建設産業は他産業と比較して生産性が低い産業といわれている．また，近年の公共投資への過度なコスト縮減が建設産業の技術の進歩・継承を阻害する恐れがあるとの指摘もある．本研究の目的は，わが国の建設産業の技術が社会的背景によりどのように変化したのかを把握し，その問題を明らかにすることである．そこでマクロとミクロの視点から技術進歩の指標としてTFP（Total Factor Productivity；全要素生産性）を計測した．マクロ的視点においてはわが国の建設産業全体と他産業のTFPを比較した．また，ミクロ的視点においては，建設産業の個別企業別のTFPを計測し，各々の特徴を把握し，建設産業の問題を明らかにした．

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本研究は,「合成構造用鋼材」の一種である突起付き鋼板のせん断伝達特性を明らかにすることを目的に, 計84体の供試体に対し一定側圧の下での引抜きせん断載荷実験を行い, その破壊形式, 耐荷機構, せん断強度, ずれ変形特性ならびにスタッド併用時の挙動を調べたものである. 供試体は, 平鋼板, 縞鋼板, 線状突起付き鋼板の3種の鋼板を用い, 突起の高さ, 間隔, 個数, 側圧強度ならびにスタッドの有無を実験変数に選び, 得られた結果より各実験変数がせん断伝達特性に及ぼす影響を定量的に評価し,せん断伝達強度の算定式の提案を試みた. さらに, 突起付き鋼板とスタッドとの累加強度特性ならびにリブ鋼板の挙動に関する簡易数値モデルの構築についても検討を加えた.

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近年我が国の河川護岸で増加しつつある外来植物ヒメツルソバについて，大阪府堺市を流れる大和川水系西除川の護岸擁壁での生育位置と水位変動の関連を検討した。2015 年夏に，59.6m 区間の擁壁の写真撮影を行い，水平距離1m 間隔で設置した調査ライン上の株の垂直分布位置を画面上で記録した。2005 年から9 年間の水位変動記録との関連を調べた結果，ヒメツルソバは，年間累積冠水日数が260 日を超えると深刻な影響が表れ，300 日以上で生育が困難になること，また年間連続冠水日数が140 日を超えると深刻な影響が表れ，200 日以上で生育が困難になることが示唆された。また冠水以外に，擁壁の乾燥や本種の種子供給時期も生育位置に影響する可能性が考えられた。

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Primary purpose of this study is to practically optimize the process through which landscape design will contribute to restoring natural environment in riverside parks in urbanized areas. The following points are identified through the continuous survey and analysis of vegetation and related environment in "Natural Zone" of Ishikawa River Park in Osaka Prefecture for five years of period after 1st stage of park development was completed. A series of phenomena that will take place in and around the environment of the site would be integrated into the process of planning and design of landscape by focusing on differences found in their scale, frequency and endurance.For instance, artificial disturbance of vegetation such as maintenance practice of agricultural irrigation channels would be effective to promote nature restoration if it is taken into account of planning and design in advance.In addition, it would be possible to estimate post development changes and their future trends clearly, and to project the process of nature restoration as well, by planning and design based on scale of time-space in the landscape. All these findings suggest the potential that landscape design would be developed as a practical methodology for nature restoration with long-term practice that integrate design and maintenance of post construction periods.

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Primary purpose of this study is to practically optimize the process through which landscape design will contribute to restoring natural environment in riverbed land in urbanized areas. The following points are identified through the survey and analysis of flora and related environment in “Natural Zone” of Ishikawa River Park in Osaka Prefecture. Controlled flooding of extra agricultural water into riverbed land and maintenance activities of irrigation channels including excavation of sediment were incorporated as a vegetation control measure. The results of flora survey indicated that although stable communities of perennial species have been established in major riverbed land due mostly to dry condition, some induced disturbance of vegetation such as maintenance practice of irrigation channels would be an effective measure to reset the environmental conditions and promote diversity in species composition. It was also indicated that difference in function and maintenance practice of irrigation channel affects the extent and frequency of those artificial disturbance that turns to be a measure of vegetation control. On the other hand, since natural disturbance is not precisely predictable, it is necessary to carefully trace the post disturbance changes in flora and to reflect those on the process of planning and design of riverbed landscape.

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This study illustrates a process of citizen participation in planning, design and maintenance of Ishikawa River Park in Osaka Prefecture paying specific attention to consensus building among the participants and the administration. Core members of the citizen groups, most of them are from several sects that had opposed to the plan prepared by the administration, played an important role throughout the process. They worked as facilitators to enhance discussion and collaboration within local communities to reach the agreement for conservation of riparian landscape developed along the river. Based upon results of the case study at Ishikawa River Park, it is pointed out that the primary issues of citizen participation process are in attributes of participants and small groups of citizen are more eligible for promoting planning and design of the park, while new members with vitality and expertise are necessary to enhance efficiency in participation.

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