Aggregate test, mortar test, concrete test and manufacture test of secondary concrete products were executed in order to examine whether the coal ash slag can be used as a fine aggregate for concrete. As a result of these tests, the coal ash slag turned out to be similar to the pit sand in ingredient composition without any toxic chemicals to be eluted and after being subject to grinding process, it satisfied the quality requirements as a fine aggregate for concrete. The greater the slag substitution rate is, the greater the bleeding rate of the concrete using coal ash slag becomes. However, the concrete using coal ash slag has almost equivalent the compressive strength and tensile strength to those in which the land sand is used. Concerning the characteristics related to durability, such as the carbonation rate and freeze-thaw resistance, it did not show any difference from the concrete using the land sand. With these results, it can be concluded that the granulated coal ash slag has a quality to be applied to structural concrete.

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Shrinkage cracking controlling design scheme has been proposed by authors and allows us to estimate shrinkage cracking risk of planer R/C members constructed with regular concrete. This study focused to extend this scheme to involve shrinkage crack reducing concrete added expansive additive and shrinkage reducing admixture (NES, hereafter). This extension was achieved by modifying shrinkage restraint stress analysis model, in which recently developed creep model for NES was incorporated. The modified model was verified comparing with strain behavior of real slab members restrained by steel beams, with which the slab members' behavior was successfully reproduced. However, the model was found difficulty in predicting slab behavior constructed on soil foundation due to complexity in estimating restraint degree against the slabs. As an initial step to solve this problem, the restraint degree was analytically identified with the model for the first time.

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The crack width due to drying shrinkage of RC members is calculated by integrating a difference of strain of reinforcing steel and concrete along bond loss region. This value is correspond to the multiply of the equivalent bond-loss length(L_b) and the sum of the strain of reinforcing steel and concrete at the crack. If L_b is used, crack width can be simply calculated. In this paper, a parameter study was carried out by the bond analysis to investigate the influence of several variables on L_b, and the estimation equation of L_b was proposed. Parameter study (reinforcing steel ratio, concrete strength and so on) was carried out by using L_b to investigate the effect of crack width due to drying shrinkage.

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This paper shows deterioration models due to carbonation in consideration of uncertainty to estimate the initiation and the rate of corrosion, and to analyze the structural capacity and serviceability of RC building, i.e. shear capacity, bending strength and width of severe cracking or spalling of columns and beams with corroded reinforcing bars based on simple formulas formed through the past experiments. Then, the failure probability due to earthquake, the probability that severe cracking or spalling will occur and the deterioration risk of deteriorated building in subsequent years from construction can be evaluated by probabilistic method. By applying immune algorithm to minimization of life-cycle cost including the deterioration risk, the optimal maintenance plan of reinforced concrete buildings can be found and a case study is finally conducted to prove this system.

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The purpose of this paper is to find out quantitatively the relationship between the surface shape and the mechanical properties of corroded reinforcement. Three-dimensional measurements were carried out on the surface shape of variously corroded reinforcements and parameters expressing the characteristics of the shape, which included the maximum decrement of sectional area of reinforcement, its distribution along the axis and the power spectral density by the Fourier Transformation. It was investigated that which parameters could correspond to the mechanical properties of corroded reinforcement and it was confirmed that the maximum decrement of sectional area of reinforcement could express the mechanical properties most appropriately. Finally, this paper proposes a constitutive model of corroded reinforcement for analyzing the structural behavior of reinforced concrete structures considering the localized corrosion of reinforcement by finite element method.

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This study establishes the measurement method of the slipperiness by pets. This study is necessary to clarify the method to evaluate safety of pets. First actions are interview to the animal doctors and experts at houses, the selection of subject pets (“Dog” is selected.), and collection of information about soles of dogs. Next, angles θ₂ which the subjects start to slip are searched by ramp method with 16 subject dogs and 16 kinds of floor samples. Then, coefficients of slip resistance (C.S.R') of the floor samples are searched with ONO · PPSM (ONO · Portable Pull Slip Meter) by various slider materials and vertical loads (W). Also, the relations are investigated between these C.S.R' and tan θ₂. As results, it is an appropriate measurement method of slipperiness of dogs to use a slider material with hemp fabric over foamed rubber sheet and W=49N.

