Waste concrete fine powder that is residue after aggregates recycling of demolished concrete is disposed as a low material of value. And Waste sulfuric acid is the waste discharged in large quantities by industrial activity. In this paper, we developed the handling process of waste concrete fine powder using waste sulfuric acid. By using this handling process, plaster of Paris with high purity was separable from waste concrete fine powder. Then, waste sulfuric acid was able to carry out neutralization processing.

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Recycling of construction and demolition waste, especially concrete recycling has become more important for the establishment of sustainable society due to the depletion of natural resources and the lack of final disposal area. However, recycled aggregate made from demolished concrete could bring about several problems, one of which is the various impurities contained in the recycled aggregate, i.e. plastic, wood, wastepaper, tile, ceramics, brick, etc. that may cause the performance degradation of concrete. Therefore, it is significantly important to determine the influences of some impurities on concrete performance because perfect removal of all impurities is impossible. Though the upper limits of impurities contents in the recycled aggregate was enacted as JIS A 5021 and 5022 (Recycled aggregate for concrete-class H and M), those for metal impurities have not been specified yet. This paper evaluated the properties of concrete containing two types of metal impurities, i.e. aluminum and iron. The effects of those on concrete performance were tested through various experiments. As the result, it was found that aluminum contained in recycled aggregate adversely affects both mechanical properties and durability even with very low content. This paper also suggests a simple inspection method to reduce the risk of the aluminum impurity in recycled aggregate.

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It is important to know the seismic resistance capacity of ceramic tiles commonly used as external coverings of buildings. This is because fall-off of tiles during earthquakes poses a considerable danger to pedestrians. However, few dynamic seismic tests have been conducted on non-structural members such as ceramic tiles. In this study, a three-dimensional shaking table test was conducted in order to determine the seismic resistance capacity of wet construction methods for fixing ceramic tiles. This paper presents the test results of an earthquake response evaluation of a reinforced concrete wall subjected to horizontal uni-axial vibration. It is concluded that ceramic tiles applied by the standard method gradually fall off when the applied rotation angle increases. The tiling method utilizing a three-dimensional fabric and anchor pins maintains its adherence to the concrete substrate during the final input earthquake motion.

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We devised backing of the U type shape made by the ceramics which added CaF2 and Fe2O3 in 2MgO•2Al2O3•5SiO2 5% from 2 as backing of the welding joining of the reinforcing concrete. This backing has the good point that confirmation of the viewing of the weld is possible by removing backing after welding. As a result of having carried out a tensile test, a repetitive test, a bending test in the welding joining that we used backing made by ceramics for, that we satisfied an all judgment standard was shown.

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Two test methods for evaluating wind resistance of mechanically anchored waterproofing membranes were developed on the basis of the new findings, which was obtained through the observations in some typhoons, that horizontal force is induced as well as uplift force at fixing portions in membranes. Two apparatuses with different mechanism to reproduce uplift force and horizontal force were prototypically made. As for the first apparatus, a membrane was ballooned up by two air bags inserted between a membrane and a substrate and then inflated by high-pressure gas. For the second one, uplift force was applied through tensile test machine and horizontal force was directly applied through horizontal loading mechanism. Some tests of mechanically anchored waterproofing membranes were carried out for applying both apparatuses, and advantages and disadvantages of those test methods were discussed.

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This study provides investigation results and discussion on axial forces and lateral forces applied to waterproofing membrane and fasteners, mainly purposed to demonstrate lateral forces affecting the mechanically-anchored waterproofing membrane system when subjected to strong winds during a typhoon on the island of Miyako in 2009. The polyvinyl chloride waterproofing membrane reinforced with polyester fiber was attached to the flat roof without parapets and the forces of fastener were measured by 6 component force transducer. It was considered that the lateral force affecting fastener of waterproofing membrane occurs by the difference between the windward and leeward at the fastener. Average lateral force of fastener was same value as its vertical force and a maximum lateral force was 1.7 times of it. The tension which pulled PVC sheet up was approximately 4 times as much as the wind pressure at the height of eaves of the building. It is presumed that such lateral forces and axial forces causes waterproof membrane damage that ripped the sheet during a typhoon.

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In this paper, the influence of the external factors on the amount of hexavalent chromium Cr(VI) released from the concrete waste and the adsorption/reduction action caused by the surround soil, was investigated. The following results were obtained.
1. Serial batch test using mildly nitric acid solution is expected to be able to assess available amount for leaching under the general environment.
2. In case of the carbonation sample, the dissolution continued under the soaking condition, after the 91 days.
3. Blast-furnace slag fine aggregate and the powder reduced Cr(VI).
4. Volcanic cohesive soil and organic soil have the capacity of absorption/reduction.

