「地震」と「震災」はそれぞれ別の対象を指している。「地震」は地面の揺れという自然現象を指す。それに対して, 「地震による災害」である「震災」は, 自然と人間生活の相互作用現象を指示している。それゆえ, 「震災」の研究には, 人間生活の様態を知ることが不可欠である。
このような視点に立つわれわれは, 本稿で, を事例として, 「阪神・淡路大震災」の特徴の1つである, 被害の区域差の記述を試みる。特に, 人的被害の区域差と被災者住民の生活・居住環境を記述する。
われわれは, を5区域に分け, それぞれの震災被害, 生活・居住環境のデータを集計した。データから, 芦屋を構成する5区域は, 市が標榜する「国際文化住宅都市」のイメージに合致する程度がそれぞれ異なることが浮き彫りにされる。中間平坦区域は, 「邸宅地」指標の高い山麓区域と, 「新住宅地」指標の高い埋立区域を圧倒的に上回る被害を出した。つまり, 「住宅都市」イメージから最も距離のある中間平坦区域は生活居住環境の対地震抵抗力が弱く, 最大の被害を出したのではないかと考えられる。

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Many studies are being conducted on the 1995 Hanshin-Awaji Earthquake from the earth science and architectural technological aspects, but urban structure is an important intervening factor link-ing causes and damages of an urban earthquake. This note will give a few insights from this point of view.
The distribution of debris of collapsed structure clustered around (1) Suma-Nagata district, (2) Sanno-miya-Yamate district and (3) Nada-Higashinada district was analyzed; (1) and (3) are inner-city areas with many wooden houses, located 3 to 10 km from the central business district.
Some network analyses are further performed usig GIS in the district of cluster (3). The number of arcs within a given road distance shows a characteristic decay caused by the earthquake, but its pat-tern varies by the distance band given. The fractal dimension of road network effectively summa-rizes this information. Calculation of the fractal dimension extracts many points either restricted by transportation facilities or river lines, or enclosed by debris as “dead ends”.

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No descriptions have been made about the methods of manufacturing artificial soils in most of the reports concerning with them.
In the preceding tests with artificial soils, the authors noticed that the touch of them was changing while we mixed and stirred a mixture of sand, bentonite and oil in a vessel with hands and that kneading effects would occur in an artificial soil as well as in natural soils by machanical manipulations, We thought that in ordinary soil bin tests, it would be better to use artificial soils beyond their “saturation point of kneading effect”, that is to say, artificial soils should be kneaded to such an extent that no further effects occur. That was the aim of this study.
A certain strength of an artificial soil can be expressed in equation (1). Cone and plate penetration resistances were selected as Q. Temperature was controlled within 24±2°C. The kneading action given to the mixtures examined in this test covered broad ranges when compared with soil mixing action given in ordinary soil bin tests.
The following conclusions obtained by this small scale test, in which rather a simple soil preparation method was adopted, suggest the necessity of reinvestigation in the preparation processes in usual soil bin tests at the use of artificial soils
1) Three kinds artificial soils were manufactured consisting of mould sand, bentonite and cylinder oil 90W. At first, equal quantities of sand and bentonite were mixed in the stirring vessel and after a minute, oil was added, namely, soil A; 9.91%, soil B; 16.12% and soil C; 20.00% in weight ratio. The grades of kneading time were determined by the observation of the test materials while they were being kneaded and are shown in Table 1.
2) Kneading effects and saturation points were recognized in two kinds of the test artificial soils (Figure g), Penetration resistances decreased (soil A) or increased (soil B) as the soils were kneaded and reached a constant value respectively within about 20 minutes, But, a steady tendency was not obtained in soil C.
3) A reproducibility of the artificial soil was examined (Table 2), The reproducibility at the surface layer was inferior to those of deeper zones. Though the numbers of repetition of tests were small, we dare to make a statement that in a similitude studies or studies on dynamic behaviours of soil machine system dealing with several percentages of differences of forces, elaborate soil preparing techniques will be necessary before tests. The problems concerning with soil preparation remain particularly in soil C as well as in natural cohesive soils.
4) Sufficient strength was found in the artificial soils to simulate natural soils covering from sandy barns to cohesive clay concerning with cone index.

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