材料
Online ISSN : 1880-7488
Print ISSN : 0514-5163
ISSN-L : 0514-5163
47 巻 , 2 号
選択された号の論文の20件中1~20を表示しています
  • 嘉門 雅史, 勝見 武, 応 長雲
    1998 年 47 巻 2 号 p. 112-115
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    The assessment and control of the geoenvironmental impact of the environmental qualities such as alkali and acid were presented. On the soil acidification caused by acid rain, negative influence on the engineering properties of the stabilized soil was experimentally clarified. The neutralization mechanism of the stabilized soil was summarized referring to the depletion step of Ca2+. The method of predicting neutralization of the stabilized soil ground was proposed. Alkali migration characteristics from the stabilized soil were also investigated referring to the buffer ability of filtration layer. It is suggested from the experimental result that the batch method ordinarily applied will overestimate the buffer ability. For the application of the stabilized soil to embankment, the minimum thickness of the filtration layer to prevent the alkali migration was calculated from the proposed parametric analysis, and the importance of permeability and workability of the materials as well as the neutralization ability were emphasized.
  • 坂井 宏行, 垂水 尚志
    1998 年 47 巻 2 号 p. 116-119
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    There are various methods available for determination of inorganic contaminants existing in ground, but none of them satisfies the requirements, namely, rapidity, inexpensiveness and high performance of analysis, from a standpoint of environmental geotechnics. Analytical methods are primarily required to be simple in treatment, but an analytical instrumentation developed recently needs a skill in operating them and strict maintenance control, resulting in an increased instrumentation and running cost of analysis.
    A novel analytical method for determination of inorganic ions contained in contaminated soil has been developed. Chemiluminescence (CL) emerges when a chemical species receives activation energy in a chemical reaction system and then the activated species reacts with other substances or alternate stable species. Thus a great difference between fluorescence (FL) and CL is observed in the transition process from the ground state to an excited state. However, the reversed transition process from the excited state to the ground state is the same for both FL and CL. Luminol is known as the most famous and popular synthetic reagent to generate CL, because it has a large quantum yield. The intensity of luminol oxidation CL is increased by a catalyst like heavy metal as added to the system, and the degree of the enhanced intensity is proportional to the concentration of the catalyst. Inorganic ions able to catalyze the luminol CL reaction can therefore be determined by the CL detection.
    The CL analysis using luminol as a CL reagent has many merits for determination of inorganic ions. A wide working range, high sensitivity, low detection limits, rapid analysis, easy operation and low cost are the features characterizing the method. The method was applied to detect contaminants accompanying the stabilization of ground samples. As a result, inorganic anions like silicate which is difficult to determine by other present methods could be determined easily. The chemical principle and analytical utility of this method, especially for anions, are presented.
  • 寺田 邦雄
    1998 年 47 巻 2 号 p. 120-123
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    In general, the effect of shallow soil stabilization is examined by the unconfined compressive strength of soil mixed with stabilizer in laboratory. Therefore, the in-situ strength of ground stabilized has not been conformed to be satisfied the criteria. In this paper, the author proposes a new evaluating method of shallow soil stabilization, i.e. the impact value of repulsion power of rammer fell down. The relation between the impact value and K value was examined for it, and it was found that the impact value was proportional to K-value. The author applied the impact value and the K-value to a quality control of ground in a factory. The other items used for the quality control are the unconfined compressive strength and a color identification test by phenolphthalein.
  • 江阪 匡示, 有岡 正樹, 森 邦夫, 後藤 徳善
    1998 年 47 巻 2 号 p. 124-127
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    Recent expansion of construction work has produced a large quantity of soil with high water content. The liquefied soil stabilization method by mixing solidifier (cement) and water with soil enables uniform back-filling for recovery or restoration of ground space. ReSM (Re-produced Soil Material) is a unique and simple method for high liquefied soil stabilization by using a specially modified concrete mixing truck. This paper presents the properties of stabilized soil by ReSM and the effective manner of management for the site application.
