Control Of Reinforced Concerete Frame-Wall Construction Under Earthquake Motions

Earthquake is one of the serious disaster threatening human being's life and belongings. In civil engineering, the most progressive measure to alleviate the affection is structural control. Structural vibration control is widely recognized as an effective way of mitigating catastrophic damage of structures induced by earthquakes.Structural control can be classified as follows: active control, passive control, semi-active control , hybrid control and smartal control.This dissertation studies the theories and methods of analysis and active control of nonlinear seimic responses of reinforced concrete frame — wall structures under earthquake motions.The structures are idealized as the assemblage of prismatic members with rigid zones at ends. A modified element model with varied stiffness in different region is proposed to stimulate the nonlinear behavior of reinforced concrete elements. The plastic flexural stiffness of reinforced concrete elements determined from moment — curvature hysteretic model including the pinching effect are modified to include the effects of axial force fluctuation in columns and walls on the flexural stiffness and strength of reinforced concrete sections. A simple nonlinear shear model, which provides a new concept by considering variation of shear modulus along the wall cross — section depth, is adopted in establishing cross — sectional shear properties in a similar fashion to flexural properties. The effects of slippage rotations at the ends of reinforced elements due to non-perfective bond of reinforcing bars are also included in the hysteresis models. The geometrical non-lineanity is included in the nonlinear dynamic equilibrium equations.For stiffness discontinuous points in the piecewise linear hysteresis model, an algebraic method is presented for dealing with these stiffness discontinuous points . For the active control of nonlinear seismic responses of reinforced concrete frame — wall structures subjected to earthquake motions, this dissertation has established the incremental instantaneous optimal control algorithm. The dissertation has programmed the computer code of artificial earthquake wave simulating program which included the effects of earthquake magnitude, epicenter distance and site conditions and directly fitting the given target response spectrum, the nonlinear seismic responses analysis program of reinforced concrete frame — wall structures subjected to earthquake motions, and the program of active control of nonlinearseismic responses of reinforced concrete structures under strong earthquake environmental. All the programmed codes are tested. The computed results, are tested against those of the actual damages, and it show that the calculated results are reliable.