Raising the mixing temperature or the curing temperature of concrete made with portland cement improves the strength at early ages, but invariably causes a reduction in the long age strength. This paper describes tests in which the curing temperature of fresh concrete in early stage, was controled. In order to improve the development of strength hot-mixed concrete. In conclusion, the long age strength of hotmixed conerete is depend on the temperature of dormant period, ie. when the temperature is controled to be low, the strength shows higher values than other conditions.

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This study evaluated aseismic strength, its deviation and threat to occupants' life of several dwelling types common in Turkey as a function of seismic intensity. A result of field survey on building damage and site geology within a small town was reexamined first. Besides, based upon village atatistical data, dislribution of dwelling damage and haman life loss at the 7 earthquakes since 1966 are compared with seismic intensity, considering local structural types. Adobe or rubble stone masonry type dominant in the eastern Turkey is found the weakest, even weaker than Structure A in MSK scale, then poor wooden, brick masonry, reinforced concrete, fine wooden follow in this order. The best type, fine wooden, is comparable to Structure C but is less earthquake resistant than a common timber framed house in Japan. Several factors such as earthquake fire and human behavioral performance were also found to be influential on risk of casualty and its content.

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When the mathematical non-linear programming technique is applied to the optimal design of multi-story reinforced concrete frames, the structural analysis must be repeated many times. Consequently, the computational time to obtain the optimum design is increased. It is proposed herein to overcome this difficulty by predicting the initial design values that are nearly equal to the optimum design values. The process to obtain the initial design values is composed of the theorical and numerical procedure. In the theorical procedure, the reinforced concrete frame is partitioned into the story-subframe and the assemblized story-subframes. The preliminary design values in the theorical procedure are obtained by solving the minimum weight design problem with the relative story displacement constraints. The initial design values are obtained by modifying those preliminary design values in an iterative sequential process in which the numerical procedure is applied. The minimum weight design of three types of reinforced concrete frames that are subjected to static loads are carried out by the proposed method, and the results are discussed.

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This study is another challenge to the analysis of surface crack problem proposed by Benthem, and intends to make f formulations by using the so called spherical coordinates Boussinesq's function, which is widely used in the analysis of the three dimensional problem of elastic body. This method has enabled me to obtain, in the explicit form, the predominant solution of stress in the vicinity of crack front with infinite depth. It has also enabled me to make clear its correspondence to the solution obtained by Sih and others that is shown by the cylindrical coordinates.

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In this paper, based on E. Reissner's theory for the rectangular plate with three built-in edges and a free edge a system of series solution is obtained and this and its equivalent of the classic solution are compared respecting the influence of their different setting of boundary conditions for the free edge on the preceding results including the transverse shear effect which is a major consideration in this case of structure but seems to have insufficiently been investigated. Sets of data thus provided are further used here in examining shear stresses in actual tested reinforced concrete slab models that have undergone failure of shear type.

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The object of this paper is to formurate for the dynamic behavior of an elastic shell due to viscous flow surrounding it. The motion of viscous fluids is governed by the Navier-Stokes equation and the continuous equation of pressure expression. Analysis of the dynamic behavior of an elastic shell due to viscous flows is treated as viscous fluid-elastic shell interaction through the interface boundary on which continuity of mechanical action is required. The stresses acting on the elastic shell are pressure and viscous stresses. Especially, the terms of rate-of-deformation tensor in viscous stresses on the interface boundary are expressed by velocity components of an elastic shell in our formulation. By our formulation, analysis of the dynamic behavior of an elastic shell due to viscous flows is possible. The flow patterns around an elastic shell are made clear. For the numerical solution procedure of our coupled problem, finite element formulations based on the weighted residual method are achieved. Appling our methodology to the viscous fluid-elastic cylindrical shell interaction problem as a simple one, we obtain numerically some flow patterns around a circular cylindrical shell structure and the dynamic behavior of it.

