Spiral steel wires wound over adequate length near the end or the butted part of the members will produce gripping force, especially when they are under tension. The joint of the members where the spiral wire is thus applied is called“wire grip”. This has been used gradually for joining wire ropes or steel bars, but the transmission mechanism of its stress and gripping force has not been mechanically made clear.
In this report the theoretical analysis is made of how the tension acting on the member is transmitted to the wire grip under consideration of the contact pressure and the friction force between the members and the wire. The following results have been obtained by comparing its theoretical studies and experimental investigations.
(1) Under tension the wire grip is distributed among the three regions which show different mechanical behaviors. The theoretical results coincide with the experimental results on mechanical properties in each region. Hence this analytical method seems to be valid for resolving the transmission mechanism of the stress in the wire grip.
(2) The resistance load of the grip P_S for the sliding on the surface of the member depends sensitively on the coefficient of friction μ. In this experiment μ is 0.27 and generally it is considered to be μ=0.2∼0.3.
(3) The resistance load of the grip P_S increases rapidly with the larger length of the grip and beyond a certain length the member is broken before the sliding of grip on the surface of the member. The minimum requisite length of the grip L_S, in case which P_S equals to the breaking load of the member, can be theoretically calculated.
(4) The resistance load of the grip P_S becomes larger with the increase of the initial gripping rate φ.
(5) The optimum wire grip can be designed by this analytical method in connection with the pitch angle of spiral wire β, the diameter of wire d and the length of the grip L.

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The steel cord has been widely used as a reinforcing fiber of the radial tire belt structure which is a FRR composite laminate. In this study, the torsional stiffness of steel cords having single or double layers were analyzed and verified by experimental results. Two loading cases of the regular and the reverse torsions were treated separately. In the former case a contact condition among constituent filaments twisted together in a steel cord should be considered in the analysis, in contrast to the latter case. Then, we obtained explicit formulae for these two cases. They were approximated further for a small helix angle. The predicated results for a steel cord with a single layer showed excellent agreement with experimental results in both regular and reverse torsion cases. The torsional stiffness of the steel cord with double layers were obtained approximately by superimposing two stiffnesses of constituent single layers. The calculated results are also shown to coincide well with the respective experimental results.

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It is the aim of this paper to make analyses of torsional rigidity and the stress of a flexible shaft, and make comparisons between theoretical and experimental results. Experiments were conducted with a view to these ends, and the results obtained are summarized as follows:
(1) A flexible shaft, when its torsional properties is treated analytically, should not be considered as a group of coil springs, because the contact pressure arises in the side wires of any two layers.
(2) An analytical method established by considering the contact pressure between the two layers is useful to determine the torsional properties of flexible shaft.
(3) The torsional properties of a flexible shaft depend not so much on the construction of internal layers as on that of the outer layer.
(4) In the case of flexible shafts having a constant outside diameter, the torsional rigidity increases and the stresses of side wires decrease with the increase of the number of side wires in the outer layer.
(5) The torsional rigidity C and the stress of side wires σ of a flexible shaft can be approximately determined by applying the practical equation proposed by the authors in which the construction of side wires in the outer layer is mainly taken into consideration.

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臨床検査として最近導入された血清1,5AG(anhydroglucitol)につき臨床的意義を検討した. 外来通院糖尿病患者(慢性膵炎18例, NIDDM68例)を対象とし血清1,5AG, HbA₁, 空腹時血糖(FPG)を測定した. 膵性糖尿病インスリン治療例で1,5AGは低値を示し, 経口剤・その他による治療例との間に有意差があった. 一次性糖尿病ではHbA₁, FPG各々と1,5AGの間に有意相関がみられた. 両糖尿病とも1, 5AG, HbA₁, FPGの異常頻度は高率で, 治療によりそれぞれ10μg/ml, 10%, 100mg/dl近傍へ推移した. 測定値の分布は1,5AGが最大で, その上昇はHbA₁, FPGが正常化する時期に著明となり, 後二者が正常域にあっても1,5AG低値例がみられた. 以上より, 膵性糖尿病インスリン治療者で1,5AG低値例が多く, 1,5AG正常は血糖コントロール安定化を示唆するものと考えられる.