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This paper describes analytical results by a boundary element method on stress singular conditions at the interface between the concrete bodies and cemeticious adhesive mortar with ceramic tiles. The interfacial stresses during differential movements between concrete and ceramic tiles were examined in case that both defects and no ones were held in the interfaces. A general stress function is also presented by two singularity parameters to predict normal and shear stresses near the stress singular points by a fracture mechanical method. By the results, the predicted method for critical conditions of the defects in the interface was presented. Furthermore, the mixed-modes of the interfacial fracture were clarified.

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Applying an earthquake response evaluation method of buildings proposed by the authors, which uses the equivalent SDOF system responses and the higher mode responses obtained from both the time history earthquake response analysis and the modal adaptive pushover (MAP) analysis, the earthquake response characteristics of RC buildings with setback were investigated. Analyzed were four twelve-story RC buildings with different setback layouts. The results indicate that translation responses are more dominant than torsional responses for buildings with setback in the upper story, while torsional responses tend to be prominent for buildings with setback in the lower story. It is also clarified that torsional responses are extremely increased at a story right under the setback story, and the torsional responses include a lot of higher mode components.

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In this paper, wave propagation in an irregular ground due to incident surface waves is formulated by combining the 2.5 dimensional thin layered element method and the 2.5 dimensional finite element method. From this study, the following conclusions are made: 1. From the analysis of the microtremor wave field due to various incident surface (Rayleigh and Love) waves, it has pointed out that H/V spectra and dispersion curves are influenced by both body and surface waves generated from the irregularity (slope in this study) of the ground. 2. It is also confirmed that effect of interference between the incident wave and waves generated from the slope changes depending on the angle of incidence. 3. A comparison with the observation data has shown that the 2.5-D analysis can give good results when compared to the 1-D or 2-D analysis. 4. Estimated phase velocities from observation data show a tendency of accuracy degradation in the vicinity of the H/V spectral peak.

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The purpose of this paper is to describe the derivative process of the theoretical solutions of the equations of orthotropic elastic rectangular beams with uniformly distributed loads. On the process of inducing, it indicates the exact physical meaning in practical expressions, and in addition reveals the cause of the confusion of shear deformation coefficients in Timoshenko's beam theory. In order to comprehend the deformation and in-plane stress state of the beam, the beam theory has been extended, which incorporates Young's modulus E_y , Shear modulus G_xy and Poisson's ratio v_xy in turn. Then, we summarize the results as the non-dimensional expressions, indicating the closed-form solution of the equations under the given conditions. Also, some examples are shown under different boundary conditions.

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The authors carried out “tensile and compressive load tests in the laboratory and fields”, “simulation analysis load-deflection behavior” on cast-in-place under-reamed piles. We obtained below conclusions from the results of these tests and analysis.
1. The (pu)- value decreases with increasing the ratio (D/d). 2. The shape of (p-S)relation curve changes according to the value of (D/d),θ,etc., but [(p/pu)-(S/D)]curve is a fixed curve regardless of these value. [P : load-carrying capacity of under-reamed bulb, p : P/A(A:π (D²-d²)/4 where D and d are under-reamed and stem diameter respectively), S : displacement of under-reamed bulb, θ : tapered angle of the bulb, pu : p-value where (S) reaching to 10% of under-reamed diameter]

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In Niigata-Ken Chuetsuoki Earthquake (July 16, 2007), water storage tanks suffered considerable damage. These tanks belong to C-class facilities. Types of damage were versatile. Some suffered buckling of tank walls such as diamond pattern and elephant-foot bulge type of buckling. Some suffered breaking and permanent elongation on anchor bolts circumferencially distributed at the bottom of tanks, accompanied with uplift of bottom plates.
The seismic input recorded at the site was tremendously large compared with that applied at the design stage, however, most of damaged tanks barely escaped from the fatal damage of leakage of water.
In this paper, real behaviors of tanks are estimated referring to ‘Design Recommendation for Storage Tanks and Their Supports’ published by Architectural Institute of Japan in 2010.

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For the examination of building collapse, it is required to analyze the building performance using the pertinent analytical model for the columns. The residual axial load capacity of the column after shear compression failure in the bending hinge zone is different from the capacity of the columns after shear tension failure. This paper investigates the analytical model for the column experienced failure in the bending hinge zone based on the M-N surface contraction. The reduction rate was obtained as a function of the maximum deformation, shear margin ratio, strength of longitudinal and transverse reinforcement, using the regression analysis of experimental results. The tested results are explained by this formula with good agreement.

