Structural health monitoring (SHM) of large-scale structures on a continuous or real-time basis has been becoming possible in the last years due to the great advances in sensing, information and communication and computational technologies, and intense R&D and promotion activities have been performed at home and abroad. Within last two years, the 328 sub-committee has conducted a systematic investigation on the recent R&D achievements and applications of SHM technologies by focusing on the three categories of sensing, processing and evaluation and diagnosis techniques. Moreover, based on these results, the SHM design methods and applicability for different kinds of concrete structures have been studied and discussed.

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In this paper, we propose an uniaxial tensile strength test method as the test method that can be useful in design with simple and appropriate precision for quantitative evaluation of tensile characteristics of chemical prestressed concrete members. This test method uses the members which shortened length by restricting expansive strains with the restriction appliance that installed restriction end plate at both ends of restriction rod in order to make the handling simple and easy. We checked precision of test method and characteristics, and as a result we confirmed the propriety of test method.

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The method of evaluation of inspection on concrete surface and detailed inspection is presented for three purposes as follows. The first objective is quantification of steel corrosion grades and conditions of concrete surface, the second one is prediction of steel corrosion grades and conditions of concrete surface due to cover, carbonation depth and chloride content on steel surface, and the third one is revision of prediction results with concrete surface conditions. This thesis shows prediction method of concrete surface condition based on prediction of steel corrosion grade with use of correlation model between corrosion grades and concrete surface conditions, and revision method of prediction with use of inspection result of concrete surface by adjusting carbonation speed factor, cover depth, chloride ion content on concrete surface and chloride ion diffusion coefficient for coordination of prediction result to inspection result.

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This paper focuses on behaviors of moisture dispersed in nano-macro scale pores under various temperature and relative humidity conditions. The authors formulated an equilibrium relationship between liquid and vapor phases and a moisture flux driven by pore pressure, vapor pressure and temperature gradients. In addition, liquid and interlayer water were measured separately by ethanol in order to reveal each temperature sensitivity in saturation-humidity paths. Based on the experiments, a modified hysteresis model for moisture isotherm was proposed. Verifications with experimental data showed that the proposed method can simulate moisture behaviors under various temperature conditions.

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When pavement structures like roads and runways are under simultaneous actions of vertical load due to wheel loading and horizontal load due to brake loading, analysis is normally performed considering these loads as uniformly distributed. However, since center of gravity of the vehicle is above the surface of the pavement, starting or stopping of the vehicle will result in not only horizontal load but also moment load due to inertia force causing vertical and horizontal loads to be trapezoidally distributed. This paper presents solutions for trapezoidally distributed loads. Results for rectangular load show ε_x and ε_z at the bottom and top of surface and subgrade layers, respectively, are over 60% higher than for triangular load.

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The beam loading experiments in the several loading and structural conditions were conducted to evaluate structural performance of reactive powder concrete (RPC) with 200N/mm² compressive strength and 35N/mm² flexural strength, which is one of ultra high performance fiber-reinforced concrete. Based on experimental results and SETRA/AFGC recommendation, a design equation of shear capacity was simplified and improved. Fiber analyses considering a size effect of flexural strength of RPC were carried out and compared with experimental results. It was verified that this fiber modeling analysis method for RPC could evaluate the flexural behavior of the RPC beam. And this analytical method is useful for a practical design for the RPC structures.

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A multi-directional fixed crack model based on the active crack concept which enables to simulate real crack propagations on concrete was created for reactive powder concrete (RPC) with 200N/mm² compressive strength and 35N/mm² flexural strength, which is one of ultra high performance fiber-reinforced concrete. Numerical implementations of the newly developed non-linear finite element analysis applying the crack propagation model were compared with the loading experiments of RPC beam. It was clarified that this FEM model could evaluate the flexure and shear behavior of RPC beams. Through the numerical simulations varying the factors of the effective depth, the shear span ratio and the tensile reinforcement ratio, the revised shear capacity equation was investigated in comparison with the experimental results.

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The seismic design have been revised to give so high seismic requirement after Hanshin-Awagi earthquake disaster. Usually we design the reinforced concrete viaduct for Railway to have high deformation capacity. So we carried out reversal cyclic loading test using reinforced concrete model column reinforced by inside round hoop bar to give so high seismic requirement. This paper mainly presents the deformation properties and damage by the results of reversal cyclic loading test of this model column.

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This paper proposes an estimating method of the pressure loss of self-compacting concrete passing through the gaps between reinforcing bars, and proposed two types of easy dynamic mechanism models, the theory of virtual minute tube model and friction between solid particles. Suitability of these models were investigated by several experiments accepted the theory of rheology. Results of these experiments, they were made known, pressure loss could be estimated suitably using unit absolute volume ratio of coarse aggregate and the gap size between reinforcing bars, and in the case of theory of virtual minute tube model, pressure loss could be estimated suitably using the yield stress of mortar, length and radius of virtual minute tube.

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In the designing method for footings, the effect of the shear reinforcement of stirrups has not been considered, because the shear strength of footings with stirrups has not been clarified. In this study, therefore, loading experiments were executed with models of footings with stirrups for pile foundation. Thus, the effect of reinforcement of stirrups was clarified. Moreover, a method of integrating the shear strength of deep beams was proposed as an evaluation method for the shear strength of footings. It was clarified that the shear strength of footings with stirrups was appropriately evaluated by the proposed method.

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Recently, composite prestressed concrete (PC) bridge girders, which web member is made by various materials, have been developed. In this study, new composite PC structural members using Ultra High Strength Fiber Reinforced Concrete (UFC) as a web truss member are examined. UFC has high compressive strength around 200MPa, high ductility, and high durability. Due to its predominant mechanical properties, UFC can be applied to the web member of composite PC bridge girders and the self-weight of girders can be significantly reduced. The aim of this research is to investigate the mechanical properties of composite PC members using UFC truss and to evaluate the effect of weight reduction. Then, composite PC beams are designed and experiments and FEM analyses are carried out. In addition, the extent of weight reduction of a web member is examined.

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The impact-echo method has been applied to nondestructive evaluation for concrete structures. Taking out resonant frequencies responsible for the locations of reflectors in the frequency spectra, identification of reflectors is performed. Stack imaging of spectral amplitudes based on impact-echo (SIBIE) is developed, in order to improve the impact-echo and visually identify the locations of reflectors. In the present paper, two-dimensional dynamic BEM analysis is performed to confirm an applicability of SIBIE. At the peak frequencies in the spectra, distributions of the stress and deformation are clarified.

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