著者

平野 昌繁 諏訪 浩 石井 孝行 藤田 崇 後町 幸雄

出版者

京都大学防災研究所

雑誌

京都大学防災研究所年報. B = Disaster Prevention Research Institute Annuals. B (ISSN:0386412X)

巻号頁・発行日

vol.27, no.B-1, pp.369-386, 1984-04-01

著者

平野 昌繁

出版者

The Association of Japanese Geographers

雑誌

地理学評論 (ISSN:00167444)

巻号頁・発行日

vol.39, no.5, pp.324-336, 1966-05-01 (Released:2008-12-24)

参考文献数

8

被引用文献数

7 4

---

A mathematical model of slope development is summarized by the relation _??_ where u: elevation, t: time, x: horrizontal distances, a: subdueing coefficient, b: recessional coefficient, c: denudational coefficient and f (x, t): arbitrary function of x and t, respectively. Effects of the coefficients are shown in figs. 1-(A), (B) and 2-(A). In order to explain the structural reliefs, the spatial distribution of the rock-strength against erosion owing to geologic structure and lithology is introduced into the equation by putting each coefficient equal a function, in the broadest sence, of x, t and u. Two simple examples of this case are shown in fig. 5. The effects of tectonic movements, for instance of faulting, are also introduced by the function f (x, t), which is, for many cases, considered to be separable into X (x) and T (t), where X (x) and T (t) are functions of x only and t only, respectively. An attempt to classify the types of T (t) has been made. Generally speaking, provided the coefficients a, b and c are independent of u, the equation is linear and canbe solved easily. With suitable evaluation of the coefficients (as shown, for example, in fig. 4-(A)), this linear model can be used to supply a series of illustrations of humid cycle of erosion, especially of the cycle started from faulting.

著者

平野 昌繁 諏訪 浩 石井 孝行 藤田 崇 奥田 節夫

出版者

京都大学防災研究所

雑誌

京都大学防災研究所年報. B = Disaster Prevention Research Institute Annuals. B (ISSN:0386412X)

巻号頁・発行日

vol.30, no.B-1, pp.391-408, 1987-04-01

著者

西部 均 平野 昌繁

出版者

The Association of Japanese Geographers

雑誌

地理学評論 (ISSN:13479555)

巻号頁・発行日

vol.75, no.7, pp.479-491, 2002-06-01 (Released:2008-12-25)

参考文献数

39

---

兵庫県南部地震による市街地被害の数量的評価のため,神戸市兵庫区・中央区の応急修正版住宅地図に基づいて震災被害率を計算した.家屋の被害には1950年の建築基準法施行が最も大きく影響していると考え,米軍空中写真を利用して市街地の戦災状況を判別し,震災被害と戦災状況を比較した.その結果,震災被害率は戦災の程度が大きいほど小さくなる関係にあることが確認された.その関係性を踏まえた上で,さらに1万分の1地形図を利用して震災被害率の空間分布の方位特性を分析した.その結果,戦災を免れた地区ばかりでなく,活断層に沿う部分でも被害が大きいことも判明した.このように空間的に市街地被害を評価することで,被害分布図のみでは判定しがたい家屋特性と活断層という被害要因の相乗効果を明確化することが可能となった.

著者

平野 昌繁

出版者

人文地理学会

雑誌

人文地理 (ISSN:00187216)

巻号頁・発行日

vol.35, no.5, pp.454-464, 1983

---

The variation principle is a concept for investigating the spatial pattern of any path on a given curved surface. From this point of view, properties of the Mt. Fuji climbing route are discussed, based on morphometric data. The route goes straight towards the summit on the gentle slope at the foot of the mountain, and shows a zigzag pattern on the steep slope near the summit.The variation principle maintains that the route can be a stationary one which minimizes some quantity. The straight portion of the route near the foot is the geodesic on a conical mountain, which gives the shortest distance to the summit. In order to explain the zigzag pattern near the summit, however, the amount of energy required to climb the mountain has to be taken into account. From this point of view, two types of models, namely, the excess energy model and the total energy model are possible, among which the latter seems better.If the latter model is employed, it is reasonable to assume that the energy required is proportional to the reciprocal of the power function of cosine of the slope. The exponent of the power function here is approximately 12. The zigzag route in this case has been designed so that the route needs 1.6 times as much energy as on a flat surface. The portion of the climbing route higher than 3200m in elevation is less steep, and this may correspond to the lower oxygen content above this level.

