Recently, cement-based cast-in moulds which need no removal after concrete is cast, are being increasingly utilized in building construction in order to achieve labor-saving and work rationalization. Since such forms need to be thin and light for effective use in small-scale construction sites equipped with only small cranes, they must inevitably be made of materials with high bending strength. In this paper, the strength development of cement-based materials with various mix proportions are experimentally examined. It is shown that high-bending-strength cement-based materials can be obtained when low-water-binder-ratio materials with portland cement and granulated blast furnace slag as binders and sulfonated melamine formaldehyde condensate (SMF) as an admixture are steam-cured at high temperatures.

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In this study, the J shaped tube test apparatus was developed to evaluate the rheological characteristic of the high-fluidity concrete by measuring the flow viscosity coefficient and the shear stress yielding value of the concrete. To examine the applicability of this test method, many kinds of the high-fluidity concrete are investigated experimentally.As the result, the flow viscosity coefficient and the shear stress yield value of many kinds of the high-fluidity concrete are obtained, which are found to be similar to the values of the rotary viscometer. And the rheological consideration about these results is carried out, comparing the results of the conventional test method.

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A simplified method to estimate the degree of deterioration of roofing sheets was developed, and discussed using Barcol hardness, crazing area and average crazing width. The elongation rate during tensile test and breaking energy which have been used for estimating the deterioration of the sheets were highly correlated with the value from the combined testing of hardness and surface characteristics. This newly developed method was proven to be an effective nondestructive technique to evaluate the degree of deterioration of the sheets on-site.

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The characteristics of wind-induced internal pressures in a high-rise building have been investigated. Full-scale measurements were taken using absolute pressure meters, which allowed high-resolution measurements. This paper outlines full-scale measurements of wind velocity, wind direction and external and internal pressures on a twenty-nine-story building, commencing in January 1993. It also describes the characteristics of natural wind above the building's penthouse and mean wind-induced internal pressures measured in September 1995 when Typhoon No.12 hit the Kanto area. The internal pressure coefficients obtained from these measurements were about -0.26, and were constant over the building's height. The influence of internal walls and doors on measured mean internal pressure coefficients was found to be insignificant, and roughly the same values were obtained at different locations on the same floor. The mean internal pressure coefficient estimated from the mean wind pressure coefficient obtained from wind tunnel testing was -0.26, which was the same as that obtained from the full-scale measurement. Therefore, it is inferred that the mean wind pressure coefficient obtained from the wind tunnel testing is sufficient for examining average internal pressures.

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A practical solution named PASS, for quickly and easily calculating the settlement process of building with piles in poor soils, is presented. In this method, we introduce the new ideas those are the effective diameter of pile and the effective width among the adjacent of piles. The parametric studies of piled raft with various values (raft soil stiffness ratio, pile spacing, pile length, number of piles, finite layer of soil) are performed. Calculating the settlement of piled-raft using the PASS provides a close approximation to results from analysis using the three-dimensional finite element method for piled-raft.

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In the design of a large span space frame, the first problem to be solved is the problem of stability, the buckling problem, especially for a single layer space frame. For a space frame with a certain configuration, the buckling mode and buckling-load parameter are very sensitive to its original shape (the nodal coordinates of the structure). By adopting nonlinear programming with geometrical nonlinear analysis, the present paper promote a method to find the optimum shape of a space frame with maximum buckling load. A single layer space frame is taken as a numerical example, and the analysis shows that the buckling load parameter increases 18.4%.

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Multispan gable frame structures with suitable beams and braces on the roof show a significant cubic folded plate effect that reduces the displacements and the stress resultants of each gable frame. The basic equations of the structures are derived by introducing an orthotropic plate theory into the roof plate. Then, the gable frame structures with columns and end walls are transformed into a Timoshenko beam on an elastic foundation by imposing restrictions on the displacements of the roof plate. A case where the gable frame structures behave under symmetric displacements with respect to the roof ridge is shown to demonstrate the procedure that gives precise solutions.

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This paper has described tests on the steel connectors embedded into the timber with adhesive. These connectors are threaded steel rods with a hole at center of each rod to transport the adhesive to the end/s of the rods. Tension tests for splices, bending tests for mid-span splices and tension strength of splices for curing period were carried out. From this test result, the fundamental data for the structural design of wooden frames were obtained. The assembly at connection and reasonable structural design can be carried out easily by using this new connection system.

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To achieve ductile behavior of deep RC beams, the effectiveness of diagonal reinforcing methods is widely recognized. But the strength of those beams tends to be underestimated if conventional methods are applied. In this study, the load carrying mechanism of such beams is discussed, and an important role of concrete strut formed between the compression zones on both beam ends is pointed out. The effective strength of the concrete strut is also discussed, and a method based on a strut-tie model for estimating the yield strength of diagonally reinforced deep RC beams is proposed. The method is examined through the comparison between the predicted strength and test results, and then, the method is simplified for practical use. The practical design formula proposed in this paper gives 10 to 30% higher values than those obtained from the conventional method assuming a steel truss composed of main reinforcing bars crossing at the center of the beam.

