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Grant amount：\1100000 （ Direct expense: \1100000 ）

森林に出かけ、木々の緑を見たり、鳥の鳴き声を聞いたりして、開放感を感じるのは私だけではないと思われる。これは、森林とじかに「ふれあう」ことにより、日常の精神的、身体的なストレスをとることができるからではないかと考える。そこで森林とじかにふれあうことにより、脳波、脈拍、血圧、体温などの人体生理がどのように変化するのか測定した。また、森林のビデオを鑑賞している状態についても同様の測定を行ない、じかの森林にふれた場合との比較を行った。
平常状態、人工林および天然林のビデオを鑑賞している状態、実際に人工林および天然林にふれた(入った)状態における脳波、脈拍、血圧、体温の測定を行った。脳波の測定は4分間行い、1秒間毎の波形をフーリエ解析し、周波数スペクトル分析を行った。4〜6Hz、7〜8Hz、9〜11Hz、12〜13Hzおよび14〜23Hzをそれぞれθ波、スローα波、ミッドα波、ファーストα波およびβ波と呼び、それぞれ瞑想・浅い睡眠状態、リラックスした意識低下の状態、リラックスした意識集中の状態、緊張した意識集中の状態および緊張した意識分散の状態を表している。フーリエ解析により1秒毎の支配的な脳波を求め、その合計の時間を算出した。被試験者は9名で、19歳から44歳であり、男8名、女1名であった。上記いずれの状態においても、もっとも支配的な脳波はスローα波、ミッドα波、θ波のいずれかであり、個人により異なっていた。つまり、一定の傾向は示さなかった。また、血圧、脈拍、体温の変化も、森林環境の相違よりは個人差の方が強く、やはり一定の傾向を示さなかった。今後は、平常状態から異なった状態、つまり人工林や天然林に入っていくにつれて人体生理がどのように変化していくのかを測定する必要があろう。

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Grant amount：\2000000 （ Direct expense: \2000000 ）

The procedure to measure MOE (Modulus of Elasticity) of planting stock was examined. And breeding of selection by MOE was studied. The relationships between MOE and diameters at stem base and tree height of planting stock were investigated. The results are summarized as follows :
(1) MOE could be calculated from the deflection caused by adding weight to planting stock supported by two points.
(2) Planting stock of growth have smaller MOE than those of good growth.
(3) But there are some planting stock of good growth have large MOE.
(4) And the planting stock have larger MOE at first year have larger MOE at second and third year.
(5) Accordingly it is possible to select and breed them by means MOE.

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Grant amount：\2100000 （ Direct expense: \2100000 ）

The report in cludes the results of analysis in the reseach on Variation in the characters of Abies sachalinensis associated with altitudinal gradients at Tokyo University Forest in Hokkaido. As follows ; (1) Variation in growth respons of seedlings in eighteen years, (2) Growth characteristics, (3) Wood quality (4) The growth and flower setling, (5) Disease damage.
In addition to studies, (6) The relation between age of first cone setting and tree size of Soghalien fir planted tree, (7) Growth and flower setling of grafted clones of Saghalien fir from two soarces at high and low altitudes, (8) Growth and flower setting of the top budded clones of Saghalien fir, (9) Growth of hybrid progeny from crosses between two sources at high and low altitudes, (10) Regeneration by natural layring Saghalien fir the forest line, (11) The Genetic variations in natural stands of Saghalien fir.

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Grant amount：\6400000 （ Direct expense: \6400000 ）

Wood waste from wood industry, even that from demolished house, has been originally used for chip and fuel as a recycled raw material, but it recentry tends to be dumped or burned as rubbish. This project aims to re-use the timber from demolished houses and used wood products effectively. Based from the results of this study, the following conclusions could be drawn :
(1) Wood chip from the timber of demolished house was used for particleboard. The quality of the particleboard was equal to that from virgin wood chip.
(2) Recovery of wood preservatives was investigated by burning and heat degradation. This method could be useful as a tracing testing.
(3) A rapid carbonizing method for used timber was investigated. A variety of used timbers, such as used colomn, glulam, chip, saw dust and decay wood, were carbonized, and then their ability of absorption and wettability tend to be increased in increasing carbonizing temperature.
(4) Wood residu in forest was carbonized and the charcoals were spread into forest.
(5) The bio-degradation and photo-degradation of poliyurethane foam from liquefied wood is easily accelerated. This composite is recognized to be less environmental impact.

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Grant amount：\8000000 （ Direct expense: \8000000 ）

Wood waste has been originally used for chip and fuel as a recycled raw material, but it recently tends to be dumped or burned as rubbish. This project aims to re-use the timber from demolished houses and used wood products effectively. Based from the results of this study, the following conclusions could be drawn :
(1) Wood chip from the timber of demolished house has been used for particleboard. The quality of the particleboard was equal to that from virgin wood chip.
(2) A rapid carbonizing method for used timber was developed. The two step carbonization could be more effective for removing nails and so on and for refining the charcoal.
(3) A variety of used timbers, such as used colomn, glulam, chip, saw dust and decay wood, were carbonized, and then their ability of absorption and wettability tend to be increased in increasing carbonizing temperature.