  • 澤 孝平, 友久 誠司, 雀部 和男, 厚東 敦志, 鈴木 一幸
    1998 年 47 巻 2 号 p. 128-131
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    For shallow soil improvement, the hardening agents are mostly used in powder. Some kinds of powder fly up in air and are carried by wind at construction sites, and they are called dust. Recently, the flying dust has become a serious problem at the sites near residential area and for workers' health.
    The purpose of this study is to investigate a practical application of dustless hardening agents that contain a small amount of oil. The authors examine the amount of dust from the agents, the strength of treated soil and the amount of oil which dissolves from the soil. Furthermore, they research the reason that the dustless hardening agent has been used in relation to environmental improvement.
    As a result, it has been found that the new dustless hardening agent is very effective in decreasing the amount of dust produced and in increasing the strength of treated soil. And the amount of oil which dissolves from the treated soil is extremely small in comparison with the specification limit of the environmental standard. Therefore, the new dustless agent can be applied increasingly in various fields.
  • 武田 一夫, 岡村 昭彦, 中澤 重一
    1998 年 47 巻 2 号 p. 132-135
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    Following a comprehensive field investigation on the effectiveness of slope protection techniques in cold regions, it was found that conventional protective grids usually cease to function within a few years because they protrude from the ground surface by repeated freeze and thaw cycles, and that such frost damages are significantly reduced on slopes covered by native dwarf bamboos (Sasa nipponica). Further, it was confirmed that the modified protective grids having a cross section shaped like “reverse T” are more effective in preventing frost damages than the conventional grids shaped like “I”. Based on these findings, an improved slope protection technique is recommended in which native dwarf bamboos are used as a ground cover protected by a new type of grids.
  • 福島 浩一, 佐内 康之, 川地 武
    1998 年 47 巻 2 号 p. 136-139
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    Although chemical grouting has been widely used as a simple and useful ground improvement method, it has a difficulty in drilling to fix a grouting tube near or under the ground of structures. If the permeation of grout can be controled, the substructure of buildings and tanks can be improved substantially. So, an attention was paid to the ionic property of metal acrylate that had been developed as a durable grout, and its utility for electrophoresis was examined by attempting to control the permiation electrically.
  • 西田 一彦, 西形 達明
    1998 年 47 巻 2 号 p. 140-143
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    At present, the main method of design in soil nailing depends on the calculation of tensile force in reinforcement material. On the other hand, it has been considered that the bending resistance of reinforcement materials restrains the deformation of soil and leads to massing of the reinforced area. In this paper, model tests using iron ore for backfill material were conducted to investigate the effect of reinforcing force on the reduction of horizontal earth pressure. Furthermore, the soil arching theory was applied to investigate the interaction between the reinforcements and the surrounding soil.
  • 中村 昭, 山口 嘉一, 小林 正宏, 橋本 保, 長谷川 悦央
    1998 年 47 巻 2 号 p. 144-147
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    Surface-treated cement used for cement powder grouting method has excellent dispersibility and permeability in compressed air. However, the surface treatment with water-soluble resin may cause a delay in hydration of cement.In order to study the hardening characteristic of surface-treated cement, laboratory hardening tests with the disturbed decomposed granite samples and an excavation survey for decomposed granite after field injection tests have been conducted. Based on the results of these investigations, an appropriate curing method for the ground with cement powder grouting is proposed.
  • 森川 義人, 所 武彦, 高橋 則雄
    1998 年 47 巻 2 号 p. 148-151
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    To evaluate the effect of soil improvement by grouting, the test results using a specified type of soil such as standard sand or silica sand and specified chemicals have been conventionally used. However, it is uncertain whether or not the results of such evaluations can be applied to the actual sites. Moreover, the strength of the sand solidified by chemical grouting has only been qualitatively evaluated by its relative density and/or grain size.
    In this study, the cohesion of sand solidified by chemical grouting was precisely evaluated by a simple method using the hydraulic radius of sand and the tensile strength of pure grout. From the result, a quantitative method was proposed for predicting the cohesion of sand solidified by chemical grouting at the actual sites.
