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  • 松本 樹典, 武井 正孝
    土質工学会論文報告集
    1991年 31 巻 2 号 14-34
    発行日: 1991/06/15
    公開日: 2008/02/29
    ジャーナル フリー
    Stress wave theory is applied to open-ended pipe piles to clarify the effects of soil plug on the behaviour of piles during driving and static loading. Measured field data and various numerical models are reviewed ; methods are presented to calculate wave propagation in both the pile and the soil plug ; modelling is presented which takes into account the interaction between the soil plug and the pile ; also presented is simplified method to estimate the loadsettlement relation of the pipe pile in static loading. By correlating observed and calculated values in two analytical cases, the authors demonstrate that incorporation of the soil plug (modelled as a series of masses and springs) is required to correctly predict pile behaviour during driving and static loading.
  • 藤井 弘章, 国政 華菜, 難波 明代, 横溝 隆之, 西村 伸一, 島田 清, 堀 俊男, 西山 竜朗
    地盤工学会論文報告集
    2000年 40 巻 6 号 117-131
    発行日: 2000/12/15
    公開日: 2008/02/29
    ジャーナル フリー
    This study was performed to clarify which factors affected damage to tame-ike (small embankment dams for irrigation) in Hokudan Town as a result of the January 17, 1995 Hyogoken-Nambu earthquake. Factors were assumed to be : Location (
    e
    .g., Distance to Epicenter, etc.), Structure (
    e
    .g., Angle to Nearest Fault, Embankment Volume, etc.), Soil Properties of Embankment, Geology of Dam Site and History (Era of Construction, Repaired, etc.). Multivariate statistical analyses were performed for documentary data (damaged : 181, undamaged : 328). Ordinary statistical analyses were conducted for the data investigated in situ for soil properties of the embankment. The results show that the factors causing damage to dam are : (1) Nearest Fault (Nojima, Mizukoshi and D2), (2) Distance to Nearest Fault (less than 500 m), (3) Distance to Epicenter (approximately
    8
    to 14 km, which almost agrees with the location of seismic intensity
    7
    JMA), (
    4
    ) Elevation of Dam Site (higher than 100 m), (5) Embankment Volume (the greater the volume the more damage was caused), (
    6
    ) Direction of Dam Axis (normal or diagonal to the epicenter or to nearest the fault), (
    7
    ) Plan View of Dam Axis (3 or
    4
    axes), (
    8
    ) Surface Geology of Dam Site (non-cohesive soil type ground), (9) Era of Construction (prior to 1891) and (10) Soil Properties of Embankment (sand, not silty sand or gravel, penetration resistance that is 10% smaller than the undamaged dams).
  • 鹿野 美弘, 櫻井 徹朗, 小松 健一, 山田 浩之, 斉藤 謙一
    Chemical and Pharmaceutical Bulletin
    1990年 38 巻 4 号 1082-1083
    発行日: 1990/04/25
    公開日: 2008/03/31
    ジャーナル フリー
    Two new polyacetylene compounds (
    4
    E
    ,
    6
    E
    , 12
    E
    )-1-acetoxy-3-isovaleryloxytetradeca-
    4
    ,
    6
    , 12-trien-
    8
    , 10-diyn-14-ol (
    B
    ), and (
    4
    E
    ,
    6
    E
    , 12
    E
    )-1-acetoxy-3-(2-methylbutyryloxy)tetradeca-
    4
    ,
    6
    , 12-trien-
    8
    , 10-diyn-14-ol (C) have been isolated along with (
    4
    E
    ,
    6
    E
    , 12
    E
    )-1-acetoxy-3-senecioyloxytetradeca-
    4
    ,
    6
    , 12-trien-
    8
    , 10-diyn-14-ol (A) from Atractylodes Rhizome (Karabyakujutu). The structures of these compounds were determined on the basis of their spectral data.
  • 東畑 郁生, PRASAD S.K., 本多 剛, CHANDRADHARA G.P.
    地盤工学会論文報告集
    2002年 42 巻 4 号 77-88
    発行日: 2002/08/15
    公開日: 2008/02/29
    ジャーナル フリー
    The Gujarat earthquake in India occurred in January, 2001, and caused significant damage in the province of Gujarat. The Japanese Geotechnical Society sent a small reconnaissance team to the damaged region after the quake. The present text presents the report from this activity. The major attention of the team was focused on geotechnical aspects of the damage which were related to earthfill dams and harbor land fills. It was found that a significant portion of damage was concentrated in fills resting on soft natural soils. Swedish weight soundings which were conducted at two places demonstrated the existence of such a soft subsoil. From this, it was concluded that amplification of earthquake shaking as well as the permanent deformation in the soft foundation soil induced such kinds of damage as subsidence, cracking, and lateral spreading in overlying artificial fills. For the better seismic resistance of those affected fills during future earthquakes, the improvement of soft subsoil seems essential.