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Grant amount：\2000000 （ Direct expense: \2000000 ）

木質構造の他構造と著しく異なる点は接合の“あそび"と局部塑性およびせん断や割裂ようなぜい性破壊が混在することにある。接着接合は一般に変形が少ない剛なものとしてみられる反面、ぜい性なものととらえられている。また、釘やボルトなどの機械的接合では、初期の段階から局部的な弾塑性を介し、木部の圧潰が生じるときは塑性的で、比較的粘りのある抵抗を有するが、せん断や割裂が主体になるときわめて脆い性状を示す。したがって信頼性に乏しく、剛性の低いものとして安全率をきわめて高くすることを余技なくされている。本研究ではぜい性破壊の生じやすい接着接合に“あそび"の少ない機械的接合を併用した粘りを付与した場合と、機械的接合部に粘着剤を併用し瞬間的な力に対する剛性と破壊エネルギ-の増加、局部に集中させないでぜい性破壊の生じにくくさせた場合を検討した。
1.接着接合にラグスクリュウによる“あそび"の少ない機械的接合で粘りを付与したときは接着接合にみられる急激なぜい性破壊は緩和され力の伝達をスム-ズに局部圧縮のような塑性機構に移行させることが可能であることを認めた。併用接合の場合、フェイルセイフとして評価が可能であると思われるので、接着接合単独より許容耐力をあげる設計概念が考慮されるべきであろう。
2.機械的接合に粘着剤を併用すると粘着剤の粘弾性特性によって短時間では接着接合にみられるように伝達される力が全面に分散されるので局部的な力によるせん断や割裂といった脆さが緩和される可能性が認められた。また、接合部に減衰付与機構をもたすことは粘着剤の粘弾性特性によっているので、今後木構造の接合部に作用する力に対して分子設計で粘弾性の特性を変えることによって、その破壊形態と許容耐力評価体系への対応を考察する必要があろう。

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Grant amount：\5800000 （ Direct expense: \5800000 ）

Studies were divided into following two subjects.
I. Shearing properties of wall frameworks composed of LVL posts with hollow cores Shearing tests of wall frameworks fixed with long bolts were conducted.
Experimental results are summarized as follows:
* The rising of the post where the lateral load was applied and sinking of the opposite side was so small that the rotation of the wall was almost equal to zero.
* When a post was subjected to lateral loading, the post remained straight and did not bend. Consequently, the post resistance to the lateral load may have been due to the partial compression strength generated at the bottom of the post towards the horizontally attached sill and girder. For this reason, the shearing strength was smaller than expected.
II. End jointing of glue-lam beam and bending properties of the jointed beams. Larch glue-lams with two or four holes longitudinaly on the cross section were end jointed by finger jointing and fastened with long bolts. These end jointed beams were tested by four points bending. The MOE was shown to be increased by the moment at the both ends of the beam which generated by the tensile stress of the bolts. Also, the MOR of the jointed beam increased. After the failure of finger jointing, the beam still keeps a load bearing capacity to a certain extent on account of the existence of bolts. This system is recognized to be safe and very reliable.

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Grant amount：\9100000 （ Direct expense: \9100000 ）

Concrete form plywood Is removed from hardening concrete and Is damped or burned as rubbish. Damping and burning wood has been a sdrious problem as a loss of wood resource and release of carbon-dioxide to air. This project focussed on stocking wood resource In reinforced concrete structure and Improving llvlng condition of the structure by not removing wood-based materials for concrete form.
(1) Bonding strength between wood-based materials and concrete, the behavior of water during -concrete hardening was measured. Wood-based materials such as plywood for concrete form and wool cement board might be effective for anchor effect. Velocity of stress wave and ultra-sonlc wave was effected by hardenlng of concrete and release of water. (2) Existence of wood-based materials after concrete hardening has effect for protecting condensation on the surface, Improving Insulation and control of humldlty In the "space.
(3) Fire protecting by wood-based materials was investigated. The rate of burning of wood-based material might be delayed by combination effect in concrete placing.

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Grant amount：\4400000 （ Direct expense: \4400000 ）

The aim of this research is development of on-line quality control systems in forest products factories in order to elevate the reliability of construction parts and materials for timber engineering. Methods of the proof testing of materials of woody panel, such as lumber and plywood, and wood adhesive were investigated, specially, grading of lumber by using acoustic emission (AE), nonーdestructive testing of plywood and wood adhesive and measurement of moisture content by using time domain reflectometry method. These trial machines were produced and tested, and the practical usefulness of the Methods were estimated.
1. The AE grading using an AE wheeled sensor could detect and evaluate strength-reducing lumber defects such as knots and closs grain, and it is more reliable than the current visual grading system based on knot ratio. The AE grading could also detect rots and checks. Therefore, reliable AE lumber stress grading can be realized by using AE to detect defects in lumber in conjunction with the more traditional MOE classification. 2. Two types of AE testing machines were produced for the purpose of inspecting defects in plywood boards (900x100mm) and floor boards. Delamination in the boards could be detected and evaluated by the machines. 3. Wood moisture content measuring system based on TDR method was developed. It is including hardware (a computer, a generator and a wave memory) and software (a control program and a wave form analysis program).

