The purpose of the present paper is to establish a simulation method of the behavior of fresh concrete at its mixing, placing, consolidating, etc. As one of the method to estimate the flow and deformation of fresh concrete, a method of visco-plastic finite element analysis is proposed, and some analytical results are shown in this paper. In the analysis, slip resistance force between boundary surface and fresh concrete can be considered, and the dynamic behavior can be analyzed by calculation of the retardation of velocity change. The results of simulations are in good agreement with those calculated by simple theoretical equations about some examples such as flowing in pipe, parallel-plates plastometer, slump test, and the adequacy of the proposed analytical method is confirmed.

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The association of the J-integral estimations which are applied to metal and the indirect method by means of a cohesive force model analysis based on the same J-integral concept was experimentally investigated. As a result, the reasonable agreement was obtained concerning a relation of J-integral value and deflection among the experimental method by Beglay-Landes, the semi-analytical method using the Rices formula and the present method basad on an analysis of damage of the fracture process zone.

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Experiments regarding impact fracture of floor finish ceramic tile applications have been conducted using a freely falling steel ball. Measurements of coefficient of rebound and time of contact concerning the impact of the steel ball on ceramic tiles in place were made in these experiments. The values investigated for basic parameters were : impact velocity, 0.44 to 9.90 m/sec ; weight and diameter of steel ball, 400 g and 47.6 mm ; type of ceramic tile, porcelain, stoneware, and earthenware ; and application method of ceramic tile, thin-bed method and thick-bed method. It was found that the impact fracture behavior of the ceramic tiles could be explained in terms of decrement of coefficient of rebound which was influenced by an impact fracture index. Perforation fracture of ceramic tiles tended to occur with the thin-bed method. In contrast, there was a tendency for yield fracture of the applied mortar to occur with the thick-bed method because of the weaker strength mortar used in this method. These fractures could be pinpointed as the inflection point of the time of contact. To improve impact resistance of flooring ceramic tile, application materials and application methods having greater values of (1) elastic moduli of ceramic tile and applied mortar, (2) ceramic tile thickness, and (3) shearing bond strength between ceramic tile and applied mortar should be chosen.

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The purpose of this investigation is to examine the S-N diagram and the fatigue process, and the fracture toughness of cement mortar specimens under repeated impact bending load. Here, S is impact load level and N is numbers of repeated stroke. This investigation is divided into three tests. The S-N diagram of cement mortar specimens was clarified by the first test which we struke the falling ball with stell on the center of simple beams (shape of beam = 4×4×16cm, span = 15cm) to obtain impact fatigue life data. The second test is the fatigue process test which was performed by the same method as the first test to obtain the relation between numbers of repeated stroke and impact flexural strain, and residual strain as well. The third test is the fracture mechanics test which was performed on two simple beams with notch and without notch to clarify the crack propagation process under repeated impact bending load and to expect impact fatigue life of cement mortar specimens. The main results obtained by this investigation are summarized as follows. (1) From the first test, relations between S and N can be showen by two straight lines on the S-N diagram. When S is larger than an intersecting point which is named the specific impact load level S_0, the impact breakage is the predominant behavior on the S-N diaram. When S is smallar than S_0, impact damage is very little, then the fatigue process ia observed. Here, S_0 is about 55 % of impact bending strength. (2) In the case of S>S_0, the crack propagation under repeated impact bending load is in proportion to S and the propagation process of impact flexural strain and residual strain change remarkably. Therefore, the fatigue process under repeated impact bending load can be estimated by the crack propagation and impact flexural strain and residual strain. (3) When the linier fracture mechnics applies to cement mortar specimens under repeated impact bending load, the fatigue life of specimens, that is, the crack propagation curve and numbers of repeated stroke into fracture, is estimated by statical stress intensity factor K and physical constant c and m. Here, the values of c and m can be obtained by the experimental results.

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A two-dimensional finite element (FE) formulation for turbulent flow is developed using isoparametric elements and applied to the time-dependent wind flow around square cylinders. Among several turbulent models that have been proposed, the Large Eddy Simulation (LES) is adopted with a top-hat filter to separate a scale of motion. It is concerned here how to introduce the concept of the eddy viscosity in the FE scheme. The velocity and pressure field around square cylinders are presented.