  • 蒋 通, 栗林 栄一
    土質工学会論文報告集
    1988年 28 巻 1 号 56-64
    発行日: 1988/03/15
    公開日: 2008/02/29
    ジャーナル フリー
    The boundary element method expanded in frequency domains is presented to analyze the dynamic interaction between an embedded flexible rectangular foundation and soil with consideration of the obliquely incident waves. Numerical results describing the influence of the flexibility of the foundation on the dynamic responses of the foundation due to obliquely incident waves indicate that the flexibility of actual foundations can diminish the reduction of translation responses and increase the rotational responses in the high frequency range. These phenomena are more conspicuous as the embedment ratio is larger and the value of the wave velocity ratio of the soil and the foundation approaches to unity. When the high frequency components of the input ground motion are important and the basement has higher flexibility (for example 2vs/1vs >0.
    4
    ), the analysis method which considers the basement as a rigid foundation may lead to unsafety estimations and the estimation of the flexibility of the foundation is necessary as analysing the effective input motion with consideration of the incident waves.
  • 山田 善一, 野田 茂
    土質工学会論文報告集
    1988年 28 巻 1 号 143-152
    発行日: 1988/03/15
    公開日: 2008/02/29
    ジャーナル フリー
  • Yukichi Yamaguchi, Jian-zhi Runan(Gen), Teruaki Nagahara
    Journal of the Physical Society of Japan
    1975年 38 巻 4 号 911-916
    発行日: 1975/04/15
    公開日: 2007/06/01
    ジャーナル 認証あり
    The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the 116mIn activity. Directional correlations are also measured for 818–1293 and 1097–1293 keV cascades. The M1-
    E
    2 mixing ratio δ, and the
    E
    0-
    E
    2 mixing ratio μk are obtained for 818.
    7
    keV
    22
    +→21+ transition to be δ=1.52
    0.22
    +0.26, and μk
    6
    .1×10
    4
    respectively. The
    E
    2 branching ratio
    B
    (
    E
    2;
    22
    +
    →0g+):
    B
    (
    E
    2;
    22
    +→21+):
    B
    (
    E
    2;
    22
    +→01+) is determined to be 0.0158:1.0:5.86.
  • Hiroyuki HIRAOKA, Naoki MORI, Ritsuo NISHIDA, Yasumasa KUWAHARA
    Bioscience, Biotechnology, and Biochemistry
    2001年 65 巻 12 号 2749-2754
    発行日: 2001年
    公開日: 2002/08/30
    ジャーナル フリー
    A mixture of two monoterpenes was obtained as the opisthonotal gland secretion from unidentified Histiogaster sp. A096 (Acari: Acaridae), and their structures were elucidated to be (
    4
    E
    )-dehydrocitrals[(2
    E
    ,
    4
    E
    )- and (2Z,
    4
    E
    )-3,
    7
    -dimethyl-2,
    4
    ,
    6
    -octatrienals] by GC/MS, GC/FT-IR, UV and 1H-NMR spectra. Both isomers of (
    4
    E
    )-dehydrocitral prepared by syntheses in
    4
    steps from 3-methyl-2-butenal with 34.2% yields (based on the ylide) were separated by column chromatography into the (2
    E
    ,
    4
    E
    )- and (2Z,
    4
    E
    )-3,
    7
    -dimethyl-2,
    4
    ,
    6
    -octatrienal. Mass spectra together with GC retention times of the purified natural (
    4
    E
    )-dehydrocitrals were identical with those of synthetic (2
    E
    ,
    4
    E
    )-3,
    7
    -dimethyl-2,
    4
    ,
    6
    -octatrienal and (2Z,
    4
    E
    )-3,
    7
    -dimethyl-2,
    4
    ,
    6
    -octatrienal. The geometry at the 2-C position of both synthetic (
    4
    E
    )-dehydrocitrals was confirmed by NOESY analyses. This is the first identification of (
    4
    E
    )-dehydrocitrals from the animal kingdom.
  • 香山 滉一郎, 森下 政夫, 張 国鋒
    粉体および粉末冶金
    2006年 53 巻 5 号 419-429
    発行日: 2006年
    公開日: 2006/12/19
    ジャーナル オープンアクセス
    The phase diagrams of the Ni-Mo-
    B
    and Ni-W-
    B
    ternary systems in the region of less than 50mol%
    B
    were constructed by thermodynamic calculation, based on the data obtained by thermodynamic measurement of the related materials. We found three ternary eutectic points and three or two ternary peritecto-eutectic points as follows:
    E1
    :L (1365K, 71.5mol%Ni-
    6
    .0mol%Mo-
    22
    .5mol%
    B
    )=(Ni)+
    Ni3B
    +
    NiMo2B2

