Heat balance analysis, on the assumption that the condition of the ground surface is uniform like in a flat area, cannot be made in a mountainous area. However, at the time of planning of land use, irrigation and drainage, it is necessary to consider the heat balance in mountainous areas. In this paper, from the standpoint of micrometeorology, the thermal and moisture environment at the top and in the valley of a mountainous area were investigated, and the qualitative analysis of heat balance at each location was made. As a result, the following facts became clear:
(1) A great difference between the values at the top and in the valley was comfirmed as regards air temperature, wet-bulb temperature, relative humidity, soil moisture, ground temperature and wind speed (Figs.3-7).
(2) In the daytime, the water vapor pressure at a height of 50 cm was higher than that at a height of 350cm, and that difference was larger in the valley. The air temperature at a height of 50 cm was higher than that at a height of 350cm, and that difference was larger at the top (Fig. 8).
(3) The latent heat flux was calculated using the heat balance method from the air temperature and the water vapor pressure at heights of 50cm, 150cm and 350cm. It might be difficult to estimate the latent heat flux using the heat balance method in a mountainous area, as the calculated values were unreliable during nighttime. But in the daytime, as the sun's altitude became higher, the continuity of the vertical flux was comfirmed (Fig. 11). At that time, Bowen's ratio was constant (Fig. 12).
(4) Heat balance in the daytime was calculated using the constant Bowen's ratio at the top and in the valley (Table 1).
(5) The moisture condition near the ground surface was estimated from the antecedent precipitation, soil moisture distribution, small pan evaporation and Penman's potential evapotranspiration (Tables 1, 2, Figs. 10, 13).
Immediately after a rainfall which is enough to moisten the ground surface uniformly, the heat balance at the top equals that in the valley. Successively, water moves from the top (divergent area) to the valley (convergent area) due to gravity force, and the top becomes dry, while the valley becomes wet. Accordingly, latent heat flux in the valley, and sensible heat flux at the top become important terms of heat expense. The heat balances in a mountainous area are illustrated in Fig. 14.

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The neutron scattering method has some obvious merits over other methods of measuring the soil water content in situ. In order to make the best use of the efficiency of a neutron moisture meter in the field, it is necessary to previously obtain reliable calibration curves for the neutron moisture meter. Soil water content in an actual sandy field is in the low moisture range, compared with the other soil conditions. Therefore, it is significant to know whether the linearity of the relation of the count ratio versus the volumetric water content on the calibration curves is valid, and to know whether the soil water content estimated by the calibration curves represents the soil water content in an actual sandy field.
In this paper, a method of making the calibration curves of a depth-type neutron moisture meter for dune-sand is described in detail. In order to compare the accuracy of the calibration curves for two different clearances, the standard error of estimate of each calibration curve was calculated. It was recognized that the smaller clearance between the probe and the access tube had a principal effect on the higher sensitivity of the calibration curves. The calibration curves for the depths of 15, 30, 45 and 60cm were determined only for the O.5mm clearance. The semi-theoretical calibration curve as a function of the soil water content and dry bulk density was described and compared with the calibration data. From the results of the field experiments, it was recognized that the calibration curves obtained from the dune-sand with a uniform soil moisture profile were successfully applied to measure the soil water content within 1% by volume in an actual sandy field for practical use.

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We examined water allocation for greenhouses in mixed dry fields. The results of our research concering water allocation are summarized in the following.
1) The quantity of water used is on the increase due to an increase in the amount of area used for greenhouses. For mixed dry fields, the amount of water used for greenhouses is the largest during the autumn season.
2) The water allocated for greenhouses for a one-day period during the summer months has its peak in the morning and the evening; but for the winter months, it is in the mulling only.
3) In dry fields, the peak usage of water is in the evening in the summer months and in the morning for the winter months for a one-day period.
4) For celery, the amount of irrigation water supplied is more than consumed in greenhouses. The amount of irrigation water used is moderate for melons, watermelons and green peas.
5) We estimated the change in the quantity of water use due to an increase in the amount of greenhouse area under cultivation. After concluding the above, we carried out research on the countermeasures.

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The survey on the water management has been carried out within a small area (7. 6 ha) which is irrigated by a small reservoir called “Osawa Shin-ike”. This area is included in the “Toban irrigation project” area, where three main dams and a considerable length of waterways are now being constructied in order to supply irrigation water.
The characteristics of water management in the area derived from the survey are as follows.
(1) Average release of the reservoir is 4.5mm deep each time throughout the irrigation period. Water is released every day except on rainy days from the start of irrigation to the end of August, and in September intermittent releases are carried out.
(2) Water level in the paddy fields are variable. The highest level is 7 cm, which is far under the crest of the drainage ditch. This fact shows there is no waste of water due to a spillover.
(3) Paddy fields are supplied with water usually by a rotation interval of two days, but the interval is changeable after “nakabosi” drainage because of difference in the demand of each field.
(4) A waterman supplies water to each field within two hours at a time.
(5) The supplied water quantity varies dependent on the differing water requirements, but the submerged duration in each field is kept constant.
(6) Upper and middle portion of the area is supplied with water of the “Shin-ike” release at 75% of total supply, and lower portion gets 20%. The weigh mean ratio of reused water is 45. 3% within the area.
(7) Average utilization rate of rainfall (utilized rainfall/supplied water) is about 8%.