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After the Hyogoken Nambu Earthquake, January 17, 1995 and the Northridge Earthquake, January 17, 1994, fracture behavior was observed in many steel buildings at their welded connections between beams and columns, structural members and other structural components. In earthquake-resistant design criteria, of buildings, plastic deformations are permitted to absorb the seismic energy, while fractures are unacceptable. Therefore the response properties of a frame which undergoes fracture type collapse behavior have not been investigated. It is necessary to investigate the response properties in order to evaluate the earthquake resistance capacity of a frame taking account of the possibility of brittle fractures. In this paper, seismic response analyses, considering the effects of brittle fractures at beam-ends during an earthquake excitation, are carried out for steel frames. The response properties are compared to those of ductile frames and the effects of fractures on the seismic response of steel frames are discussed.

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We ve known a large earthquake effect with a plastic strain to any structural steel . Structural steel received a plastic strain by cyclic loading which as a large earthquake. But the factors of brittle fracture are not cleared. We produce a specimen to previous that point is to pick out fracture toughness specimens after cyclic loading experiment. This paper reports the difference of mechanical properties between virgin structural steel and strained structural steel. As a result of Charpy impact test, Tensile test and CTOD test, we introduce a fit function of fracture toughness, which agreed well the test results.

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Numerical analyses on buckling-restrained unbonded braces fixed in a frame were made using the non-linear finite element method and the following conclusions were obtained. 1) The hysterisis charachteristics and strain distributions of core steels on "frame model" are almost same as those on "basic model (non-eccentricity and no-moment model)." 2) The hysterisis charachteristics on "obliquely loaded model" are almost same as those of "basic model" although the strain distributions of core steels on "obliquely loaded model" are slightly larger at the end parts than those on "basic model." 3) Locally concentrated cumulative plastic strains of core steels due to earthquake are much small in comparison with cumulative plastic strain of steel to low cycle fatigue failure. 4) The hysterisis characteristics and strain distribution of extremely long unbonded braces are almost same as those of "basic model."

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In this paper, the vertical bearing strength of interior joints between steel beams and reinforced concrete columns is studied. The specimens were designed in order to investigate the effect of bearing failure. The major design parameters varied in the specimens were depth of flange,main reinforcement ratio,and axial load level. The prediction method of the ultimate strength of the joint was proposed to evaluate the effects of different variables. The predicted results gave good agreements with the test results. Furthermore,the bearing strength characteristics of the joint is discussed in this paper.

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In cold-formed steel-deck concrete composite slab systems, there are quite few theoretical and experimental studies on seismic in-plane shear transfer mechanism of composite floor slabs having bottomless trench ducts for cellular raceway systems. Herein, experimental studies are conducted by using fourteen different full-scale test specimens with and without a bottomless trench duct. During the test, alternately repeated in-plane lateral forces are applied to all the specimens on the laboratory test floor, and complete hysteresis loops for load and deformation relations are obtained. Test results indicate that the composite floor slabs with a bottomless trench duct have adequate initial stiffness and strength in case when the steel-decks are sufficiently welded onto the steel supporting girders.

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The notion of "size effect" is shown to contain inherent conceptual difficulties. A new framework to be called "shape effect theory", incorporating "shape" as a key variable in place of "size", is proposed to overcome those difficulties. Several cases of pullout rupture of concrete anchors and flexural rupture of beams are analyzed satisfactorily using this framework. Furthermore, a hypothesis of "hidden dimensions" is proposed to alert to a possibility that an apparent size effect that is really a shape effect is related to some hidden dimensions in the object that are ignored in the theoretical model used for observation.

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Simple predictive formulas for the fire temperatures in the room of origin and the connected corridor are proposed. These are obtained by applying to ventilation controlled fire an existing simple formula for predicting pre-flashover compartment fire temperature proposed by Quintiere et al. These can be used to predict the temperatures in the fire room and the corridor when the room fire is in a ventilation controlled regime. The results of the prediction using the simple formulas are compared with the predicted values with a more detailed computer model. It is considered that the accuracy of the equations is reasonable for many practical applications.

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This report proposes a practical minimum weight design method controlled by the structural performance ( the maximum story displacement and the member safety ratio for allowable stress in elastic design)' which the structural engineer specified, for elastic steel frame. This method is based on Nakamura-Kosaka's strain controlling theory and uses neural network. This method will be effective tool for structural engineer in structural planning stage, because this method can grasp on the structural cost and performance easily. This report shows that neural network is an effective tool for the inverse design problem which is difficult to expand theoretically, using the examples.

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