    E2
    :L (1355K, 62.5mol%Ni-2.5mol%Mo-30.5mol%
    B
    )=
    Ni3B
    +
    Ni2B
    +
    NiMo2B2

    E3
    :L (1445K, 42.0mol%Ni-30.
    6
    mol%Mo-10.3mol%
    B
    )=(Ni)+NiMo+
    NiMo2B2

    P1:L (1812K, 34.9mol%Ni-42.3mol%Mo-
    22
    .
    8
    mol%
    B
    )+MoB=
    Mo2B
    +
    NiMo2B2

    P2:L (1633K, 42.3mol%Ni-40.
    4
    mol%Mo-17.3mol%
    B
    )+Mo=
    Mo2B
    +
    NiMo2B2

    P3:L (1812K, 53.5mol%Ni-33.
    7
    mol%Mo-12.
    8
    mol%
    B
    )+Mo=NiMo+
    NiMo2B2

    E1
    :L (1622K, 51.0mol%Ni-31.
    6
    mol%W-17.
    4
    mol%
    B
    )=(Ni)+W+
    NiW2B2

    E2
    :L (1260K, 71.0mol%Ni-
    7
    .0mol%W-
    22
    .0mol%
    B
    )=(Ni)+
    Ni3B
    +
    NiW2B2

    E3
    :L (1291K, 65.
    4
    mol%Ni-
    4
    .
    8
    mol%W-29.
    8
    mol%
    B
    )=
    Ni2B
    +
    Ni3B
    +
    NiW2B2

    P1:L (2115K, 23.
    8
    mol%Ni-43.1mol%W-33.1mol%
    B
    )+WB=
    W2B
    +
    NiW2B2

    P2:L (1657K, 48.9mol%Ni-33.1mol%W-18.0mol%
    B
    )+
    W2B
    =W+
    NiW2B2