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Most of the reclamation settlements have a planned network of roads. So there are very good examples in order to make clear some principles in road system.
The road network in a dispersed housing settlement, which lies in a reclaimed area, in the town of Nadasaki in Okayama Prefecture, is of the functional type to allow for the easy flow of transportation. The roads of this settlement could be classified into two parts: namely, ‘inner settlement roads’ and ‘settlement connecting roads’.
As a result of such a road system, the town government succeeded in constructing a functional road network which is very useful for people.
However, the roads in the settlement adjacent to the above were construct in the line type not using the fanctional approach. In the latter type road network, the town government was not able to incorporate the demands of the inhabitants in the making of the road system, and therefore, failed to make a reasonable road system.
Due to our observations and discussions, we have come to the conclusion that the town government should reconstruct roads based on the functional road system suitable for a settlement pattern.

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A rural road network is functionally different from ordinary roads. That which is of paramount importance in the construction of rural roads is to plan and build which are adequate enough for farm management and to transport farming material and products.
The scale of the farm and its management and what kinds of produce will be cultivated over at least ten years have to be considered before the planning of road reconstruction can be undertaken.
In many cases, the reconstruction plan of rural roads are apt to be designed for ordinary traffic and mainly evaluated by the number of vehicles passing over them. The reconstruction plan should take in to account the type of traffic used for agricultural purposes.
First, this study deals with the introduction of the investigation method and analysis of the type of traffic on rural roads; secondly, how to apply a farm calendar in the designing of a blueprint road network, then applying the computation method to the real models of a traffic integration system.
The results are summarized as follows.
1) The amount of daytime traffic (from 0700-1900 hrs) may well be estimated as less than 500 vehicles in agricultural trunk roads for orchard fields and upland green vegetable fields with very few exceptions.
2) The group of corn fields (A class, in Table 1) and Hokkaido have more traffic except cars for riding against the number of benefiting farmers than other examples.
3) A linearity between the number of benefiting farmers living in a village and total number of vehicles except cars are observed on road leading to the village from their farms.
4) The relation between the farming patterns and the type of traffic on the farming roads is not so simple that it could be safely said there is no relation between them though it was expeted.
5) The daytime traffic can be estimated as
N=αN (1000, 1500hrs)
where N is the traffic in the daytime (0700-1900 hrs), N (1000, 1500 hrs) is the mean hourly value at 1000hrs and 1500hrs.α is a constant 13.3.

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Theoretical analysis of the orientation of water molecules absorbed in clay was discussed in the fourth report. In this paper, the author obtained the N. M. R. spectra of the proton by using Kaolinite clay and changing ω°. Quantity ω is the angle between the direction of the magnetic field (H₀) and the normal to the sample. The second moments were calculated experimental from the N. M. R. spectra.
The theoretical second moments, however, were calculated from the orientational specimen of S. B. Hendricks etc. and H. H. Macey's model. Theoretical values did not agree with experimental results (Figs. 5, 6, 9 and 10).
Next, the theoretical moments were calculated from the orientational specimen of the author's model and they agreed well with the experimental results (Figs. 15 and 16).

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This is an investigation on the vibrational response and the failure process of a fill-type dam using a model with a shake table. The model dam used has a two-dimensional cross section and compared to the prototype it is 1/100 in scale. The materials in the random and core zone are compacted almost to the same degree as the prototype.
The testing procedures mainly consists of (1) dynamic response measurements to the sinusoidal waves and seismic motions, which are digitally condensed in the time domain to one-tenth, that of actual earthquakes with different frequency characteristics under a maximum input acceleration of less than 150 gals, and (2) failure tests by those motions augmented to 300-500 Gal.
After giving consideration to the model test and the corresponding similitude law used in the present investigation, the detail features of the experiment are described. Then, the results obtained are examined taking into consideration the fundamental response characteristics and the failure process. In the former part, the effect of the sidewall on the response is discussed and then the shear beam theory is applied with respect to the fundamental frequency and also the results are compared with those of the two-dimensional FEM analysis. In the latter part, the failure process including the slope slides referred to actual dam failures which have already occurred in Japan.

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The author arranged the basic equations of two and three-dimensional consolidation using a highly generalized method, and converting them into the finite element equations. The author denoted the method of elastic consolidation analysis which could be calculated in any boundary condition and by any material constant. Then, the author denoted the concrete formula using the L. S. T element model in the plane strain condition. Moreover, using the computer program that was developed, the author executed the calculation practically and ascertained the validity of the finite element analysis, comparing the computational results to the usual one-dimensional consolidation theory and Biot's theory, and explained the characteristics of the two-dimensional consolidation definitely.

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In a series of studies, the seepage failure problem of a piece-wise homogeneous sand column caused by a vertically ascending seepage flow was considered. In this paper, based on the previous papers, whether the assumption that two-and three-layered sand columns are homogeneous is reasonable or not is discussed.
The behavior of a critical position within a sand column is also considered in the two-and threelayer cases: When a critical position is in the topmost layer or in the middle of a sand column, a critical position within the sand column goes down from that position and finally reaches the bottom of the sand column as p (=effective overburden pressure of a loaded filter) increases. p₁c min (≥0) is defined as p at the time when the bottom of a sand column becomes, first and foremost, critical at a critical time as p increases, i. e., when the effective stress at the bottom of a sand column becomes, first and foremost, zero at a critical time as p increases. p₁c min is called the minimum effective overburden pressure of a loaded filter with which a sand column is critical at the bottom of the sand column.
Using the p₁c min value, which a piece-wise homogeneous sand column has uniquely:
From a point of view of an h_c value which is the critical difference in total hydraulic head between the topmost position and the bottom position of a sand column, the assumption of homogeneity is;
(i) 0≤p<p₁c min, unreasonable, or, on an unsafe side,
(ii) p≥p₁c min, reasonable.
That is, whether the sand column becomes critical at the bottom of the sand column or not corresponds, uniquely, to whether the assumption of homogeneity is reasonable or not. The assumption that the sand column is homogeneous is equivalent to the assumption that the sand column becomes critical at the bottom of the sand column at a critical time.

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