著者

平野 昌繁 諏訪 浩 藤田 崇 奥西 一夫 石井 孝行

出版者

京都大学防災研究所

雑誌

京都大学防災研究所年報. B = Disaster Prevention Research Institute Annuals. B (ISSN:0386412X)

巻号頁・発行日

vol.33, no.B-1, pp.219-236, 1990-04-01

---

Toppled rock blocks from the steep cliff along the Echizen Coast, Fukui Prefecture, hit apart of the shelter (rock-shed) below, and 15 persons in a micro-bus just passing there were killedby the breakage of the shelter on July 16th, 1989. The rock falls foregoing the toppling at leastfor one hour were reported by two eye-witnesses who had watched the full-process of the rock wallcollapse. Their statements give cleary the mode of the collapse starting with the tilting (toppl-ing) of a part of the joint block composing the partly over-hanged sea cliff. The joint block tiltedabout 30 degrees was then disintegrated, falling vertically on the earth surface. Distribution ofthe scattered blocks after the fall suggests the rotation of the blocks around an inclined axis atthe base of the cliff. The rotation is also confirmed by the fabric analysis of the distributed blocks.A part of the disintegrated blocks hit the rock-shed roof at its edge. Intensity of the impactforce given to the soil-covered roof is estimated to be 1100 ton-force, assuming the volume andsize of the individual block deduced from the survey after the fall.

著者

平野 昌繁 島津 俊之 野尻 亘 奥田 節夫

出版者

The Human Geographical Society of Japan

雑誌

人文地理 (ISSN:00187216)

巻号頁・発行日

vol.43, no.5, pp.493-503, 1991-10-28 (Released:2009-04-28)

参考文献数

21

---

A large number of gigantic landslides were triggered by typhoon rain in 1889 over the Totsukawa area, Nara prefecture, resulting a serious hazard. Their localities are identified exactly based on the Koaza name in the historical record, the Yoshinogun-Suisaishi. The identification of landslide localities over South- and East-Totsukawa areas was tried this time, and the results were summarized.Landslide larger than 4×104m2 in area have been shown by cliff marks on the topographic map in 1911 (Meiji-44) as same as in the case of West-Totsukawa area reported before. Topograhic features of gigantic landslides are still recongnized clearly on the aerial photos in 1953 taken even 65 years after the hazard.Description of the localities by Koaza name is frequent at the portions near the settlements or along the trafic routes at that day. In addition, some exaggeration in total number of large landslides is detected, if compared with the number of criff marks in the topographic maps in, 1911, even taking into account of the difference in threshold magnitude for description. Despite these biassed nature, it is clearly true that the Yoshinogun-Suisaishi surves the extraordinarily detailed record of the landslide localities, and this has come from the timing that the hazard occurred just after the detailed survey and registration of land-owner relationship there.

著者

平野 昌繁

出版者

公益社団法人 日本地理学会

雑誌

地理学評論 (ISSN:00167444)