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FRRはFRPに比較して, 大きな変形を可能にする構造物の部材として用いられている. このためFRRで用いられているコード, 例えば, ナイロン, ポリエステル, アラミド, スチールなどは, 構造物の屈曲疲労特性の面からも撚りコードが一般に利用されている.
本論文では, 円柱ゴム中に撚りコードが埋め込まれたFRR柱の引張り弾性率についての研究を, 解析的および実験的に行った. 具体的には, まず第1に, ゴムの影響を無視した撚りコードのみの理論的解析を行い, 次に有限要素法を用いて撚りコードを有するFRR柱の解析を行った. 特に有限要素解析では, コードの撚りピッチおよびゴムの弾性率の影響について検討を行い, また, 実験値との比較, 検討も合わせて行った. その結果, 解析解, 有限要素法による計算結果および実験値との間にほぼ良い一致が得られた.

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The purpose of this paper is to demonstrate a new procedure for conducting membrane analogy experiment to analyze Saint-Venant torsional stresses. Using the procedure, two torsional bar section, square and twist drill section have been investigate and the results were compared with the ones obtained by numerical finite difference method.

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Flowing concrete was produced by adding some superplasticizers and their properties were examined experimentally. The results obtained are as follows.
(1) The most suitable sand percentage in flowing concrete can be approximately determined from the amount of slump.
(2) There is such trend that the flowing properties improve with increasing unit amount of cement. It is desirable that concrete contains more than 420kg/m³ of fine particles of less than 0.3mm size.
(3) The flowing property and slump loss of flowing concrete vary depending upon the temperature and timing of the addition of superplasticizers.
(4) The compressive strength develops up to three years in the same trend as in the case of low slump concrete.
(5) The relationship between compressive strength and tensile one or static modulus of elasticity is the same as that of conventional concrete.
(6) The drying shrinkage and the durability to freezing and thawing are the same as those of low slump concrete.
Also, several examples of job site application of the flowing concrete were given along with the mix proportion used and the reason of adopting the present method.

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HDTV (ハイビジョン) のスタジオ用VTRは, 画質, ダビング (複製) 性能の点からディジタル記録方式のものが期待されており, BTA規格によるハイビジョン信号を記録するディジタルVTRの仕様がNHKからガイドラインとして提案されている.今回, これに従って, 1.2Gb/sディジタルVTRを試作した.現在, 実用化されているディジタルVTRに比べ, 高速, 高密度記録のため, テープヘッド系における誤り率の確保が重要課題となる.このため, 次の検討を行った. (1) 代表的な信号検出方式の中から, 新たに開発したメタルテープ, 多層化SAFヘッドの周波数特性, 雑音周波数特性に適した方式を求め, 積分検出を採用した. (2) 積分検出の高域補償として5タップトランスバーサルフィルタを用い, 0.345μm/bitの短波長記録で発生する大きな符号間干渉を除去した. (3) シャトルモニタやスロー再生などの可変速再生に対処するため, タイミングクロック抽出用PLLのループ内にテープ走行速度情報を取込む構成とした.

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Experimental tests have been conducted on the mechanical behavior of a CFRP 1×7 strand cable with a central core subjected to torsional loading. The failure process of each helical string and the core has been probed independently by means of an electrical resistance method. Unloadingreloading torsion test has also been done to investigate the effects of cyclic loading. It has been found that the torsional failure of the CFRP strand cable has two stages. The first is a compressive failure of core, which does not immediately result in a loss of load-carrying capacity, but it later induces a tensile fracture of all spiral strings, i.e. the final failure of the cable. Although the tensile strength of the CFRP strand cable is almost the same as that of the steel strand cable of the same diameter, its torsional properties are far lower than those of the steel cable. Cyclic loading causes more damage to the core than to the spiral strings and it reduces the torsional strength significantly. The electrical resistance method, which requires no external sensor, works successfully for the sensitive detection of the fiber breakage in core and spiral strings and hence, the present CFRP strand cable can be regarded as a smart structural element with health-monitoring capability.

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