The pre-lining method was developped to stabilize the cutting face and decrease the surface settlement in the thin earth covered and uncohesive ground tunnel.
This method was applied to the KATSUTADAItu nnel project having the above condition. The results were as follows:
(1) Safe and satisfactory work was achieved because the groud surface settlement was controled under 40mm by the pre-lining.
(2) The speed of the pre-lining work was 5-6 hours a cycle, the average excavation speed including the pre-lining work was 1.6m/day.

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We have developed the pre-lining method (PASS method) that can make the thin lining of arch-shell shape on the face, stabilizing the face and decreasing the surface settlement before the excavation. We applied this method to a shallow tunnel in diluvial sandy layer.Ground surface settlement, steel surport stress and shotcrete stress were measured in order to evaluate the ground behavior. This paper presents the comparison between those field measurements and the numerical analysis.The results show that the ground behaves as elastic body by the pre-lining.

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Japan Railway Construction Public Corporation is now constructing Kitanarashino Station in Narashinodai Tunnel on the Toyo Transit Railway Line, a new railway line directly connecting to center of Tokyo.
For the construction of this tunnel and large underground station, CRD (Cross Diaphragm)- NATM is developed and adopted to minimize influences on road traffic and activities in and around the shopping mall. Because it is excavated in unsolidified sand stratum formed in the Diluvium and the earth covering is only about 10m.
As the result, the ground surface settlement could be restrained and minimized.

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首都圏の都市鉄道では，朝ラッシュ時に定常的な混雑が発生している．混雑緩和に対する一つの解決策として，時差通勤をした者に対して，抽選で賞金が当たる抽選型報奨金制度がある．本研究では，東京メトロ東西線利用者を対象として，オーダードロジットモデルを用いて抽選型報奨金制度を導入した場合の鉄道利用者行動モデルを構築し，当選金額および当選金額に対する感度分析を実施した．その結果，当選の期待値が100円の下で当選金額を28.9千円（当選確率0.33％）とした場合，定額型施策よりも時差通勤施策の参加者が増加する可能性が示され，混雑率は197.5％となり，現状の混雑率である199％から1.5％減少することが示された．当選金額を20万円（当選確率0.05％）と高額に設定すると，混雑率は196.9％まで減少し，定額型施策よりも0.6％低下した．

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The purpose of this paper is to make clear the aspects of urbanization and greenery conservation policy, especially the woodland preservation project by the greenery conservation ordinance of the Yachiyo municipal government, and the landowners, response to the situation in Yachiyo City situated in Tokyo's suburban area, Chiba prefecture. The results obtained are summarized as follows.
Urbanization front has already passed through Yachiyo City and its population growth has been settled, but a great deal of greenery has been lost mainly because of the development of residential districts. Yachiyo municipal government, which is putting emphasis on the improvement of living environment, established “The Ordinance of the Greenery Conservation of Yachiyo City;” in 1975, which attempts to preserve these remaining private woodlands in the built-up area. Now, 15.6 percent (57 sites, about 24. 1 hectares) of the total woodlands which remain in the urbanization promotion area within the city planning district, has been designated as “Environmental Conservation Woodland” by the ordinance. To these designated woodland owners, the government pays for the maintenance expenses. But the municipal property tax and the urban planning tax of these areas have been rising, due to the increasing land value. In order to overcome these difficulties, almost all woodland owners (farmers) hope to cancel these designated contracts and to change it either to farmland whose tax is much lower or to a parking area which can earn cash income.
In order to preserve the remaining woodlands in the built-up area positively for the future, the municipal government either has to purchase these lands or has to put more strict restrictions on the land use by applying the “Urban Open Space Conservation Law” enforced in 1974, or some other people have to purchase these lands by the institution of “National Trust”. In any case, in the present situation, it seems almost impossible for the budget of the municipality to purchase these expensive woodlands.

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