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Grant amount：\6500000 （ Direct expense: \6500000 ）

Timber construction has clearance and gap between holes and fastener in the joint. In this project the behavior of joint with gaps and structural frame were experimentally and theoritically evaluated. The results obtained were as follows.
1) A wide distribution of gaps leads to a large variance in the stiffness of joints. When the number of units which compose joint increases, the average of stiffness per unit decreases, but the variance tends to be small.
2) The modulus of elasticity of beam with pressure sensitive adhesive is small, but its dynamic elasticity is equal to those with resorcinol adhesive and nail joints. The damping constant and impact absorptive energy to failure of beam is a little larger than those of other joints.
3) Horizontal load and dynamic test for wood bearing wall with braces was carried out and analyzed by models using elastic spring and rotation spring for joint. It shows that deformation of joint could strongly contribute to the total deformation of wall.
4) Truss construction using ball-joint was applied to static and dynamic horizontal load and was analyzed by modal analysis method. Data indicated that this method could be applied in the analysis for struss construction with gaps.

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Grant amount：\5200000 （ Direct expense: \5200000 ）

The modulus of elasticity (Et) of log was determined by measuring the natural frequency of longitudinal wave due to sound when hitting cross section. The Et of laminae and post-sized lumber with pith produced by the log were also measured. Results were as follows: (1) Et was recognized to be highly linear to the modulus of elasticity due to static bending test(Es).The third-term natural frequency of longitudinal wave was hardly affected by piling in stock yard as compared to the first or second ones,thus longitudinal wave sound analysis could be considered as a reasonable material selection and control system. (2) Since the Et of post-sized lumber and the average value of Et of laminae was recognized to be highly linear to Et of the original log, this rough classification of log could be useful in the selection of raw materials for structural lumber and glue-laminated lumber. (3) Since changing of natural frequency during drying process was affected by the increase of Et and weight loss due to desorption of water,it might be effective as rough quality control of drying within a well-known increase of Et. (4) In the glue-laminated lumber mill, the classification of log was conducted by longitudinal wave sound analysis. It could be efficient as a reasonable selection system for laminae.

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Grant amount：\4000000 （ Direct expense: \4000000 ）

An effective nondestructive test is strongly necessary to develop the grading system of the structural members (sawn lumber or wood-based materials) in the wood construction. In this study, several kinds of nondestructive tests were applied to the wooden materials to investigate the possibilities and the conditions as the testing method for the strength grading system.
Results of the study are summarized as follows ; (1) Static bending by dead load, dynamic bending, stress wave and sound analysis tests were considered as nondestructive testing methods to get MOE of the specimen. Also, acoustic emission tests and image analysis method were taken up to inspect the defect of wood. The data from these tests will serve for the conservative visual inspection. (2) Every methods have their own limitations in the practical application to the structural grading of wood and the combination of these test methods seemed to be very effective. (3) Moisture content of the material has a great effect on the value of nondestructive test. So, a prediction method of moisture content was proposed. Moisture content can be calculated from the weight and the volume of wood by this system. (4) A plenty of data of MOE and MOR were provided from each forestry institutes, and the relationship between MOE and MOR was investigated. And then, this relation was analyzed in the way of reliability theory for its application to the strength grading system.

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Grant amount：\2000000 （ Direct expense: \2000000 ）

In Japan, it is required to produce some new structural sheet materials from low grade components of the domestic plantation timbers. LVB (laminated veneer board) which is composed of small sized veneers such as 45-90cm both in length and width has been considered as one of the substitutes for lauan plywood.
The strength properties of HINOKI (Japanese cypress) and SUGI (Cryptomeria) LVB were investigated. Tests results are summarized as follows;
1 The MOE of LVB is almost the same as that of lauan plywood.
2 There is no effecto of the end joints of the veneers on the MOE of the products.
3 Both the MOE and the MOR of HINOKI LVB are larger than those of SUGI LVB.
4 HINOKI LVB 13.7mm thick is not at all inferior to 12.5mm lauan plywood, and is for better than 15mm particleboard in bending performance under a concentrated load.
It is possible to fully automate the processing line by fitting it with robots for arranging the small veneers.
Generally, LVB can be manufactured from the domestic grown soft-woods efficiently and was found to have sufficient strength.

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Grant type：Competitive

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Grant type：Competitive

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Grant type：Competitive

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Grant type：Competitive

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