In this paper approximate, equations on the drain hydrographs of the growing vat have been expressed so that the mathematics following can be handled easily, and a rational design for drain pipes from the relations between elapsed time and discharge have been prepared by considering, the flow in the drain pipe to be a quasi-uniform in a circular channel.
The results obtained are summarized as follows:
(1) The approximate expressions of the hydrograph on outflow from an overflow type spillway in the vat are given, and the corrections to be made when supply time and liquid surface area in the vat differ are also given.
(2) The design procedure that gives hydraulically the most efficient cross-sectional area (diameter d=1.066 h_max) for the maximum discharge in each section between lateral inflows for, the drain pipe flow expressed as a quasi-uniform flow of the circular channel are shown.The changing flow in the pipe can be made known by this procedure.
(3) The flow of the drain pipe using the above most efficient standardized pipes, whose d is gradually increased the more downstream, it is nearly results in the depth h for the maximum velocity, or h=0.813 d.This is a desirable design judging from the function and freeboard of the drain pipe.
(4) The material cost (as a PVC pipe) of this composite drain pipe is 30-37% cheaper than that of the existing simple drain pipe.And a standard-length of 4 m is better for the section length of the composite pipe (equal to the distance between separations in vats).
(5) The most efficient cross-sectional area of the drain pipe can be determined more safely and easily by using only the maximum inflow (discharge) from the vat.

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Using a broad line N. M. R., the strengths of local magnetic fields were determined which the hydrogen atoms of allophane clay's structural hydroxyle (OH) and its absorbed water receive due to the effects of nuclear spins of such surrounding materials as other hydrogen atoms, aluminum atom nucleus, etc.The followings are the summary of findings from these determinations.
(1) Local magnetic field of dry allophane clay at the room temperature.
The local magnetic field which the hydrogen atom of hydroxyle (OH) of dry allophane clay (treated at 110°C for 24 hours) receives at the room temperature, is small with 1.75 gauss, compared to 5.0 gauss of kaolinite clay and 4.8 gauss of montmorillonite clay under the same condition.
The value of index X which indicates the activity of the hydrogen atom, is very high with 3.3 in case of allophane clay, compared to 1.26 of kaolinite clay and 1.12 of montmorillonite clay.This implies that in allophane clay active hydrogen atom exists under the tested condition.
(2) Relationship between local magnetic field and absorbed water of allohane clay at the room temperature.
As seen in above (1), the dry allophane clay (treated at 110°C for 24 hours) having pF value of 7.30 gives the local magnetic field of 1.75 gauss.It gradually decreases as the pF value drops (absorbed water increases), and finally reaches the bottom point of 0.7 gauss with the pF 4.46 sample where the absorbed water gets saturated.
In allophane clay, there is no stepwise change of the local magnetic field due to the thickness of the molecule layer of absorbed water, as seen in cases of kaolinite clay and montmorillonite clay.
(3) Relationship between local magnetic field and temperature of dry allophane clay.
The local magnetic field which the hydrogen atom of hydroxyle (OH) of dry allopharie clay (treated at 110°C for 24 hours) receives, begins to increase from around minus 5°C foward lower temperatures and reaches 5.0 to 5.2 gauss at around minus 100°C.It remains almost flat down to minus 175°C. This indicates that the activity of the hydrogen atom of the hydroxyle (OH) becomes constant at around minus 100°C.
(4) Relationship between local magnetic field and temperature of allophane clay having 1 to 2 molecule layers of absorbed water.
The local magnetic field which the hydrogen atom of allophane clay having 1 to 2 molecule layers of absorbed water receives, begins to show a sudden increase at minus 55°C foward lower temperatures and becomes constant at around minus 150°C.In case of kaolinite clay having the same molecule layers of absorbed water, it becomes flat at minus 130°C.

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A mathematical model for baseflow phenomenon from a small mountain-basin is studied and how it should be applied are discussed.
This model consists of three different subsystems, namely the soil layer system which has the function of dividing rain water among each runoff component, the rock layer system which has the function of transmitting soil moisture from the soil layer system to the aquifer system, and the aquifer system which has the function of storage and discharge of ground-water.
The characteristic parameters of this model are reasonably and easily estimated using rainfall and runoff data.
The estimated values of baseflow component from a small mountain-basin by this model almost coincide with the observed values.