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Requirements of the traditional plaster works and techniques using mud wall materials have been kept changing year by year from a standpoint of social, economical and environmental aspects. On the other hand, a traditional plasterer using mud wall materials as one of the building finishing materials has an important role to fulfill the user's requirement on the visual color properties and the surface texture of the building walls. In this research, a color compounding mixing design method of mud walls finishing materials is proposed by the experimental approach. As a result, the relationship between the tristimulus values X, Y, Z of the material surface color and the mixing conditions of mud wall materials is cleared experimentally, and the formula to express the surface color of mud wall finishing with parameters of the color, the average size and the weight ratio of mixing soil particles was proposed.

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Even though the same concrete is used, the amount of execution effort affects on surface quality of floor groundwork and performance with covering material. In the previous thesis, covering materials are executed on groundworks with different surface quality. The thesis shows relations among execution effort of the groundwork, flatness and work for repairing and maintenance.
This thesis reports in-depth consideration based on durability against caster-load and thermal-shock. The result shows that the total work of maintenance is cut down because the more effort of groundwork is spent, the higher durability is realized and the less work of maintenance is needed.

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This paper presents numerical evaluation on interaction mechanism between three-dimensional square prism and wake. The purpose of this discussion is to propose numerical model for the simulation of vortex-induced oscillation or aerodynamic instability such as galloping. New parameter related to wake stagnation point in the averaged wake field obtained by PIV (Particle Image Velocimetry) measurement was introduced on the modification of the past wake-oscillator model. The result of numerical analysis by the proposed model showed that it was agreeable with the result of past wind tunnel experiment and it can be applicable to the condition of not only uniform flow but also turbulent flow.

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Typical steel moment-resisting frame structures in the United States, similar to many super-high-rise framed-tube structures being constructed in Japan, have stiff beams and columns only around perimeters and often have none or few seismic beams inside the building. The lack of strength and stiffness of connections between perimeter frames and floors to support the out-of-plane behavior of perimeter frames may cause unstable behavior when perimeter frames are separated from the floors due to accidental or earthquake loading. This study analytically simulates progressive collapse when the attachment of perimeter frames to floors is lost and predicts the strength of the connections required to prevent progressive collapse during earthquakes.

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We performed a field survey of damage to wooden houses, tombstone overturning, and microtremor measurements within the near-source area of the 2007 Noto Hanto earthquake. Based on results of the field investigation, peak ground velocity (PGV) and the seismic response of wooden houses during the main shock are estimated in the source region. From the tombstone data, we estimated PGV values over 80-100 cm/s within the area. The maximum values of building drift evaluated are consistent with the damage statistics in the area, which could mainly be controlled by structural performance and strong ground motion amplified due to S-wave velocity profile and soil nonlinearity, i.e., local site effects.

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Two exterior CES beam-column joints with different failure mode, the beam yielding type and the joint shear failure type, were tested under lateral load reversals and variable axial load to investigate the structural performance. The test results indicated that the CES beam-column joins had the stable hysteresis behavior until large story drift angle of 1/20 radian. In addition, the use of the FRC facilitates to control the crack width of the joints. The development of stresses in the joint panel was clarified by the rosette analysis and non-linear FEM analysis. It is shown that the joint shear strength of exterior CES beam-column joints cloud be evaluated by the method based on AIJ design standard for SRC structures.

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The practical and simple analysis method is proposed for the earthquake response of the buildings supported on a large number of piles. The proposed model is based on the beam-on-spring model which consists of lumped masses, beam elements, horizontal soil springs, dampers and shear soil springs taking into consideration of pile group effects for the simplified method. The group-factor of horizontal soil springs is simply evaluated from the group-factor of a pile-soil system, and shear soil spring is estimated from the approximate equation. The accuracy of the proposed method is demonstrated by the simulation analysis of the observed earthquake record.