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The purpose of this study is to establish a rational aseismic design method, through the experimental and analytical research, applicable to the large turbine building of a thermal power plant, which accomodates many important equipment like steam turbines, generators and incorporates aseismic elements composed of k-type braced frame. Since the turbine building has large void spaces and openings in floors for turbines, generators and etc., the floor cannot be treated as a rigid element, hence plane frames, under the effects of adjacent frames, behave with respective difference during earthquakes. And there is additional limitation on arrangement and number of bracings. Consequently it becomes very important in terms of seismic capacity beyond elastic range to take into account both three-dimensional effect and inelastic behavior including post-buckling phenomena of bracing during severe earthquakes. The method was developed for the dynamic response analysis of the whole structure, taking into account both three-dimensional effect and inelastic characteristics, in which plane braced frames were connected to each other by springs representing floor component. Using the dynamic analysis system originated, we carried out inelastic dynamic response analysis under severe earthquakes, and confirmed high seismic capacity of the turbine buildings.

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A Kind of condition against the Saint-Venant's Principle has been proved by means of the continued fraction method which is a kind of new way of analysis. An example shows that the strain or deformation will be able to present at even infinite far point by a self-equlibrated system of forces.

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On the basis of this study, the following conclusions may be drawn concerning steel square tubular column bases embedded in concrete footings. (1) In the case without any reinforcements, when the embedment length is long enough, the stiffness of the column base connection is equal to about half of that of steel column fixed at the top of the footing. (2) In calculating the displacement of the column, the depth of the apparent fixed end is 1 D to 1.5 D. (D : Depth) (3) The maximum concrete bearing strain near the embedded square hollow structural sections under the horizontal loads occurs at the both corners of the sections. However, the bearing condition is improved by filling with concrete. (4) In predicting the strength of the embedded square hollow sections when governed by concrete failure, the effective width coefficient should be taken as 3.0√<t/W> (t : thickness, W : width) to give an equivalent width coefficient. This coefficient is should be taken as 0.9 when the hollow sections are filled with concrete. (5) The ratio of the resistance moment at the base plate to the maximum moment of the column beneath the top of the footing is influenced by the embedment length. In the case of the embedment length longer than twice the tubular depth, the ratio is comparatively small.

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Earthquake responses of sandy soil layers under the assumption of pore water pressure in drained condition are presented. Detailed overall consideration for various factors and effects induced by liquefaction are described by parametrical survey. The effective stress dynamic analysis by solving the discrete mass system with nonlinear hysteretic behavior is used. The following important factors for liquefaction and seismic response of sandy soil layers are considered by analysis, i.e. 1. Three types of earthquake ground motion records 2. Hysteretic properties of soils 3. Progressive developement of pore water pressure 4. Permeability of sand 5. Movement of water-table 6. Internal damping effect 7. Variation of soil rigidity in depth 8. Energy dissipation to bedrock. Time hystory and hysteretic responses in detail and maximum responses in each depth of soil layers are given for evaluation of some effects of pre-mentioned factors on liquefaction. Over-all discussions for liquefaction potential and prediction are prepared and some remarkable suggestions to engineering purpose for design are proposed.

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This paper describes results of scaled model test for bearing capacity of nodular cylinder pile as compared to non-nodular cylinder pile. Model piles on the scale of one-fifth are tested for penetration in sand pressured by the vertical and horizontal stresses. The movement of sand around the pile is observed by X-ray photograph. The test results are summarized as follows. (1) The lowest nodule part of a pile works in the same way as the pile tip. Other nodule parts also work similarly to the pile tip in small settlement. But in large settlement, a cylindric slip surface with diameter larger than the nodule is formed around the pile. (2) The point bearing capacity of a nodular pile is 75 percent of the capacity of a non-nodular pile. (3) The shaft capacity of a nodular pile is about 2.5 times as much as that of a non-nodular pile. The shaft capacity of a nodular pile is about twice as much as shear resistance of cylindric slip surface.

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