suggests that it will be possible to estimate the bending strength of the members in field inspections by using these techniques designed to measure the deterioration of the members. It was also found that members of wooden check dams tend to undergo deterioration faster at the dam wings or the crest of dam wings than at the dam bodies or the spillway crests, and that the rate of such deterioration varies depending on the wooden check dam.","PeriodicalId":17366,"journal":{"name":"journal of the Japan Society for Testing Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85942189","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}
K. Fujiyama, K. Harada, A. Ogawa, Hirohisa Kimachi
{"title":"EBSD Analysis of Grain Strain Distribution for Creep Damaged SUS304HTB","authors":"K. Fujiyama, K. Harada, A. Ogawa, Hirohisa Kimachi","doi":"10.2472/JSMS.64.88","DOIUrl":"https://doi.org/10.2472/JSMS.64.88","url":null,"abstract":"","PeriodicalId":17366,"journal":{"name":"journal of the Japan Society for Testing Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82379910","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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