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In the planning and desiging of peat soils, many difficult problems remain unsolved since each kind of peat soil shows its own individual physical and mechanical properties.
The author reports the results of various measurements of the shrinkage of the peat soils in the Tohoku District, and discusses these in this paper.
To clarify the problems involved the author has proposed a shrinkage model for peat soils consisting of fibrous and nonfibrous components.
On the basis of several experimental studies on the shrinking characteristics of the peat soils, the following has been made clear.
(1) As seen from the slope of the shrinkage curves (Fig.2), the rate of vertical shrinkage gradually increased at the low pF, while that of horizontal shrinkage did not very much.This can be explained by the fact that the fibrous component accumulated in the horizontal position.Air enters the peat soils as the water content becomes less, and the total volume decrease was lower than that of normal shrinkage.
(2) At a high pF (more than about pF 3.5-4.0), the rate of horizontal shrinkage increased rapidly, thus the total volume decrease was more than the water loss.This phenomenon is explained by the shrinkage on the fibrous component.

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In agriculture, there are times when irrigation is needed and not neeeded.Therefore, due to this fact pipelines used for agriculture have more occurrences of air being entrapped within them than ordinary piping.
When observing the bulk coefficient of elasticity for water and air, one will notice that they have extremely different characteristics.Water is considered to be an incompressible fluid, but on the other hand, air is a typical compressible gas.
As a result, the water-hammer effect occurs differently when air is in the pipeline as opposed to when it is not.
In examining the safety of pipelines, it is important to know that the maximum water-hammer pressure that will occur when air is mixed with water.
Air is often used in controlling the water hammer effect, however, it is said that air has a dangerous influence on the water hammer effect.
But up until now there is no information about exactly what is actually dangerous and how it affects the system.
In this paper, we have taken on the task of study agricultural pipelines that have air entrapped within their systems and have made an all-out effort to solve the problems derived from this phenomenon, so as to reduce the water-hammer effect in piping.
The results obtained are summerized as follows:
1) The method of theoretical estimation for maximum water-hammer pressure in cases where air has been mixed in with the water is stated.A comparison of theoretical and experimental values are shown in Fig.10.
2) Characteristics of maximum water-hammer pressure in relation to the place where the entrapped air and water have been mixed, it's length, air content ratio and the closing time of the valve are shown in Fig.11, 12, 13 and 15.

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Large-scale soil dressing by hydraulic power requires various soil crushing devices not only to crush soil by water jet, but to disperse, sort, and crush soil in mud water so that mud may be smoothly transported to remote places.Precise knowledge of their performances is thus considered as important as their installation itself.
In the present work, the performance of the soil crushing plant in Akasobu area of the Tonami (Toyama Prefecture) soil dressing project with mud water, the largest project of its kind in this country, was closely watched for the period of three years;the results were examined on the basis of newly defined effective pass percentage of grain size (C_n) and difference in effective pass percentage of grain size (f_n, f'_n).
Using cn, the concentration of mud (m) and the grain size distribution can now be uniquely correlated; the relationship between the input and output flows is obtained unambiguously from comparison of the corresponding m-c_n plots.The use of f_n and f'_n enables one to quantitatively assess the performance of each soil crushing device.
The results obtained indicate that the soil crushing performance depends greatly on the mud concentration; data relating to the performance and mud concentration necessary for designing various soil crushing devices have thus been obtained.

