Low tensile rigidity of continuous fiber reinforcing materials (CFRM) must influence the shear capacity of concrete beams with CFRM. In order to study the shear resisting mechanism, deflections along a shear crack and strains of reinforcement were experimentally examined in detail. At first, the influence of low tensile rigidity of CFRM on the concrete contribution for shear capacity was evaluated using concrete beams without stirrups. Then introducing a deflection model along a dominant shear crack strain distribution in stirrups was determined and the stirrup contribution to shear capacity was quantitatively evaluated taking account of stiffness and with/without yielding.

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Authors derive an equation, which gives a yield value of fresh concrete from a slump flow value, on the supposition that the flow of fresh concrete shows a Bingham Plastic.
Making experiments of slump flow tests and ball drag tests, a yield value of fresh concrete obtained from a slump flow test shows similar value from a ball drag test.
Consequently, a yield value of fresh concrete is able to be obtained by a slump flow value.

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In this study, the macrocell induced corrosion behavior of steel bars embedded in concrete members was experimentally and analytically investigated. The macrocell and macrocell current densities and potentials were then evaluated. The comparisons between the type of joint and the permeations of oxygen through the joint were investigated. And, the comparisons between the proportions of concrete and the permeations of oxygen through the joint were investigated. Their influences on corrosion were studied. Lastly, the macrocell corrosion rate near the joint was simulated. Results showed that the permeation through the joint and resistance between new and old members played important roles in macrocell corrosion behavior.

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The Great Hanshin Earthquake caused tremendous damage to the RC piers on the Hanshin Expressway's Kobe Route, and those piers needed retrofit or reconstruction. To investigate the effect of ductility increase on those piers, four types of reinforcing methods (Steel plate jacketing, Reinforced concrete jacketing, a combination of steel plate jacketing and reinforced concrete jacketing and reconstruction of reinforced concrete piers) were tested, and RC non-linear analyse were conducted. All the results from both tests and analyses were showed that considerable increase of ductility was achieved and satisfied analysis values derived from Restoration Specifations. It was also found that post-installed anchors do not give any detrimental effect to the ductility of the piers.

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It was investigated in this paper that the excess paste theory, which is one of the conventional theories for mix design of concrete, was able to apply the evaluation of fluidty of mortar in order to establish the theoretical mix design method of concrete. It was experimentally verified that flow value of mortar was uniformly evaluated by excess paste ratio δ/d, in which δ was the average thickness of excess paste, and d was the diameter of fine aggregate particle, on condition that shape, particle size distribution and unit volume of fine aggregate were varied.

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A new evaluation method for the probability of failure of a structural system based on reliability theory is proposed. From the numerical examples, it is demonstrated that this method possesses high accuracy and simplicity. And the safety of RC bridge pier against earthquake is evaluated on the basis of the proposed method. In this analysis, three limit states-flexural capacity, shear capacity and ductility-are taken into consideration. It is shown that shear/flexural capacity ratio and ground condition are very important factors in order to evaluate the seismic performance of RC bridge pier. Finally, new concept of seismic design for RC bridge pier based on reliability theory is proposed.

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Fresh property of mortar and concrete with various powder are analyzed by the water layer model which involves flocculation of powder. It was examined the relation of water layer thickness which is calculated using water layer model from the water powder volume ratio to flow and V-funnel value by mortar and concrete.
The results indicated that fresh property of mortar and concrete and a water layer thickness correspond directly, a water powder volume ratio of concrete is calculated from the size distribution of powder, and the water layer model is effective in designing the mix proportion of self-compacting concrete.

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It is important to calculate quantity of water in designing the mix proportion of self-compacting concrete precisely. From such a point of view, this study deals with what kind of physical properties of powder influence paste flow. The water layer model which involves flocculation of powder is proposed in this study. It was examined the relation of water layer thickness which is calculated using water layer model from the water powder volume ratio to paste flow.
The results indicated that paste flow and water layer thickness correspond directly, and a water powder volume ratio of paste is calculated from the size distribution of powder.

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The proposed autogenous and drying shrinkage model is based on micro-mechanical behavior of water in pore structure in concrete. In our modeling, it is assumed that the shrinkage of concrete due to self desiccation, known as autogenous shrinkage, would be derived from the surface tension force of capillary water across curved meniscus, as well as drying shrinkage processes. The material properties of concrete are evaluated considering the inter-relationship of hydration, moisture transport and pore-structure development processes based upon fundamental physical material models. By implementing the shrinkage model to this system, the volumetric change of concrete can be predicted for different water to cement ratio, curing and mix proportions satisfactorily.

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In the structural design of continuously reinforced concrete pavement (CRCP), thermal stresses should be properly taken into account. In this study, thermal strains and temperatures in a concrete slab were measured on a test section of CRCP. Measured strains were divided into average, curling and nonlinear components and each component was examined. It was found that the curling component is predominant, in trems of transverse stress which is important in the stuructural design. However, the maximum of the thermal stress is reduced by 25% due to the effect of the nonlinear component. Based on the results, a procedure for eatimating the thermal stress in CRCP was proposed and verfied by the measured data.

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In the preceding paper, we already discussed that the main problem which make the modified asphalt concrete difficult to rejuvenate is caused by the thermal decomposition of the conventional modifier.
To remove this undesirable phenomenon, we studied three different types of modifiers, i. e., SBS, SBS with radical scavenger and hydrogenated SBS. And we found that hydrogenated SBS is the most suitable asphalt modifier among them for the repeated recycling.

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We reported a method of the neural network performance modeling using a pavement design equation. In that case, pavement data, which were measured for several consecutive years at a pavement section, were applied to modeling. In this study, we examined a method of the neural network performance modeling applying annual pavement data measured at a few pavement sections.

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