Abstract
Tuned liquid dampers (TLDs) have received considerable attention as effective passive dynamic
vibration absorbers for controlling wind-induced vibrations in high-rise buildings. However, due to the complex
coupled response of the structure-TLD system, accurately evaluating the damping performance of TLD is
challenging. This study proposes a method to evaluate damping performance through the coupled vibration response.
First, a state space model of the structure-TLD system is built. Second, a state space technique is used to determine
the state matrix of the coupled system and obtain the modal frequencies, damping ratios, and mass ratios of the bare
structure and TLD. Third, damping performance is estimated by calculating the structural frequency response
function before and after TLD control on the basis of the identified parameters. Last, the proposed method is
validated preliminarily by using a numerical example and applied to the coupled vibration response of a 260 m high
rise building and TLD system. Results show that the identified values of the modal parameters are in good agreement
with the design values. The maximum absolute error of TLD damping performance estimated with the identified
parameters is only 4.7% compared with the results calculated by numerical simulations. These findings fully
demonstrate the accuracy of the method and the feasibility of its application to the performance evaluation of
structure-TLD systems with field measurements.
Address
Lanfang Zhang:State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou, 510641, China
Zijie Zhou:1)State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou, 510641, China
2)Guangzhou Jishi Construction Group Co. Ltd, Guangzhou, 510115, Chin
Zhuangning Xie:State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou, 510641, China
Lele Zhang:China Construction Seventh Engineering Division Corp., Ltd.
Houjun Huang:Guangzhou Jishi Construction Group Co. Ltd, Guangzhou, 510115, China
Abstract
This paper employed the Bayesian spectral density approach (NewBSDA) that incorporates aerodynamic
characteristics to identify the dynamic parameters of the 280-meter Shenzhen Zhuoyue Century Center (ZCC) during
Typhoons Hato, Pakhar, and Mangkhut. Variations in modal frequencies and damping ratios were analyzed, and a
detailed comparison was made between field measurements and wind tunnel results to investigate the causes of
discrepancies.Results show that (1) The maximum peak acceleration under all three typhoons occurred in the north
south direction. During Typhoon Mangkhut, a peak acceleration of 23.9 milli-g was recorded—an exceptionally high
value rarely observed in field measurements of super high-rise buildings. (2) Modal frequencies decreased over time
but recovered after strong wind-induced vibrations. A multi-value pattern emerged in the frequency-amplitude
relationship during Typhoon Mangkhut. (3) Damping ratios were higher under strong winds compared to those in
breezy conditions. Their correlation with amplitude was weaker than their correlation with time. (4) Wind tunnel and
field measurement results showed good agreement when a broader range of real terrain conditions was considered.
This suggests that the upstream terrain roughness specified by the Chinese Code, as applied in prior wind tunnel tests,
tends to be conservative.
Key Words
field measurement; modal parameter identification; super high-rise building; terrain simulation
test; typhoon; wind tunnel test
Address
Jing Duan:Guangdong Construction Polytechnic, Guangzhou 510440, China
Lele Zhang:China Construction Seventh Engineering Division Corp., Ltd., Zhengzhou, 450004, China
Biqing Shi:State Key Laboratory of Subtropical Building Science, South China University of Technology,
Guangzhou, 510641, China
Abstract
The aerodynamic characteristics of vehicles moving on bridges under crosswinds are critical factors for
accurately assessing their safety and comfort when traveling on long-span bridges and directly impact the normal
operation of the bridge, whereas most previous studies have primarily focused on vehicles in ground scenarios or
stationary states. In this paper, the real movements of a large tractor-trailer on a highway bridge deck with six traffic
lanes and on flat ground were simulated simultaneously based on the computational fluid dynamics (CFD) numerical
simulation platform using the overset mesh technique, and the flow features and aerodynamic forces of the moving
vehicle under the effect of crosswinds were investigated in detail. The results show that the flow features of the moving
vehicle under crosswinds are mainly related to the yaw angle of the relative wind (synthesized by the wind velocity
and vehicle velocity), which leads to the aerodynamic forces of the moving vehicle as functions of the synthesized
wind yaw angle. Furthermore, the presence of the bridge deck reduces the side force and yawing moment of the vehicle
but increases the rolling moment to a certain extent compared to the simulation results of the ground case, and such
effects are also related to the position of the traffic lane in which the vehicle is traveling on the bridge deck. Finally,
empirical equations for the aerodynamic coefficients of the vehicle traveling on the bridge deck with respect to the
synthetic wind yaw angle are developed for engineering applications.
Key Words
aerodynamic characteristic; CFD simulation; moving vehicle; overset mesh; wind-vehicle-bridge
system
Address
Jiaming Zhang:1)China Railway Eryuan Engineering Group Co., Ltd., Chengdu, Sichuan, China, 610031
2)School of Civil Engineering, Central South University, Changsha, Hunan, China, 410083
F. Rizzo, A.M. Avossa, D. Foti, S. Gillmeier, R. Hoeffer, J.B. Jakobsen, A.K.R. Jayakumari, R. Klaput, A. Malasomma,
A. Pistol, U. Winkelmann, F. Ricciardelli
Abstract
The ERIES-WhICH ROUGH Project was funded under the framework of the Horizon 2020, INFRA
2021-SERV-01-07 program. Its main goal is to assess the effects of wind profile transitions between different terrain
roughness categories on the actions exerted on a high-rise building, with the final aim of devising a simplified loading
model for the purpose of codification. Experiments were carried out at the TU/e wind tunnel facility in Eindhoven on
a rectangular plan building model featuring the same ratios of dimensions B, D and H as those of the CAARC
building. Three setups with uniform roughness were created in the wind tunnel, together with eight transitions
between each pair of uniform roughness values. For each of the twenty-seven setups so obtained, instantaneous wind
velocity profiles were measured, together with the instantaneous pressure distribution on the model building for three
angles of incidence. Finally, the overall aerodynamic forces were derived from integration of surface pressures. This
paper is meant to present the experimental campaign and the data that will be made available to the scientific
community to provide a reference for their future exploitation. The measurements showed a clear evolution of the
transition mean wind profiles with changing distance from the roughness discontinuity. Pressure loading patterns also
change depending on distance from the discontinuity, and a relationship could be found between the profiles and the
mean pressure distributions.
Abstract
This study examines the effects of parapet porosity on the aerodynamic loads on roof-mounted
photovoltaic (PV) panels. Wind tunnel tests were carried out in the ZD-1 boundary-layer wind tunnel at Zhejiang
University to capture the wind pressure variations on the PV panels under different levels of porosity. A rigid model
with a scale ratio of 1:50 was fabricated, mimicking a low-rise building with five rows of PV panels on the roof. Four
distinct levels of parapet porosity (81%, 49%, 25%, and no parapet) were tested at a fixed panel tilt angle of 5°. The
methodology and results are presented, highlighting the statistical analysis of wind pressure coefficients,
encompassing means, standard deviations and the identification of maximum and minimum peak values in various
wind directions. Key findings reveal that oblique wind directions (30°–75°, 120°–165°) generate peak pressure
extremes through conical vortex formation at roof edges, with maximum mean pressure coefficients reaching 2.27
(30°) and -2.63 (135°) in the no parapet case. It is observed that while parapets can attenuate wind loads, their
effectiveness in load reduction is affected by the porosity of the parapet. Optimal parapet porosity (49–81%) reduces
mean and extreme pressure coefficients by up to 60.3% and 51.7% in front-row modules. In comparison, when the
porosity is further decreased from 49% to 25%, the mean and extreme pressure coefficients only show a limited
reduction (<10%), while localized pressures are exacerbated.