    The calculated phase diagrams are expected to be useful for the development of new Ni-based heat-, corrosion- or wear-resistance alloys.
  • 村瀬 稔, 木股 裕子, 仲西 寿男, 小澤 一弘, 赤羽 荘資, 浅川 豊, 南澤 仁志, 上條 茂徳, 小沼 博隆
    日本食品微生物学会雑誌
    2001年 18 巻 3 号 75-81
    発行日: 2001/09/30
    公開日: 2010/07/12
    ジャーナル フリー
    At low levels, enterohemorrhagic Escherichia coli should be selectively isolated by suppressing competing microflora in meat samples. In conventional methods, MacConkey II Agar with C-T Sorbitol (cefixime-tellurite, CT-SMAC) which utilizes the ability of
    E
    . coli
    O157 to ferment sorbitol, and media containing
    E.coli
    -specific chromogenic substrates, are used for detecting
    E
    . coli
    O157.
    In this study, we compared two types of
    BD
    CHROMagarTM O157 for the isolation of enterohemorrhagic
    E
    . coli
    O157 (improved
    BD
    CHROMagarTM O157 and conventional
    BD
    CHROMagarTM O157) with CT-SMAC by using the Miles-Misra method and evaluating the recovers from ground beef and human fecal samples. The results obtained are described below:
    1. In the inoculation test with three media by the Miles-Misra method, improved
    BD
    CHROMagarTM O157 inhibited the growth of all organisms except
    E
    . coli
    O157 better than the two other media and allowed easy differentiation from
    E
    . hermannii
    , which could not be distinguished on CT-SMAC.
    2. In the
    E
    . coli
    O157 detection test for ground beef artificially inoculated with
    E
    . coli
    O157 at 1 cfu/g, the detection rate of improved
    BD
    CHROMagar TM O157 was 95%, CTSMAC 75% and conventional
    BD
    CHROMagarTM O157 40%, respectively.
    4
    . In the
    E
    . coli
    O157 detection test for
    E
    . coli
    O157 positive human fecal samples, the detection rate of improved
    BD
    CHROMagarTM O157 was 54.5%, CT-SMAC 50% and conventional
    BD
    CHROMagarTM O157
    22
    .
    7
    %, respectively.
  • ALI TABESH, HARRY G. POULOS
    地盤工学会論文報告集
    2001年 41 巻 3 号 1-16
    発行日: 2001/06/15
    公開日: 2008/02/29
    ジャーナル フリー
    In the seismic analysis of pile foundations the soil is often assumed to be an elastic material and the pressure at the soil pile interface is not limited during the analysis. This may result in a considerable error, as the computed pressure from an elastic analysis may go well beyond the ultimate lateral pressure of real soil. In fact, significant yielding at the soil-pile interface has been observed during real earthquakes, and also in laboratory tests. The yield zone is usually near the ground surface where the effect of inertial force due to the superstructure is higher. This yielding redefines the pile response, and in general cannot be ignored. In order to examine the effects of soil yielding on the internal pile response during earthquakes an approximate analysis is described in this paper which is an extension of a static method developed by the second author (1982) for the analysis of piles subjected to lateral soil movement. This method is then used to investigate the effects of soil yielding on the internal response of piles through a comparative study in which real earthquakes are used. It is shown that for strong earthquakes and heavily loaded piles the soil yielding may considerably increase the amount of maximum pile moment developed in the pile. A marked difference in the effects of yielding on the pile moment and shear is observed and discussed.
  • ABDALLAHI.HUSEIN MALKAWI, ROBERTY. LIANG
    地盤工学会論文報告集
    1996年 36 巻 3 号 67-74
    発行日: 1996/09/15
    公開日: 2008/02/29
    ジャーナル フリー
    The interaction between a penetrating shaft and the surrounding soil media under impact loading is a frequently encountered phenomenon in geotechnical engineering. Examples of such dynamic soil/shaft interaction would include dynamic pile driving, standard penetration testing (SPT), and dynamic driven rod test. Presented in this paper is a novel approach, based on the principle of dynamic system identification, which enables identification of dynamic soil-pile interaction model parameters. The analytical transfer function, relating the output stress wave forms to the input stress wave forms in the soil/shaft system, is derived using the Laplace and Fourier Transform techniques and the one-dimensional wave propagation theories. A numerical solution algorithm based on a variation of gradient method is coded into a micro-computer based program to solve the frequency-dependent soil-pile interaction parameters (Smith model) : soil damping and soil spring stiffness. To further reduce the amount of computational effort required in the solution of the frequency-dependent dynamic soil properties, it is suggested that the solution be obtained for the first-mode natural frequency of the measured stress waves. The results obtained from this simplified solution algorithm, when compared with both numerical simulations and controlled laboratory tests, are reasonably acceptable. The proposed parameter identification technique offers a viable alternative data interpretation procedure for deducing pertinent Smith model parameters used frequently in pile driving analysis.