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Results of five series of seismic tests on reinforced concrete interior beam-column joint subassemblages are reported. The effects of design parameters of joints including amount of longitudinal reinforcement, ratio of column to beam moment capacity and ratio of depth of the column to depth of the beam are investigated. Maximum story shear of some specimens are smaller than the story shear calculated by the flexural strength of the beam or the column if the flexural strength of the column is equal or near to that of the beam, although the joints have enough margin for nominal joint shear capacity.

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First, this paper shows shaking table test and time domain analysis results for z-type steel frames with an NC brace and normal one subjected to a sine wave input. One sided deformation in frames with an NC brace is observed from time domain analyses as well as shaking table tests. Next, the paper also shows a lot of time domain analysis results for above frames subjected to recorded earthquakes and artificial earthquakes compatible with the design spectrum. Not only one sided deformation but also the effectiveness of methods to predict energy absorption of NC braces are observed from analysis results.

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A number of school gymnasia in Japan built in the 1970s in Japan have exhibited or lead one to foresee insufficient seismic performance, and seismic retrofits on them are still underway throughout the country. However, current assessment practices do not take into account the vertical vibration excitation peculiar to raised roofs, which heavily impacts the collapse of non-structural elements, such as ceiling components or lighting equipment. Energy dissipating retrofits are better suited than common strength-based retrofits to help reduce such excited vibration, however, optimum design and evaluation methods remain unclear. This paper looks at the typical school gymnasia in Japan, and investigates retrofit design using elasto-plastic or viscous dampers, discussing its effects on roof response reduction and practical response estimation methods.

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Non intersection-type beam-to-column connection of steel moment resisting frame is proposed. This connection is composed of rectangular hollow section column, wide flange section beam and rectangular hollow section bracket. In this connection, moment is transmitted from beam to column by torsion moment of bracket. In order to evaluate the structural performances of non intersection type beam-to-column connection, a series of experimental and analytical study is carried out. From both of experimental and analytical results, it is clarified that non intersection type connection behave stable even in the plastic region.

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In the field of energy based seismic design, the structural performance of steel structures is determined by the energy dissipation capacity, which depends greatly on the plastic deformation capacity of the structural components that form the whole system. The plastic strain capacity of the structural steel is one of the primary factors that determine the components' plastic deformation capacity. Most of the cyclic loadings employed in the structural steel tests are the recommended standard (typically incremental or constant amplitude) loading protocols, which is insufficient to study the deformation capacity under random loadings such as earthquake effects. This paper focuses on the evaluation of the plastic strain capacity of structural steel under various axial strain histories till ductile fracture. A series of element specimens made of SS400 and SN400 steel were tested under diverse cyclic axial strain loadings. The deformation capacity of the structural steel under cyclic axial loading till fracture was evaluated by studying the experimental strain capacity/energy dissipation capacity of the skeleton curve and the Bauschinger part. The error range of this method was proved smaller than that of the Miner's rules.

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This paper addresses the derivation of collapse load of beam flange to circular tube column connections with exterior diaphragm based on plastic analysis. In order to verify the validity of the derived collapse load, component tests of the connections were conducted. Major findings obtained from tests are summarized as follows: (1) the yield strength obtained from the tests was about 80 to 90% of the calculated collapse loads, (2) the local deformation of the circular tube column that corresponds to the calculated collapse load is small enough for the yield strength, (3) the derived collapse load formula which is considering the shape of the connections correlated well with the test results, and captured the trend in a reasonable manner, (4) the maximum strength obtained from the tests was about 110 to 120% of the calculated maximum loads.

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The purpose of this study is to clarify stress transferring mechanism and strength evaluation of the joint connected steel member with reinforced concrete member using anchor bolt based on stress transfer from steel member and reinforced concrete member. To clarify stress transferring mechanism of the joint connected steel member with reinforced concrete member using anchor bolt, seven T-shaped assemblages were tested under monotonic loading. From the test results, it was shown that stress transfer from steel member to reinforced concrete member in the joint could be mobilized by transverse reinforcements arranged intensively around anchor bolt. Based on the arch mechanism and the truss mechanism, a method capable of estimating the ultimate strength of the joint was proposed. The predictions were shown to be in good agreement with the test results. In addition, it was shown that this proposed strength model could apply to the ultimate strength evaluation of the exterior beam-column joint using mechanical anchorages on the reinforced concrete structure.

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Theoretical studies are presented on the structural behavior of a hybrid beam-column which is composed of several structural elements, arranged non-symmetrically. A new concept “uniform compression” is introduced as the substitution for “concentric loading”, and the alternative definition of tangent modulus load is also introduced. Steel sandwich beam-columns composed of different steel specifications and steel-concrete composite beam-columns with non symmetric steel shapes, subjected to eccentric compressions, are investigated. Safety side estimation of bending strength is obtained by substituting reduced symmetrical steel sections. Numerical simulations shows a good agreement with experimental results.

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