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As part of the study on land reclamation and consolidation for farmland in the tertiary type landslide area, the amount of slaking in the bedrocks of the tertiary type landslide was studied, in the light of the nature and physics of soil, in relation to the mechanical and physical characteristics of the bedrocks.The experimental results obtained with the rock samples were first interpreted and analyzed according to the existing theories;some of the phenomenon observed, however, were found not to be explained.
In the present work, the amount of slaking was examined in conjunction with the shrinkage characteristic as well as the degree of soil structure development. The following are new insights gained in the present work:
(I) Relation between Shrinkage Characteristic and Amount of Slaking
Soft rocks undergo three types of shrinkages, i.e.normal, structural, and residual shrinkages;the development degree of each varies with each soft rock.When the degree of drying shrinkage per unit moisture content of a rock in a state of an undisturbed sample is expressed by the coefficient of shrinkage change (k), the following relation is obtained between the amount of slaking and the shrinkage.
i) If k_max=0.3 to 0.5, normal shrinkage, or shrinkage closely related to it, occurs first and is followed by residual shrinkage.A soft rock with such a shrinkage characteristic has a large amount of slaking (group A and B in Table 4).
ii) If structural shrinkage continues until a fairly low moisture point and residual shrinkage that follows has k_max nearly equal to or less than 1, the amount of slaking is small (group C in Table 4).
iii) If k_max has an intermediate value between the above two, the amount of slaking is also between those of i) and 11).
(II) Relation between Soil Structure and Shrinkage Characteristic
If R, a parameter indicating the degree of the structural development of soil, is large enongh, structural shrinkage takes place, followed by a shrinkage process whose characteristics are given in the following:
i) Normal shrinkage, or shrinkage closely related to it, occurs followed by residual shrinkage.This applies to rocks belonging to group A in (I) i).
ii) Residual shrinkage takes place to a small extent;this applies to rocks of group C in (I) ii).
If R is small (R=1 to 2), practically no structural shrinkage is observed, and normal and residual shrinkages start immediately.This applies to rocks of group B in (I) i).
The above correlation between the rock characteristics and the amount of slaking led the author to propose classification of rocks and soils for various soft rocks.Interpretation of slaking from the angle of soil physics is as follows: if the degree of drying shrinkage per unit moisture content is large that is, if soil grains greatly changes their positions relative to one another, the corresponding soft rock will bave a large amount of slaking: under such dried conditions, silica acid gel films inaccessible to water molecules tend to crack and cause slaking.

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Complex damping model was proposed in the previous paper, representing both viscous and hysteretic damping forces developed in a vibrated system.This model is now applied to the dynamic analysis of an actual dam, Nakasato Dam, which is one of the largest earth dams in our country.
During a small earthquake of Aug.6, 1977, seismic response was recorded by the instruments buried at several points in the embankment.Comparing the records with the results analysed using the proposed damping model, an appropriate agreement was obtained except for some differences in the amplitude of the absolute acceleration at the crest, probably caused in idealizing the structure.
This paper consists of the following three parts:
(1) Explanation of the complex damping model and the procedure for the application to the analysis.
(2) Details of static and dynamic analysis procedures used in this investgation in relation to other procedures.
(3) Comparison between the records and calculated responses.

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In the previous paper (1) the authors conducted an embankment microtremor measurment at Iya Reclamation Land under construction, Naka-Umi Polder Reclamation Project, Shimane Prefecture, and decided on particular site of the embankment for making calculation of vibration.In this paper, the authors first investigated the characteristics of the measured seismic accelerograms and used these for response calculation.Secondly based on the various earthquake data on the site during more than last one hundred years, the authors computed the maximum acceleration value of a one hundred year probability and calculated the response values under the estimated magnitude to take into account the characteristics of measured accelerograms and discussed the possibility of liquefaction etc. The results are as follows;
(1) Measured seismic accelerograms considerably show nonstationary state.The authors conducted response calculation using these, so that it could be shown that the proposed model is capable of calculating the response values and taking the time history of measured record.
(2) As results of the response calculation of a so called'one hundred year probability earthquake', it was shown that nonlinearity and non-homogeneity of the vibration system affect the response values, and it is clear that the shear strain and shear stresses do not become great enough to harm the embankment.

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The author has already reported on temperature variations in a concrete slab by meteorological action.
This paper deals with temperature strains in the slab produced by these temperature variations.The analysis of the temperature strains was carried out using the theory of elasticity by Timoshenko.
The results are as follows:
1) Temperature strains due to restrained warping (ε_w) produced maximum tensile values of about 13 on the back surface of the slab on fine days.[Fig.4 (B), 5]
2) Temperature strains due to longitudinal restraint (ε_L) were large according to calculations. Cracking is usually safe because of the small restraint ratio.[Fig.4 (A), 6 (A)]
3) ε_w grew to nealy a limited value of tensile strain (ε_lim) during May and June and thus there was the danger of cracking when slab was under strong restraint.[Fig.6 (B) ]
4) Temperature strains due to internal restraint (ε_I) were ordinarily small;however when the temperature of the slab surface fell suddenly, fairly large tensile strains occurred on the surface.[Fig. 4 (C), 6 (B) and 7]
5) The maximum temperature strains (εW_max and εI_max) differ according to the thickness and coefficients of thermal diffusion of the slabs.[Fig.8, 9 and Table 1]

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[in Japanese]

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