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節杭を用いたプレボーリング工法は，現地の土砂をセメントミルクで混合撹拌して造成するソイルセメントと，その中に建て込んだ節杭（既製コンクリート杭）で構成される。本杭の地盤から決まる鉛直支持力については多くの載荷試験結果に基づく支持力推定式が提案されている。地盤から決まる鉛直支持力を発現させるためには，節杭とソイルセメントが一体となって挙動し，節杭およびソイルセメントに作用する荷重を地盤に確実に伝達しなければならない。そこで，本研究では根固め部に着目した節杭とソイルセメントの押抜き試験を行い，一体性を確保するために必要な性能（付着性能）の検討を実施した。その結果，側圧が作用する節杭は作用しないストレート杭に比べて押抜き荷重が4倍程度となり，節部がソイルセメントとの付着性能を増大させる効果があることが分かった。また，節杭の付着性能を節部支圧強度で評価すると，実杭で想定される側圧の範囲で，ソイルセメント一軸圧縮強さの2倍程度になることが分かった。, Pre-bored piling method using nodular pile (precast concrete pile) consists of pitching the nodular pile into soil cement formed by mixing and agitating cement slurry and soil. Formulae for estimating vertical bearing capacity determined from the ground around the pile have been proposed based on the results of many loading tests. For vertical bearing capacity to develop, the soil cement has to transmit the load acting on the nodular pile to the ground. In this study, load test of nodular pile and soil cement in base bulb was carried out to clarify the adhesion effect. From the examinational results, the peak load of nodular pile was 4 times larger than the peak load of straight pile; it was found out that adhesion of nodular pile and soil cement is large effect. It was found out that the bearing pressure of nodular was 2 times larger than the unconfined compression strength of soil cement.

Este libro emana de la Conferencia Internacional "Agua, Megaciudades y Cambio Global", celebrada en París en diciembre de 2015 en ocasión de la COP21 y contiene los resúmenes de monografías de 15 megaciudades: Beijing, Buenos Aires, Chicago, Ciudad Ho Chi Minh, Estambul, Lagos, Londres, Los Ángeles, Manila, México, Mumbai, Nueva York, París, Seúl y Tokio.

Ce livre, issu de la conférence internationale « Eau, mégapoles et changement global », est le résultat d’un travail collectif de 33 auteurs et co-auteurs et contient les résumés de monographies de 15 mégapoles emblématiques - Beijing, Buenos Aires, Chicago, Ho Chi Minh Ville, Istanbul, Lagos, London, Los Angeles, Manille, Mexico, Mumbai, New York, Paris, Séoul et Tokyo. Cet ouvrage offre des informations précieuses et uniques concernant la gestion de l’eau dans ces 15 mégapoles.

This book is the outcome of the International Conference ‘Water, Megacities and Global Change’, and represents the collective work of 33 authors and co-authors. It contains summaries of monographs on 15 emblematic megacities: Beijing, Buenos Aires, Chicago, Ho Chi Minh City, Istanbul, Lagos, London, Los Angeles, Manila, Mexico, Mumbai, New York, Paris, Seoul and Tokyo. This edition provides unique information about water management in these megacities.

Pre-bored piling method using nodular pile (precast concrete pile) consists of pitching the nodular pile into soil cement formed by mixing and agitating cement slurry and soil. Formulae for estimating vertical bearing capacity determined from the ground around the pile have been proposed based on the results of many loading tests. For vertical bearing capacity to develop, the soil cement has to transmit the load acting on the nodular pile to the ground. In this study, load test of nodular pile and soil cement in base bulb was carried out to clarify the adhesion effect. From the examinational results, the peak load of nodular pile was 4 times larger than the peak load of straight pile; it was found out that adhesion of nodular pile and soil cement is large effect. It was found out that the bearing pressure of nodular was 2 times larger than the unconfined compression strength of soil cement.

The rheological properties of a clay-water system have been studied experimentally andtheoretically. The obtained principal results are as follows: The phenomenon of shear stressovershoot was observed at the initiation of a steady flow in a cone-plate rheometer. The intensityof the shear stress overshoot has a maximuns at a certain water content between the liquidity limitand the limit of a Newtonian flow.Moreover, based upon the rate-dependent relaxation spectra determined from the stressrelaxation tests after the stoppage of a steady flow, the validity of a theory of the nonlinear viscoelas-ticity is examined.

The rheological properties of a clay-water system have been studied experimentally andtheoretically. The obtained principal results are as follows: The phenomenon of shear stressovershoot was observed at the initiation of a steady flow in a cone-plate rheometer. The intensityof the shear stress overshoot has a maximuns at a certain water content between the liquidity limitand the limit of a Newtonian flow.Moreover, based upon the rate-dependent relaxation spectra determined from the stressrelaxation tests after the stoppage of a steady flow, the validity of a theory of the nonlinear viscoelas-ticity is examined.