巻号頁・発行日

vol.39, no.5, pp.324-336, 1966

被引用文献数

8 4

---

A mathematical model of slope development is summarized by the relation<br> _??_<br> where <i>u</i>: elevation, <i>t</i>: time, <i>x</i>: horrizontal distances, <i>a</i>: subdueing coefficient, <i>b</i>: recessional coefficient, <i>c</i>: denudational coefficient and <i>f</i> (<i>x</i>, <i>t</i>): arbitrary function of <i>x</i> and <i>t</i>, respectively. Effects of the coefficients are shown in figs. 1-(A), (B) and 2-(A).<br> In order to explain the structural reliefs, the spatial distribution of the rock-strength against erosion owing to geologic structure and lithology is introduced into the equation by putting each coefficient equal a function, in the broadest sence, of <i>x</i>, <i>t</i> and <i>u.</i> Two simple examples of this case are shown in fig. 5.<br> The effects of tectonic movements, for instance of faulting, are also introduced by the function <i>f</i> (<i>x</i>, <i>t</i>), which is, for many cases, considered to be separable into <i>X</i> (<i>x</i>) and <i>T</i> (<i>t</i>), where <i>X</i> (<i>x</i>) and <i>T</i> (<i>t</i>) are functions of <i>x</i> only and <i>t</i> only, respectively. An attempt to classify the types of <i>T</i> (<i>t</i>) has been made.<br> Generally speaking, provided the coefficients <i>a</i>, <i>b</i> and <i>c</i> are independent of <i>u</i>, the equation is linear and canbe solved easily. With suitable evaluation of the coefficients (as shown, for example, in fig. 4-(A)), this linear model can be used to supply a series of illustrations of humid cycle of erosion, especially of the cycle started from faulting.

著者

平野 昌繁

出版者

公益社団法人 日本地理学会

雑誌

地理学評論 (ISSN:00167444)

巻号頁・発行日

vol.39, no.9, pp.606-617, 1966

被引用文献数

1

---

斜面発達とくに断層崖発達に関する数学的モデルを論じた時には,斜面発達の数学的モデル化の大綱をのべるにとどまったから,ここでは数学的モデルにおける侵蝕係数の比,有限山体のモデル化,特別な境界条件の例,先行性河谷の例,斜面形の分類などについて, 2次元化された抽象的な斜面としてとりあつかう.この立場では,斜面は対称斜面と非対称斜面に2分され,後者はさらに凸型斜面と凹型斜面,不規則斜面に細分される.これらは何れも衝撃的隆起のあとにあらわれる斜面形であるが,そうでない場合にはことなった斜面形があらわれる.

著者

平野 昌繁

出版者

The Association of Japanese Geographers

雑誌

地理学評論 (ISSN:00167444)

巻号頁・発行日

vol.45, no.10, pp.703-715, 1972

被引用文献数

1 5

---

従順化係数と後退係数をもつ斜面発達モデルは係数の物理的意義を考えた場合にも不自然でない.これにもとづけば,平衡形は内営力と侵蝕力がバランスして生じる時間に依存しない形態として理解される.下刻作用に伴われる平衡形の生成や,その消滅過程についても同様にして検討が可能である.木曾川の先行谷を例にとり平衡形の性質を用いて係数を定めたところ,後退係数はmm/yearのオーダーとなった.

著者

柏谷 健二 平野 昌繁 横山 康二 奥田 節夫

出版者

公益社団法人地盤工学会

雑誌

土質工学会論文報告集 (ISSN:03851621)

巻号頁・発行日

vol.18, no.1, 1978-03-15

---

昭和50年8月16,17日にわたる台風5号の豪雨による高知県下の山腹崩壊の資料を用いて, 崩壊地の分布と崩壊に関係する諸因子, たとえば, i)降水量, ii)地形的特徴, iii)地質的特徴, などの比較検討を行ない, 傾斜と降水量を考慮した崩壊予測式を作っている。崩壊地分布は, 災害直後の空中写真および現地調査で, 降雨量は32か所の雨量観測所のデータで, 傾斜は2万5千分の1の地形図を用い2km×2kmの方眼内の平均傾斜角をホートン法で求めている。その結果, 次のことが明らかにされている。(1)継続雨量が一定のとき, 崩壊数はある限界傾斜角まではコウ配に比例する。(2)傾斜が一様なとき, 崩壊数は日雨量から崩壊無効雨量を減じたものに比例する。(3)崩壊予測の一般式としては次式が推定できる。N(i, r)=k_<ir>・(i-i_0)^p(r-r_0)^q ただし, i=tanα ここで, N(i, r) : 単位面積当たり崩壊数, k_<ir> : 係数, i_0 : 限界傾斜角の正接, r : 継続雨量(mm), r_0 : 崩壊無効雨量(mm), α : 単位地域内の平均傾斜角