The HOT DUCTILITY of IMI834 alloy in two conditions of first HOT rolling and second HOT rolling has been studied by conducting tensile tests with a strain rate of 0.1 s−1 and temperature range of 800–1000°C. In first HOT rolling condition, IMI834 alloy showed little HOT DUCTILITY in the temperature range 800–900°C and DUCTILITY loss occurred at 850°C. In second HOT rolling condition, HOT DUCTILITY increased at all temperatures and DUCTILITY loss is not occurred. Especially at 900°C, HOT DUCTILITY increased from 31% in first HOT rolling to 95% in second HOT rolling.

The aim of this study was to investigate the behavior of HOT deformation and occurrence of restoration phenomena during the deformation of AISI H10 HOT work tool steel. For this purpose, HOT tensile test was performed on the steel in the temperature range of 900-1150 º, C with a temperature interval of 50 º, C and at a constant strain rate of 0. 1s-1. The microstructures were examined and the curves of HOT flow and DUCTILITY were drawn. According to the curves and microstructures, DUCTILITY was lower at temperatures of 900 º, C and 950 º, C due to inactivity of repair processes and the presence of carbides. DUCTILITY increased in the temperature range of 1000-1100 º, C due to the occurrence of dynamic recrystallization. Finally, DUCTILITY decreased in the temperature of 1150 º, C due to the dissolution of carbide particles and grain growth. The results obtained from HOT tensile test and microstructural studies at a constant strain rate of 0. 1s-1 revealed that the appropriate temperature range for deformation of AISI H10 HOT work tool steel was 1000-1100 º, C.

The possible DUCTILITY troughs of tough pitch copper containing various oxygen contents were identified to determine the safe and unsafe thermomechanical processing domains. Tensile and compression tests were conducted in temperature range of 300-800°, C. The critical strain of single/multiple peaks dynamic recrystallization decreased by increasing oxygen content up to 220 ppm, and again increased with further increment up to 390 ppm. The non-uniform elongation region increased by increasing the temperature, and above 500°, C, it was the dominant portion of the tensile curves. The long post-uniform elongation was attributed to the occurrence of dynamic recrystallization which increased the resistance of the material to localized necking. Two DUCTILITY troughs (unsafe thermomechanical processing regions) were recognized at temperatures of 400±, 50°, C and 600±, 50°, C. The DUCTILITY drop regions shifted to lower temperatures with an increase in the strain rate. The variation of the oxygen content, however, did not have significant effects on the position of DUCTILITY drops. The current work also explores the fracture surface characteristics of the tensile tested specimens.

This paper investigates the effect of curvature of structural members on nonlinear behavior of two-dimensional building frames. The RC moment resisting frames in two groups of medium (M) and high DUCTILITY (H) level, on alluvium (A) and bedrock (R) soil were considered for the analysis respectively.Totally, sixteen frames having 5, 8, 12 and 15 stories, with four bays of each 4m long, were considered.All frames were designed for H and M DUCTILITY levels according to Iranian standard 2800 for seismic design, and Iranian concrete code of practice (ABA) and then corresponded to the regulation of ACI- 2002.IDARC computer program is utilized for the nonlinear static analysis to investigate the capability of plastic hinge formation of different members during the various state of behavior (cracking, yielding and ultimate state). Linear relation between the overall curvature DUCTILITY and the overall displacement DUCTILITY of the multi-degree of freedom system is derived. From the derived relationship, the close relationship between the fundamental period and the relative energy dissipated (ratio of overall curvature DUCTILITY to the overall displacement DUCTILITY) is clearly obtained.