  • Ying Jiao, Teruhiko Yoshihara, Akitami Ichihara
    Bioscience, Biotechnology, and Biochemistry
    1995年 59 巻 6 号 1032-1035
    発行日: 1995/06/23
    公開日: 2008/02/08
    ジャーナル フリー
    The syntheses of (S)-13-hydroxy-(2
    E
    ,
    4
    E
    ,
    8
    E
    )-tetradecatrienoic acid (1) and (2
    E
    ,
    4
    E
    ,
    8
    Z-tetradecatrienoic acid (2) were carried out by using the Wittig reaction as the key step. The asymmetric center at C-13 and the double bond between C-
    8
    and C-9 for natural compound 1 were reconfirmed as being of (S) configuration and
    E
    , respectively. The relationship between the structure of the unsaturated hydroxy fatty acids and their inhibitory effect on the growth of lettuce was investigated.
  • Keishi Hata, Fuyuki Sugawara, Naganori Ohisa, Saori Takahashi, Kazuyuki Hori
    Biological and Pharmaceutical Bulletin
    2002年 25 巻 8 号 1040-1044
    発行日: 2002年
    公開日: 2002/08/01
    ジャーナル フリー
    We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-
    E
    1. Sixteen phosphate buffered saline (PBS),
    8
    boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3-
    E
    1 cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (
    22E
    ,24R)-ergosta-
    7
    ,
    22
    -diene-3β,5α,
    -triol (1). 1 induced ALP activities of MC3T3-
    E
    1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MC3T3-
    E
    1 cells by 1, ergosterol (2), ergocalciferol (3), cholesta-3β,5α,
    -triol (
    4
    ),
    7
    -dehydrocholesterol (5) and cholecalciferol (
    6
    ) were tested. The enzyme activities of MC3T3-
    E
    1 cells were increased 3.0-fold by 10 μM 1 and 2.
    4
    -fold by 10 μM
    4
    . However, 2, 3, 5 and
    6
    did not induce MC3T3-
    E
    1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C-5 and/or C-
    6
    of 1 and
    4
    played an important role in their differentiation-inducing activities on MC3T3-
    E
    1 cells. Furthermore, 1 suppressed induction of MC3T3-
    E
    1 cell apoptosis by serum starvation.
  • Nobutoshi TANAKA, Ken-ichi HOSOI, Daizo TANAKA, Mimei TAKAHASHI
    Chemical and Pharmaceutical Bulletin
    1996年 44 巻 4 号 843-846
    発行日: 1996/04/15
    公開日: 2008/03/31
    ジャーナル フリー
    Chemical properties of ergosta-
    4
    ,
    6
    ,
    8
    (14),
    22
    -tetraen-3-one (1) were investigated. Though 1 is rather stable to acids or bases, it reacts easily with two moleculres of oxygen on irradiation with UV light to give
    , 9α-epidioxy-14α-hydroperoxyergosta-
    4
    ,
    7
    ,
    22
    -trien-3-one (2), which is transformed successively to
    ,
    ;
    , 9α-diepoxy-14α-hydroperoxyergosta-
    4
    ,
    22
    -dien-3-one (3) and 14α-hydroperoxy-9α-hydroxyergosta-
    4
    ,
    7
    ,
    22
    -triene-3,
    6
    -dione (
    4
    ) under these reaction conditions.
  • Suguru TAKATSUTO, Kiyomi KOBAYASHI, Tsuyoshi WATANABE, Hiroki KURIYAMA, Tokuo FURUSE
    Agricultural and Biological Chemistry
    1988年 52 巻 12 号 3217-3218
    発行日: 1988年
    公開日: 2006/04/05
    ジャーナル フリー
  • 高津戸 秀, 池川 信夫
    Chemical and Pharmaceutical Bulletin
    1984年 32 巻 5 号 2001-2004
    発行日: 1984/05/25
    公開日: 2008/03/31
    ジャーナル フリー
    Brassinolide analogues, (
    22
    R, 23R, 24R)-2α, 3α,
    22
    , 23-tetrahydroxy-
    B
    -homo-
    7
    -oxa-5α-ergostan-
    6
    -one (24-epibrassinolide) (10) and (
    22
    S, 23S, 24R)-2α, 3α,
    22
    , 23-tetrahydroxy-
    B
    -homo-
    7
    -oxa-5α-ergostan-
    6
    -one (9), were synthesized from brassicasterol (3a) in five steps and with ca. 20% overall yield. The key steps are the direct formation of (
    22
    E
    , 24R)-3α, 5-cyclo-5α-ergost-
    22
    -en-
    6
    -one (
    4
    ) from brassicasterol mesylate (3
    b
    ), the acid-catalyzed rearrangement of
    4
    to (
    22
    E
    , 24R)-5α-ergosta-2,
    22
    -dien-
    6
    -one (
    6
    ), and the Baeyer-Villiger oxidation of the tetrahydroxy 5α-ergostan-
    6
    -ones
    7
    and
    8
    .
  • 上田 穣一
    日本化学会誌(化学と工業化学)
    1974年 1974 巻 2 号 273-279
    発行日: 1974/02/10
    公開日: 2011/05/30
    ジャーナル フリー
