躍進を続けるわが国プラスチック工業の中で, FRP(fiber glass reinforced plastics,強化プラスチック)は住宅設備などの面で独自の発展を遂げつつある.現在,FRP製品の約50%はいわゆるハンドなどの手作業により製造されており,残る50%が,連続積層成形,プレス成形など,機械装置を用いて生産されている.filament windingは装置によるFRP成形法の一つである.この製品はFRPの中でも特に性能のすぐれたもので,従来は,ロケット,航空機部品など力学的性能が重視される用途に使われていた.しかし最近では,その生産性がすぐれているところから,一般のタンクや配管用パイプに相当に進出するきざしが見え始めている.

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　GFRPの疲労照査では構造部材レベルの検討が望ましいが，材料疲労試験と比べて部材疲労試験は実施例が限られている．そこで本研究では，材料疲労試験から，GFRP部材の疲労損傷や部材剛性をFEM解析上で評価する手法を提案した．提案手法では，実験により疲労損傷を生じたGFRPの剛性低下に着目し，材料疲労試験から構築した剛性低下モデルをシェル要素に実装した．まず，実験と単要素モデルを用いたFEM解析の比較から，提案手法の妥当性を確認した．さらに，GFRP-コンクリート複合桁の曲げ疲労試験を解析上で再現した．その結果，設計荷重下では繰り返し載荷後も疲労損傷が発生しないことを確認した．また，載荷荷重や位置を変化させた解析を行い，GFRP中空部材では上フランジ下面の引張疲労損傷が先行することを明らかにした．

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GRPのハンド法について, 成形作業者の技能の評価基準を検討した。
熟練者 (A₁) と未経験者 (A₂) の成形した試験板を引張りおよび曲げ特性で比較した結果, 技能の評価は, これらのデータの大きさによっては決められず, 設計厚さの達成度と厚さ, ガラス含量, 空洞率および力学的性質の標準偏差で決めるべきであることがわかった。
さらにこの技能を, 成形温度15, 23および30℃で検討したが, 厚さの設計値からの偏差は, A₁よりA₂のほうが大きく, 標準偏差もA1よりA2のほうが大きかった。
ガラス補強材の成形中における流れは, 低温時よりも高温時のほうが大きかった。
室温, 水中浸漬, 加熱など4種の硬化条件を力学的性質によって比較した。

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Hand lay-up molding method is the simple molding method which alternates between setting mat and impregnation. This method is able to mold complex shapes with low-costs. However, this method is performed all processes by human hands so that defects of voids and resin ununiformly are easy to happen. A lot of tacit knowledge such as sensory elements exists on the work with human hands. These disadvantages are able to solve by achieving robotization. Formalization of tacit knowledge on the expert is necessary to develop the robot with high-quality molding technology. The moldings and processes analysis with different skill level workers were investigated. In this study, molding conditions were three worktable angles to simulate actual products. The different of molding time with expert and non-expert was found. Non-expert took 1.9 to 2.9 times. It can be noted that the molding time of non-expert longer than expert. Especially, non-expert affected the molding time due to large numbers of handling the roller in the impregnation and finalization processes. Thickness coefficient of variation of non-expert at worktable angles 90 degrees was twice larger than expert. The percent different of bending strength between expert and non-expert was about 5.0%. It can be noticed that the bending strength of expert higher than non-expert. Worktable angles such as 45 degrees and 90 degrees were required more skills and experiences.

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Many player tend to think that their left side of ability in lay-up clean shooting are inferior to those of right side. In this respect, it is interesting to know how high they want to have as their ideal motor abilities, and the difference in them between left and right side. To clearly the difference between right hand shot and left hand shot, four males were employed as the subject, and lay-up clean shot was taken photograph 5 times for each hand shot. Left hand was not inferior in physical fitness in so far as it was independent of awkwardness. For instance, muscle strength, general endurance, and agility performance was normal for the most part. But as they have no training term, consequently they can not move themselves accurately. Accordingly they are inferior in physical exercise need coordination. Four subject showed a little larger value in many factors in case of right hand shot. The lay-up clean ahooting, the average value of 5 trials on each hand, appeared to be different between right and left hand shot, therefore constant tendency among subjects and statistically significant difference between those two shots were obtained. All mean values calculated in each category are shown in Table 1, and Figure 1.

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　GFRP は重量比強度や耐久性に優れているが，損傷評価手法については不明な点が残されている．特に，疲労損傷として発生する樹脂内き裂や層間剝離は非常に微細であり，外観目視から発見することは困難である．そこで，本研究では，静電容量を用いた疲労損傷評価手法を検討した．まず，電極をGFRP両面に接着した試験体の引張疲労試験を実施し，初期の疲労損傷である樹脂内き裂の発生は静電容量に影響しないことを明らかにした．次に，電極を内部に埋設したGFRPを製作し，引張疲労試験を通して，静電容量と繰返し数，残存剛性の関係を調べた．実験の結果，疲労寿命中期以降で層間剝離の進展に伴い静電容量が低下し，静電容量の低下をもって疲労損傷を評価する可能性が示された．一方，実験を通して電極自体の耐久性も確保する必要性が明らかになった．