  • 上原 方成, 原 久夫, 内間 義次, 仲松 照隆
    1998 年 47 巻 2 号 p. 152-155
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    On the northern part of Okinawa Island, the subtropical lateritic soil, so-call “Kunigami Maaji Soils (Reddish Soils)” develops widely on the terraces and terrain. As those soils are the natural residual soil of older metamorphic rocks and the younger gravelly soil of diluvial deposits, the land reclamation and public works cause the soil erosion and flow-out into the sea due to rainfall and also natural environmental problems. The field observation and investigative study of the slope erosion have been carried out to control and prevent the flow-out of reddish soils. The present paper deals with the experimental results of soil stabilization using the cementing material in the laboratory and on the site. The representative reddish soils were sampled and tested for the stabilizing effect on each soil. Also the field experimental study of the artificial slope stabilization under natural weathering condition during one year had been executed. The test results show that soil stabilization with the cementing material is quite effective to protect the soil erosion and improve the stability, consequently to prevent the contamination of river and sea.
  • 諏訪 靖二, 福田 光治, 濱田 晃之
    1998 年 47 巻 2 号 p. 156-159
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    In this paper, two aspects of the investigation into the liquefaction behaviour that occurred in the reclaimed lands by the Hyogo-Nanbu earthquake are discussed. Firstly, the conventional simplified method of predicting liquefaction based upon a grain size distribution curve has been proven to lead to a discrepancy between theory and practise. Therefore, by considering the representative diameter of grain size from the distribution curve as the basis, a predicting method in proposed to get the result harmonizing with other engineering properties. Regarding the second aspect, in some zones where liquefaction occurred, it was found that such measures as sand compaction, sand drain, packed drain, and rod compaction were also to be considered for improvement. Therefore, using the effective stress dynamic analysis, it is proposed that a critical strength level exists for protecting or reducing the degree of damage cauesd by liquefaction due to strong earthquakes.
  • 阿部 安秀, 中川 建治, 岡 千裕
    1998 年 47 巻 2 号 p. 161-168
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    In this paper, a stress function is obtained for a problem of infinite isotropic plate containing a central straight crack subjected to normal uniform load. This function is composed of a finite stress concentration and a process zone at the tip of the crack. The validity of the function is obtained through numerical calculation and the limit of its application to a finite plate is considered. By applying this stress function to the data of fracture development obtained by experiment, an evaluation of the length of the process zone was made, which up to now has been uncertain in this type analysis.
    The results support a conclusion that an analysis using this stress function is effective in evaluating the propagation of crack and the length of process zone.
  • 田中 學
    1998 年 47 巻 2 号 p. 169-176
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    A theoretical analysis of crack morphology based on the fractal geometry was made to derive an equation correlating the fractal dimension of crack, D" (the fractal dimension of crack profile in the two dimensional plane, 1<D"<2) with the fracture toughness, KIC. The fracture toughness, KIC, can be expressed as a following function of D": lnKIC=1/2{ln[2ΓE/(1-v2)]-(D"-1)lnrL}, where Γ is the work done in creating a unit crack surface, E is Young's modulus, v is Poisson's ratio, and rL is rmin/rmax, the ratio of the lower limit, rmin, to the upper limit, rmax, of the scale length, r, between which the crack exhibits a fractal nature (rminrrmax). The relationship between the indentation fracture toughness, and the fractal dimension of crack was then examined on various specimens of oxide, carbide and nitride ceramics and a hard metal.
  • 黄 〓煥, 田川 哲哉, 平 博仁, 宮田 隆司
    1998 年 47 巻 2 号 p. 177-183
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    Ductile fracture process in a titanium alloy composite reinforced with whisker-like TiB particles was investigated with particular reference to the effect of stress triaxiality. The materials investigated are TiB/Ti-8Al-0.5Mo-0.5V composite produced by vacuum arc remelting process and Ti-6Al-4V alloy for comparison. The in-situ reaction process provided strong interface between the matrix and TiB particles. TiB particles of 8% volume fraction raised significantly elastic modulus and tensile strength, while ductility was reduced. Degradation in ductility due to the stress triaxiality was more significant in TiB/Ti-8Al-0.5Mo-0.5V composite than Ti-6Al-4V alloy. Micro-voids in the composite were nucleated from the cracking of TiB particles at or beyond the plastic yielding of matrix irrespective of the state of stress triaxiality. They grew abruptly under a high stress triaxiality in the notched specimens. Fractographic observation demonstrated well the effect of stress triaxiality on micro-void coalescence type-ductile fracture.