    メチルキシレノールブルー(MXB)はアルミニウムまたはベリリウムと反応して,赤紫色または赤色の水溶栓錯体を生成する。各呈色溶液はそれぞれ,pH 2 2~2 5,波長578~583 nmおよびpH 5 9~
    6
    .5,波長513~517nmにおいて一定最大の吸光度を示す。検量線はアルミニウム濃度
    8
    ~35μ9/25mlの範囲で,またベリリウムの場合は10μ9!25 mlまで直線性を示し,吸光度0.001に対する感度はアルミニウム濃度20μ9/25mzにおいて。 oo16μ9/cm2であり ベリリウムの場合は,ooo
    8
    lzglcmsである。また,アルミニウム錯体およびベリリウム錯体の組成比をそれぞれpH 2.
    4
    およびpH
    6
    .0で検討した結果,いずれめ場合も1:1と推定された。共存イオンについては,アルミニウムの定量に対し,ガリウム塾インジウム,ビスス(III),スカンジウム,トリウム,フヅ化物イオン,シュウ酸イオンが妨害し,ベリリウムの定量に対し,アルミニウム,トリウム,クロム(III),フッ化物イオンが妨害する。なお,アルミニウムとベリリウムを同時に含む溶液について,おのおのを逐次定量する方法を検討した。
  • STEFANIA SICA, LUCA PAGANO
    SOILS AND FOUNDATIONS
    2009年 49 巻 6 号 921-939
    発行日: 2009年
    公開日: 2011/01/27
    ジャーナル フリー
    The paper illustrates theoretical and experimental procedures adopted to characterize the seismic response of earth dams by performance-based criteria. The study refers to a real case, the Camastra Dam, a zoned earth dam with vertical clay core, placed in a highly seismic zone of Southern Italy. At first, the analysis objectives have been identified along with the physical quantities needed to achieve them for characterizing dam seismic performance. A theoretical approach, consistent with the identified analysis objectives, has been later selected. The adopted approach is based on continuum mechanics and accounts for coupling between soil skeleton and pore water phase. It is also able to describe the main features of soil response under cyclic loading conditions since it implements an advanced constitutive law for the soil skeleton. Big effort has been paid to the mechanical characterization of the dam materials. In addition to data coming from the interpretation of the laboratory tests performed at the time of dam construction, in situ tests (SASW, Down Hole, DMT) have been recently carried out on the embankment and foundation soils and interpreted consistently with the requirements of the selected theoretical model. Preliminarily, the static stages of the dam lifetime have been numerically simulated to reproduce the behaviour observed in terms of cross-arm settlements and pore water pressures, in order to obtain or verify some soil parameters and initialize the state variables for the simulation of the seismic stages. A seismological study of the dam site provided the expected seismic scenarios in terms of time histories of acceleration, needed as input for the dynamic analyses. The seismic response of the Camastra Dam was finally investigated and discussed in the light of performance-based criteria.
  • LUCA PAGANO, STEFANIA SICA, POMPEO COICO
    SOILS AND FOUNDATIONS
    2009年 49 巻 6 号 909-920
    発行日: 2009年
    公開日: 2011/01/27
    ジャーナル フリー
    A crucial matter related to roads in seismic areas is to ensure viability during the post-seismic stages, especially if the road represents an important or unique way to reach towns that may be potentially hit by strong earthquakes. Verification of road viability under seismic actions requires not only safety assessment of the failure mechanisms which may jeopardize single road components (embankment, viaduct, bridge, etc.) but also evaluation of performance. Viability of a road may be compromised by an unsatisfactory response of road embankments. The vehicle flux may be, in fact, inhibited or reduced if a road embankment suffers global instability mechanisms or significant permanent displacements mainly at the contact with structural elements (
    e
    .g., viaducts, bridges) that do not move significantly. In this case the embankment permanent displacements turn out into steps or separations. The paper accounts for the different stages followed to study the seismic performance of the road embankments located along a sample road branch of about 5 km. Preliminary activities consisted in characterizing the geological area of the sample road, in selecting the potentially vulnerable embankments and in carrying out in-situ investigations to properly characterize the physical and mechanical properties of the embankments and foundation soils. A seismological study of the sample area was performed in order to characterize the reference seismic actions needed for the numerical analyses. The seismic response of the embankments was evaluated by a pseudo-dynamic approach and an advanced dynamic model. In the latter, the equations describing dynamic equilibrium and compatibility were merged with an elastoplastic combined-hardening constitutive law that properly models soil response under cyclic loads. The embankment's seismic performance was predicted in terms of permanent settlements at the embankment top surface versus the peak acceleration of the reference input motions.
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