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An evaluation method of time history earthquake responses for the shear and drift of each frame in a multi-story asymmetric building is proposed to improve the seismic evaluation method of the Calculation of Response and Limit Strength. Both the time history earthquake response analysis and the modal adaptive pushover analysis, which is a static analysis, for a four-story reinforced concrete asymmetric building are conducted to reduce the building to two kinds of the single degree of freedom systems, the dynamic reduction system and the static reduction system. Using the responses of the dynamic reduction system, the first mode components of the shear and drift responses of each frame are evaluated. The higher mode components of the responses are also evaluated by the proposed method. The validity of the proposed method is demonstrated through comparing the predicted responses with the time history responses analyzed.

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Steel diagonal bracing systems combined with moment frame can develop a preferable resistance against earthquakes. Lot of research works have been made on the hysteretic behavior of bracing systems already. However, real responses of these systems to earthquakes have not been made clear yet.
In this paper, the distribution of the cumulative plastic strain energy (structural damage) in one story and the damage distribution between stories during an earthquake are made clear and a simple design formula based on the energy balance is proposed.

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A series of vertical load tests are performed on model piles with enlarged base bulb embedded in a medium dense sand filled in a soil chamber of 1000mm diameter. The model pile used is a nodular pile consisting of 114mm diameter double steel tubes with two nodes around the outer tube. The effects of the size and shape of the base bulb are investigated to find the behavior of the vertical load transfer and the fracture patter of the base bulbs. Detail measurement of strain gauges on the pile shaft show that the load share by parts of the pile varies with the increase of the settlement. The fracture pattern of the bulbs excavated after load tests explains well the measured load settlement characteristics.

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When we design the length of a cut-off wall, it is very important to consider an anisotropic permeability of the ground. The purpose of this study is to evaluate an anisotoropic permeability in macro area of the ground. Our proposed method is using an inverse analysis of FEM model with measurements of flowrate, and drawdown at construction site. It was examined about the application of the method to multi layer ground. And anisotoropic permeability was shown at 9 construction sites. Further, relation anisotoropic permeability and N number, fine fraction, or articles of boring suevey were shown.

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The target of this study is a wood-concrete composite floor deck system with shear connector. Though this composite floor has spread in European area, in Japan the use has been limited for the part of timber-based apartments and schools. The floor deck may spread in the near future because Japanese building standard law was revised and high performance is required for fire- and sound-proof. In this paper, the results of bending test and long-term loading test is described as a feasibility study. The result of shear performance of shear connecter between timber beam and reinforced concrete slab is also described. They are summarized in 1) the composite deck increases 50% in strength to superposition of individual strength and more than 500% in stiffness to simple timber beam, 2) the deformation after 50years reaches 400% against initial deformation which is extremely larger than simple timber beam, 3) initial stiffness of the deck is estimated using equations proposed in the past study, but it is necessary to consider the effective width of concrete deck.

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This paper proposes the evaluation method of seismic performance of shear resisting elements in timber construction with shear walls. Proposed new evaluation method uses two parameters of horizontal stiffness and potential energy of the shear walls. These two design values provide horizontal damage limit and safety limit strengths of stories that have equal quality to those by the summation of load-deformation curves of the shear walls. These strengths by this method have less variety than those by existing simple evaluation method. This method also provides Ds values of stories that consist of different type of shear walls. Ds values of the stories have not been provided by the existing simple evaluation method. Precise safety limit strengths and Ds-values of the stories realize to apply horizontal load-carrying capacity design method for the structures with different type of shear walls. This evaluation method would be possible to apply for other structures than the timber construction as a simplified method.

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In timber structures, the easy dismantling method and easy segregating method are required for reuse and recycling of wood, as the environmental disruption is the problem to solve. We designed the new connecting system using adhesive and bamboo connector. The joint part composed of bamboo connectors and adhesive can be cut easily by a saw or chain-saw. In addition, the separation of metal connector from wood at joint is not necessary for reuse and recycle of the connected wood in timber structure. In this study, the some tests were carried out to confirm the strength of joints using the new connecting system with the bamboo connector. High strength performance can be obtained from the test results by laminated bamboo connectors.

