Browsing by Author "Yen, SI"

Now showing 1 - 5 of 5

A strength superposition method for steel reinforced concrete (SRC) beam-column design
(1995)
Weng, CC
;
Yen, SI
;
交大名義發表
;
National Chiao Tung University
Comparisons of concrete-encased composite column strength provisions of ACI code and AISC specification
(2002-01-01)
Weng, CC
;
Yen, SI
;
土木工程學系
;
Department of Civil Engineering
In the ACI-318 code (1999) and AISC-LRFD specification (1993), different approaches are used for the design of concrete-encased composite columns. The calculated member strengths based on these two design provisions may show significant difference in some cases. The objective of this study is to investigate the difference between these two approaches and to evaluate the accuracy of their strength predictions by comparing to 78 physical test results done by previous researchers. This comparative study indicates that the ACI-318 approach generally gives closer predictions than the AISC-LRFD does. The statistical results show that the ACI-to-experimental capacity ratio has a mean value of 0.90 with a coefficient of variation (COV) of 15% and the AISC-to-experimental capacity ratio has a mean value of 0.73 with a COV of 21%. Also investigated herein are the difference of design philosophy between the design provisions, the failure mode of the tested specimens, the column strength interaction diagram, and the effect of steel ratio on the accuracy of the strength predictions. (C) 2001 Elsevier Science Ltd. All rights reserved.
Experimental study on shear splitting failure of full-scale composite concrete encased steel beams
(2002-09-01)
Weng, CC
;
Yen, SI
;
Jiang, MH
;
土木工程學系
;
Department of Civil Engineering
Presented herein is an experimental study that focuses on the shear splitting failure of composite concrete encased steel beams. Nine full-scale specimens were constructed and tested in this study. Significant horizontal cracks along the interface of steel flange and concrete, referred to as the shear splitting failure, appeared in five tested specimens. Observations from the experiments indicate that the steel flange width ratio, defined as the ratio of steel flange width to gross section width, has a dominant effect on the shear splitting failure of composite beams. The test results reveal that the shear splitting failure occurs when the steel flange width ratio of a composite beam reaches 0.67. The test results also show that the application of shear studs has a positive effect on preventing this type of failure for beams with large steel flange ratio. In addition to the experimental study, a new method for predicting the failure mode of composite beams is proposed. The proposed method gives satisfactory predictions as compared to the test results. Finally, a new equation is derived for the design of the stirrups to prevent shear splitting failure of naturally bonded composite beams.
Shear strength of concrete-encased composite structural members
(2001-10-01)
Weng, CC
;
Yen, SI
;
Chen, CC
;
土木工程學系
;
Department of Civil Engineering
This study investigates the shear strength of composite steel and concrete members in which the steel shape is fully encased in concrete. Two types of shear failure-diagonal shear and shear bond-are examined in this study. Through understanding of these failure modes, a new approach is proposed to predict the shear capacities of composite members. Major parameters investigated include steel flange width, shear reinforcement, concrete strength, and applied axial load. To evaluate the accuracy of the proposed approach, a verification analysis is made by comparing shear capacities predicted by the proposed approach with previous test results. Furthermore, the shear capacities predicted by the proposed approach are also compared with those obtained by American and Japanese provisions. The results of the analysis and comparison indicate that the proposed approach yields satisfactory prediction of shear strength and provides a rational explanation on the mechanism of shear bond failure. A new term, the critical steel flange ratio, is introduced to distinguish the shear bond failure from the conventional diagonal shear failure.
Simplified design approach for cold-formed stainless steel compression members subjected to flexural buckling
(2005-12-01)
Lin, SH
;
Yen, SI
;
Weng, CC
;
土木工程學系
;
Department of Civil Engineering
The design criteria of stainless steel compression member are more complicated than those of carbon steels due to the nonlinear stress strain behavior of the material. In general, the tangent modulus theory is used for the design of cold-formed stainless steel columns. The modified Ramberg-Osgood equation given in the ASCE Standard can be used to determine the tangent modulus at specified level of stresses. However, it is often tedious and time-consuming to determine the column buckling stress because several iterations are usually needed in the calculation. This paper presents new formulations to simplify the determination of flexural buckling stress without iterative process. Taylor series expansion theory is utilized in the study for numerical approximations. The proposed design formulas are presented herein and can be alternatively used to calculate the flexural buckling stress for austenitic type of cold-formed stainless steel columns. It is shown that the column strengths determined by using the proposed design formulas have good agreement with those calculated by using the ASCE Standard Specification. A design example is also included in the paper for cold-formed stainless steel column designed by using the ASCE Standard equations and the proposed design formulas. (c) 2005 Elsevier Ltd. All rights reserved.