Experimental studies show that an indeterminate structure or a continuous concrete beam does not fail when critical sections reach their ultimate strengths. Therefore, if a structure has adequate DUCTILITY, stress and moment redistribution will take place in the flexural members by developing plastic hinges at critical sections. This causes the other points of beams to achieve their ultimate strengths and capacities. Besides, moment redistribution allows designers to adjust the bending moment diagram computed by elastic analysis.The usual result is a reduction in the values of negative moments at the support face as well as an increase in the values of positive moments along the span.In the current investigation, a parametric study on moment redistribution in continuous RC beams with equal spans under uniform loading was performed. First, the governing equation for the allowable percent of moment redistribution was extracted using DUCTILITY demand and DUCTILITY capacity concepts. The effects of different parameters such as the concrete compressive strength, the amount and the strength of reinforcing steel, the magnitude of elastic moment at the support and the ratio of the length to the effective depth of the continuous beam on moment redistribution were then investigated. Furthermore, the allowable moment redistributions were calculated according to the regulations of different codes in each case. The results showed that, whereas the permissible moment redistribution in continuous reinforced concrete beams based on the relevant rules in the current codes is not in a safe margin in some cases, it is rather conservative in most cases.

In seismic areas, DUCTILITY is an important factor in the design of high strength concrete (HSC) members under flexure. In order to investigate this, here in this study, eight HSC beams with different percentages of  r & r’ were cast and incrementally loaded under bending. During the test, the strain on the concrete middle faces, the tension and compression bars, and also the deflection at different points of the span length were measured up to failure. Based on the obtained results, the serviceability and ultimate behavior, and especially the DUCTILITY of the HCS members are more deeply reviewed. Also a comparison between theoretical and experimental results is reported here.

In this paper, results of experimental and analytical studies on a new type of infilled frames, having high DUCTILITY are presented. The studied infilled frames, regarded Engineered, had frictional sliding fuses at their midheights.The fuse could be regulated for a desired sliding strength in longitudinal direction, but was restrained transversally. In the first part of the paper, experimental results of two engineered infill specimens, with different sliding strengths of their fuses, are presented. Cyclic loads were applied to the specimens. It is shown that such infills have more stable hysteresis loops as well as higher ductilities, in comparison with regular infill panels.After having the experience of failure by in-plane loads, the specimens were tested again; one of them was repaired by grout and reloaded by the same loading protocol. The other one was loaded transversally to evaluate the out-of-plane strength of the engineered infills after being failed by in-plane loads. Results show that such infills have high transversal strengths and they can be efficiently repaired by grout. In the second part, behavior of the engineered infilled frames (EIFs) in real earthquakes are studied and compared with ones of bare frame and regular reinforced concrete infilled frame. For this, some nonlinear time-history analyses of a three bay frame with 1, 3, 5 and 7 stories were conducted by IDARC for five earthquake records. It is shown that the engineered infilled frames are efficient to improve seismic behavior of the considered buildings.

Self-consolidating concrete (SCC) is a relatively new approach to making concrete, and it is characterized by its high flowability and resistance to aggregate segregation in the plastic state. A total of 3 beams were tested in this experimental investigation on the flexural DUCTILITY of reinforced concrete beams made with self-consolidating concrete. The beams were made from concrete having average compressive strength of 30 MPa and reinforcement ratio in the range of 0.15-1.38. Three self-consolidating reinforced concrete beams with different percentage of and constant amount of were cast and incrementally loaded under bending. During the test, the strains on the concrete middle face and on the tension and compression bars as well as the deflection at different points of the span length were measured up to failure. This paper compares the DUCTILITY of reinforced beams cast with SCC concrete to the theoretical calculations based on two codes (ACI, CSA) recommended for the reinforced concrete members that vibrated into place to ensure proper filling and consolidation. Based on the results obtained, effect of increasing tension reinforcement on the curvature and displacement DUCTILITY of the self-consolidating concrete reinforced members is more deeply reviewed. Comparisons between theoretical and experimental results are also reported here. Generally, it was concluded that, self-consolidating reinforced concrete beams yielded greater DUCTILITY as opposed to the theoretical calculations based on two codes (ACI, CSA) recommended on conventional reinforced concrete beams.