  • 大野 信忠, 河邊 浩和, 三宅 卓志, 水野 衛
    1998 年 47 巻 2 号 p. 184-191
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    This paper describes a relaxation model of interfacial shear stress acting on broken fibers in unidirectional metal matrix composites reinforced with long brittle fibers. A cylindrical cell with a broken fiber embedded in power law creeping matrix is considered, and the broken fiber is assumed to have a bilinear distribution of axial stress. Then, on the basis of energy balance in the cell, a relaxation equation of interfacial shear stress is derived in a simple form. Under overall constant strain the relaxation equation is integrated to give an analytical solution, which is shown to agree fairly well with the numerical analysis of Du and McMeeking. Moreover, the relaxation equation is combined with Curtin's model, so that rupture time in long term creep is evaluated analytically on the assumption of global load sharing. It is shown that the resulting relation represents well the dependence of creep rupture time on applied stress observed experimentally on SCS-6/Beta21S at 500°C.
  • 安部 英昭, 山形 保男, 小澤 一雅, 森田 博
    1998 年 47 巻 2 号 p. 192-196
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    In order to develop a material for thermal striping in sodium, cold rolling materials with slits were manufactured, and thermal striping tests in sodium and stress analyses were conducted. Decrease of surface cracks was confirmed, because the stress was decreased by slits, and the materials strength was increased by cold rolling. The effect of stress decrease was evaluated by finite element method. By decreasing slit interval, the stress in the plane center and slit tip decreased to about 35% and 10%, respectively. The prospect of application of the materials to FBR was obtained.
  • 佐々木 敏彦, 林 政, 広瀬 幸雄
    1998 年 47 巻 2 号 p. 197-203
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    Applying an Eshelby's approach and wellknown Mori-Tanaka's theorem, the microscopic stress in a composite material which contains a finite concentration of inclusions was calculated from the elastic constants of the inclusion and matrix phases. The results were applied to derive basic equations useful for the method of X-ray stress measurement. Based on the theoretical results, some parameters which are important in the X-ray method were investigated, and their relations to the elastic constants of both the inclusion and the matrix were found. As a result, it became possible to calculate the X-ray elastic constants in a composite state (composite-XEC) from the elastic constants of single crystal of each phase. An example of numerical simulation was performed for the case of a SiC-particle-reinforced Al matrix composite material. An experiment was also made and the results were compared with the theoretical estimation.
  • 中佐 啓治郎, 加藤 昌彦, 張 東坤, 江河 史晃
    1998 年 47 巻 2 号 p. 204-207
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
    WC-Co cermet was coated on the smooth tensile specimens of annealed tool steel (JIS: SKD5) by high-velocity flame spraying. For some specimens, the pores in the coating were sealed by Zn-plating. After the specimens were immersed into tap water or 3% NaCl water, the tensile tests, where the load was applied parallel to the coating, were carried out in air to examine the change of interfacial energy by corrosive environments. With increasing tensile load, the coating is divided by several cracks and the interval of cracks is decreased by the repeating process of division, and the delamination of coating occurs after the crack division has finished. The interfacial energy decreases with an increase in immersion time, and the degree of decrease is larger in the specimen immersed in 3% NaCl water than in tap water. The interfacial energy of the Zn-plated specimen is almost the same as the no-immersed specimen up to the immersion time of about 1000ks in 3% NaCl water, but it quickly decreases to reach the same value as the no-plated specimen when the immersion time exceeds 1500ks. The interfacial energy is almost inversely proportional to the crack interval.
  • 浅野 種正
    1998 年 47 巻 2 号 p. 208-214
    発行日: 1998/02/15
    公開日: 2009/06/03
    ジャーナル フリー
feedback
Top