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The PRESTRESSED CONCRETE MILD-PRESS-JOINT method was proposed for controlling earthquake damage to buildings. It is expected to effective in future seismic designs. So far, Experiments were carried out on ┼ -shaped and ├ -shaped frames designed using this method. As a result, it clarifies the mechanical properties such as hysteresis characteristic, behavior of joint rotation prestressing strand for compression beam-column. However, there have been almost no experimental studies about column-foundation on this method. Thus, experiments of beam-column-foundation in frame structure which has foundation part and frame of cruciform using this method were carried out not only to obtain behaviour of joint rotation by prestressing steel bar compressing column-foundation and damege controlled effect against column-foundation, but also to study on the influence mechanical behaviour of the column-foundation to the frame with PRESTRESSED CONCRETE MILD-PRESS-JOINT. In addition, two-dimensional finite element analyses were carried out to investigate the stress state of the beam-column-foundation in frame structure.

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This paper presents a simple secant rotational rigidity evaluation formula for an exposed column-base that takes into account initial anchor bolt tensioning and column axial force. The applicability of this formula is confirmed through the loading tests and finite element analysis on a cantilever with an exposed column-base.
It is clarified that:
1. The rotational rigidity of a column-base varies with column axial force and initial anchor bolt tensioning.
2. The presented formula agrees closely with loading-tests results.

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The focus on performance-based seismic design in structural engineering has led to efforts to develop means of limiting inter-story drifts in structures. Recently, new systems have been developed to try to not only limit inter-story drifts, but also provide a self-centering capability to structures to limit residual deformation. However, little has been done in terms of compiling data on the effect which residual deformation has on the function of the structure and whether such self-centering systems are necessary. This study provides a review of construction tolerance for various building types and also presents the limited quantitative data currently available in terms of damage associated with particular residual drift levels after an earthquake. Further, the psychological effects which various inclinations can have on the human body are presented as these can provide serious serviceability concerns for a structure. Finally, a physical investigation of an occupied building structure is conducted to try to better quantify typical inclinations in building structures and the effect which they have on their occupants.

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U-shaped steel dampers are used widely for energy dissipation in base-isolated structures. However, dynamic loading tests of full-scale U-shaped steel dampers had not been conducted yet. Therefore, effects of dynamic loadings on cyclic behavior and cyclic deformation capacity of the dampers had not been made clear. In this paper, dynamic loading tests of full-scale U-shaped steel dampers were carried out to verify these effects. The major findings obtained from the tests are: (1) cyclic deformation capacity of various-sized U-shaped steel dampers can be evaluated based on horizontal shear deformation γ calculated from the lateral displacement δ divided by the height of the dampers; (2) in-plane (0-degree) loading is the critical direction for U-shaped steel dampers in the range of horizontal shear deformation γ from 20 to 200% ; (3) the effect of dynamic loading on cyclic behavior and fatigue characteristics is minimal.

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The effects of high temperature on the mechanical properties of high strength concrete (HSC) have been studied experimentally at various temperatures that covered the 20°C and the 100 to 800°C temperature range at 100°C increments. Concrete specimens of HSC were tested under compression at ages about 3, 6 and 12 months. The stress-strain curve of HSC under compression test exhibits brittle properties below 500°C, and ductile properties above 500°C. The compressive strength decreases to about 60-70% of the strength of room temperature at 100°C, increases up to about 80-90% of the strength of the room temperature at 200°C and gradually decreases with further increase of temperature. From these test results (including Ref.9 test results), mathematical expressions of the compressive strength, the strain at compressive strength, the stress-strain relationship and the modulus of elasticity were proposed. The comparatively good correlation between predicted and experimental results indicates the adequacy of the expression of stress-strain relationship.

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