Based on the establishment of the unified formulas for control of fluctuation wind induced vibration response of tall buildings with five kinds of passive dynamic absorbers (TMD, TLCD, LCVA, C TLD, R TLD), the unified computing formulas of equivalent structural damping ratio for the controlling effect of passive dynamic absorbers on fluctuation wind induced vibration response of tall building and the design method of optimum parameters for passive dynamic absorbers have been derived.

Then, a simplified computational model of damping isolation systems is established for JZ20 2MUQ platform structure. The relationships between the parameter of isolation layer and structural damping ratio, including their vibration suppressed effect on the whole structure and the relative displacement of isolation layer are studied.

Also the relations between damping layer parameters and the structural damping ratio including the relative displacement control effect of structure and damping layers are studied. And the numerical simulation under wave force or earthquake force is carried out.

This paper discusses the principal factor,the structural damping ratio affecting response spectrum in code of seismic design of highway bridges. Through comparative analysis of domestic and foreign response spectrum modification formulas,the paper also proposes a modification method for the response spectrum in the code when the damping ratio of the spectrum is not 5%. The proposed method herewith provides reference basis for revising the code and for seismic design of highway bridges.

The obtained results show that, in a certain range, earthquake ground motion models, site conditions and structural damping ratio have much influence on the zero-crossing rate of acceleration response of a structure, but have little effect on variation coefficients of response spectra.

In this paper,a new method of high precision calculation for damping ratio,namedZOOMBDFT" and some examples are introduced.It is poined out that the traditional method of 1K bytes FFT is not appropriate to the calculation of structural damping ratio,and the key tactor affecting the precision in the calculation by using half power bandwidth method lies in the sampling duration T.Two criteria upon which to guarantee the accuracy in the damping calculation are set up.

The basic computational process of frequency-domain method is presented in order to highlight some parameters crucial to results of computation, including number of contributing modes, coupling terms between modes, vertical fluctuating components of wind, coherence function and structural damping ratio.

The logarithmic structural damping ratio for each mode is assumed to be 0.02.

A sectional model testing study on flutter control of the Tiger Gate Bridge by using tuned mass damper was carried out in T-J1 Boundary Layer Wind Tunnel in Tongji University. The control effectiveness was confirmed through the test, and the effects of the variance of parameters,such as structural damping, shape of the deck cross section, frequency ratio of TMD to bridge and damping of TMD, on the control effectiveness were also investigated. The new results are shown as follows: ① It is more effective for TMD...

A sectional model testing study on flutter control of the Tiger Gate Bridge by using tuned mass damper was carried out in T-J1 Boundary Layer Wind Tunnel in Tongji University. The control effectiveness was confirmed through the test, and the effects of the variance of parameters,such as structural damping, shape of the deck cross section, frequency ratio of TMD to bridge and damping of TMD, on the control effectiveness were also investigated. The new results are shown as follows: ① It is more effective for TMD to control flutter of bridges with lower structural damping ratio than those with higher structural damping ratio; ② It is more effective for TMD to control flutter of bridges with "more bluff" deck cross section than those with "more streamlined" deck cross section; ③ Frequency ratio of TMD to bridge and damping ratio of TMD have both effects on the control effectiveness,and the effect of the former is greater than that of the latter.

In this paper,a new method of high precision calculation for damping ratio,namedZOOMBDFT" and some examples are introduced.It is poined out that the traditional method of 1K bytes FFT is not appropriate to the calculation of structural damping ratio,and the key tactor affecting the precision in the calculation by using half power bandwidth method lies in the sampling duration T.Two criteria upon which to guarantee ...

In this paper,a new method of high precision calculation for damping ratio,namedZOOMBDFT" and some examples are introduced.It is poined out that the traditional method of 1K bytes FFT is not appropriate to the calculation of structural damping ratio,and the key tactor affecting the precision in the calculation by using half power bandwidth method lies in the sampling duration T.Two criteria upon which to guarantee the accuracy in the damping calculation are set up.

The objective of this paper is to establish a practical design method based on the design code for controlling wind induced vibration of tall buildings with passive absorbers. In the paper, the calculation formulas for equivalent structural damping ratio of control effect of passive absorbers for fluctuating wind vibration responses of tall buildings are derived. From this, a practical design method for controlling wind induced...

The objective of this paper is to establish a practical design method based on the design code for controlling wind induced vibration of tall buildings with passive absorbers. In the paper, the calculation formulas for equivalent structural damping ratio of control effect of passive absorbers for fluctuating wind vibration responses of tall buildings are derived. From this, a practical design method for controlling wind induced vibration of tall buildings with passive absorbers is presented based on both the load code of building structures and the structural design code of tall buildings. The calculation results by the method for the Shanghai Central Plaza, wihich is a thirty nine story reinforced concrete building with rectangular TLD,indicate that (1)The control effects of passive absorbers can be easily quantified and programmed into some common structural analysis programs for the design of tall buildings. (2)The method can be codified and its calculation results can be directly compared to the results of current structural design of tall buildings.