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　教員が想定していない観点からの受講生の授業の評価を知ることは、授業の質の向上改善に繋がると考えられる。そこで、本研究は、バスケットボールの授業に対する感想文にテキストマイニングを用いて受講生が受けた授業に対する潜在化している評価の構造を明らかにする。大学および高等専門学校でバスケットボールの授業を受講した学生218名に対し、授業に対する評価を自由記述形式で回答する感想文の作成を依頼し、その文章中から名詞と動詞と形容詞を抽出した。まず、頻度分析の結果、「ショット」「練習」「試合」「ドリブル」「パス」等の名詞が多く、学生の評価の観点が攻撃の基本技能にあることが考えられた。さらに、コレスポンデンス分析およびクラスター分析を行い、品詞間の関連を分析した結果、「名詞×形容詞」では「楽しい」「上手い」など好意的な評価を示す形容詞に「バスケ部」「生徒」「戦術」などの名詞が、「きつい」「難しい」など否定的な評価を示す形容詞に「指導」「

」の名詞が近い位置を示し、授業中のバスケ部員への憧れや戦術を学習することが好意的に捉えられ、逆にシュートの練習につまずきがあったことが示唆された。

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　近年，高強度・耐食性・軽量といった特性を有するGFRPを主要構造材料とした歩道橋の事例が多数見受けられる．しかし，道路橋・鉄道橋については国内の事例はなく，今後はGFRPの耐食性・軽量性を活かして応用されることが期待される．道路橋・鉄道橋では，荷重・設計条件が歩道橋の場合とは異なるため鋼材と比べて弾性係数の小さいGFRPを主要構造材料として用いる場合，厚板が使用されることが予想される．また，板厚が数十mmに達するGFRPはこれまでに応用事例もほとんどなく，その成形精度・機械的特性の評価法についてもデータが不足している．そこで本論文では板厚が40mmのGFRPを成形し，その機械的性質の評価を行うことを通して，厚肉GFRPの適切な材料試験法について検証するとともに，設計のための基礎データを示す．

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This study presents basic data on temperature dependence of mechanical properties of GFRP materials. First, coupon specimens are collected from GFRP plates by hand lay-up molding. Then, material tests are conducted under different temperature environments to clarify the relationship between temperature and tensile properties. In order to receive repeated temperature histories in the actual environment, a tensile test was also performed on the cooled material after heating. As a result, it was found that the tensile performance of GFRP decreases as the temperature of the specimen increases. It was also found that the specimens that had undergone the cooling process after heating had the same tensile performance as the initial state.

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    The purpose of this case report was to describe and study the author's experience with teaching the dribble layup to a beginning basketball player, and to provide knowledge that would help other coaches teach the technique. The beginning female player had problems making a smooth transition from the dribble step to the shooting step during the catch phase of the dribble layup, and had difficulty making a stable throwing motion. Therefore, the author proposed a step-by-step practice drill to promote the connection of the two skills of dribbling and shooting, and attempted to create a movement of kicking with the axle foot at the beginning of the shooting step and develop a rhythm when catching from dribbling. Based on the practice drill, the learner shouted “un” for the final dribble and “1, 2” for the shooting step, and got the hang of the movement of entering the step and timing it together with the shouts. The findings of this study highlight the importance of placing the point of awareness on the technique before the catch phase in order to make the connection between the dribble and the shooting step smooth. Knowledge gained from this report will be helpful to other coaches teaching beginners the dribble layup.

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In this study, the monitoring method using ultrasonic waves, which has been developed in our laboratory for RTM molding, were applied to hand layup molding, and the effect of the FRP molding method on the mechanical properties of the molded products was evaluated. From the results of resin impregnation monitoring, it is confirmed that the reflected waves from the upper and lower interface of FRP layer could be detected not only in RTM molding but also in hand layup molding, indicating that ultrasonic resin impregnation monitoring is effective in hand layup molding as well. In addition, tensile tests of the molded plates with different molding methods showed that FRP molded by RTM method has lower mechanical properties than hand layup products.

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Basic problems on the design of fiberglass reinforced plastic (FRP) ship hull structures are considered. The design procedures of FRP structures are considerably different from the conventional method of metal structures.
FRP is a kind of composite materials and is inherently heterogeneous anisotropic, and the FRP structural design is closely connected with the FRP material design (in particular, the lamination design of FRP). Specially, compensation of law rigidities of FRP (one of the main faults of the material) is important in FRP structural design-composite constructions such as stiffened panels or sandwich panels.
In this report, rigidities of FRP laminated plates (using glass mat and roving cloth) are considered on the basis of classical theory of anisotropic laminates. Further, the large deflection of FRP laminates subjected to hydrostatic pressure is considered by means of approximate method of orthotropic membranes, when rigidities derived above are used.

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　近年，軽量性や耐食性に優れた材料であるFRPが注目を集めている．しかしFRP部材のボルト接合に関して，FRP材料が自由に材料設計が可能であることから，統一的な設計手法が確立されていないのが現状である．FRP材料が社会基盤施設の構造部材として普及していくために，FRP部材における接合部の強度を適切に評価し，設計手法が確立される必要がある．そこで本研究ではハンド成形されたGFRP部材のせん断支圧ボルト接合に着目し，接合部耐力と破壊形式の評価を目的として，寸法パラメータ，ボルト軸力の有無，添接板材料など接合条件の異なる単ボルト供試体を用いて強度実験を行った．その結果から，幅w/d≧2.5かつ縁端距離e/d≧4の時に支圧破壊が生じること，ボルト軸力の導入は接合部耐力を増加させることなどを明らかにした．

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Generally, Fiber Reinforced Plastics (FRP) have been regarded to have same mechanical properties if reinforcing fibers, reinforcement configurations, matrix resins, surface treatment and volume fraction of fibers are same regardless of molding method. However, it is considered that interface properties are changed by impregnating process among hand lay-up method and VaRTM method. In this study, effects of difference in molding method on mechanical properties and fatigue properties of FRP were investigated. As a result, static tensile properties, low-cycle fatigue properties and interlaminar fracture toughness were changed by molding process.

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