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The test specimens were cantilevers with a constant axial force, which were deformed by actuators in two horizontal directions. The adopted hysteresis was circular displacements. The columns were analyzed by the non-linear Finite Element Method, which could deal with both three-dimensional condition and repeated reversal loading. The analyses were executed for two cycles at a constant displacement by input of forced displacements for loads as were done in the experiment. When analyzing a column under severe loading, such as hysteretic loops, the analysis becomes very severe because the direction of loads changes every moment. Consequently this analysis was aimed mainly at the qualitative investigation of the column. Obtained results are ; (1) The following features observed in the experiment are traced by the analysis (a) The hysteretic loop of shear forces is almost a circle. (b) The vector of shear forces precedes that of displacements in an angle. (2) The shear force-story deflection relation obtained by the experiment is traced. But the area surrounded by the hysteretic loop is small comparatively. (3) Strains of longitudinal and lateral reinforcements can be classified according to their location in the column. (4) Obtained axial stresses and strains of concrete show the fundamental feature that the neutral axis rotates in accordance with the loading loop.

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Steel structures have many advantages, but also have the following drawbacks in addition to corrosion : 1) Liability to buckle, 2) lower elastic rigidity and 3) liability to be deteriorated by high-temperature heating. One of the effective measure to improve these drawbacks is the concrete-stiffening of steel structural members. This report has investigated the development of the concrete-filled square steel pipe structures for this purpose, particularly the fire resistance of such columns. Filled concrete is effective in achieving excellent fire resistance in the following two points : (1) When fire resistance is evaluated by the steel pipe temperature, the heat capacity of filled concrete contributes to the suppression of a temperature rise of the steel pipe and (2) When fire resistance is evaluated by the collapse of the member load burden transfer to filled concrete can be expected to cope with the lowering of steel pipe strength due to high-temperature heating in fire. This report clarifies mainly the basic behavior of concrete-filled steel pipe for the latter case. Tests performed include the following two kinds : (1) A heating test under constant load by a loading equipment which has made it possible to detect axial force transfer from the steel pipe to the filled concrete, (2) a heating test under constant load applied on beam-to-column connection, assuming the actual flow of force. Through these tests, information about the transfer characteristics of axial force from the steel pipe to the filled concrete as well as the deformation characteristics and local buckling behavior of steel-pipe columns have been obtained and it has been confirmed that the load bearing capacity against a standard fire heating can be maintained for more than two hours when the applied load is 20% of the axial yield strength of the steel pipe and for more than one hour when the applied load is 40% of the axial strength. The flexural strength of columns after cooling has sufficiently exceeded the design load corresponding to seismic load that may occur after the fire.

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The strength and deformability of defective welded joints may be influenced by many factors such as size and location of defects, type of joints, temperature and so on. Factorial Experiment is, in that case, one of useful means to select what factors are influential or not. Test series I and II are carried out by means of Factorial Experiment, those factors are statistically analysed, and followings can be concluded from this research. (1) Following experimental factors must be considered in the assessment of the influence of weld defect of the quasi-static properties of cross joints. a) The dimensions, especially the width of the specimens. b) The defect location, i. e., whether a weld defect locates at the edge or at the center of the specimen. c) The geometric shape factors, such as rations of defect length to plate width, and of defect height to plate thickness. (2) Following experimental factors can be negligible when cross joints are fractured from weld defect in ductile manner. a) The welding procedure. b) The steel grade. (SM 50 or SM 58) c) The loading condition. (3) The adverse influence of weld defect on the quasi-static properties of welded joints is more pronounced for butt joints than for cross joints.

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This paper aims to clarify analytically elasto-plastic deformation behaviour of multistory reinforced concrete structures with cantilever shear walls subjected to lateral load. Then, the ultimate strength of these structures is expressed theoretically. On the basis of four terms in theoretical equations of the ultimate strength, four parameters which are considered to influence on the elasto-plastic behaviour of these structures are selected, as follows. (1) Ratio of the flexural strength of shear walls to the shear strength of shear walls (Q_<wu1>/Q_<wy1>) (2) Ratio of the shear strength of frame elements to the ultimate strength of structures (Q_<fy1>/Q_<ou1>) (3) Ratio of the yield moment of shear walls to that of adjacent beams (m_<gy1>/M_<my1>) (4) Total stories (n) Regarding to these parameters, elasto-plastic behaviour of structures are analyzed with the analytical method represented in previours paper (1). On the basis of these analytical results, the effect of the above each parameter is clarified on elasto-plastic behaviour of structures.

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