Forced-Vibration Tests of a Reinforced Concrete Four-Story Building Structure

2021 ◽  
Vol 147 (7) ◽  
Author(s):  
Jaime De-la-Colina ◽  
Jesús Valdés-González
Author(s):  
I Nyoman Sutarja

This study evaluates the effect of earthquake and tsunami loads on structural behavior of reinforced concrete building with varying heights. The purpose of this study is to evaluates the level of resilience of building structures that are designed to withstand earthquake loads when loaded by tsunami loads. Building structure behavior is evaluated based on the amount of internal forces, displacements and drift ratio. In making models of building structures with varying heights where the plans are planned on their own. The building structure model is planned to be resistant to earthquake loads where the evaluation is carried out on the comparison of static earthquake loads with dynamic earthquake loads and the drift ratio between building floors meets the limits permitted by SNI-1726-2012. Furthermore, the same structural model is loaded with tsunami loads which refers to FEMA P646 in 2012. The magnitude of the planned tsunami load is adjusted to the building height variations, which are buildings 3, 5 and 7 floors. The loading done on the building is earthquake load, combination tsunami load 1 (T1) and combination tsunami load 2 (T2). The results are obtained in the 3-story building structure, the drift ratio due to earthquake load, T1 and T2 still meet the inter-floor permit drift ratio. The maximum drift ratio value on the first floor of a 3-storey building structure due to earthquake loads, T1 and T2 are 0.75%, 0.52% and 1.01%, respectively, which are all smaller than the limits of the drift ratio of buildings categorized as risk IV which is 1%. In the structure of buildings 5 and 7 floors, the value of the drift ratio on the first floor due to earthquake load still meets the requirements (<1%), but conversely due to the load of T1 and T2 at the same floor level, the drift ratio of 5-storey buildings is respectively 1, 44% and 2.13%, while in the 7-story building respectively 2.88% and 4.67%. These results indicate that the 5-story and 7-story building structures are unable to withstand lateral forces due to the planned tsunami load (T1 and T2).


1953 ◽  
Vol 43 (1) ◽  
pp. 7-16
Author(s):  
J. L. Alford ◽  
G. W. Housner

abstract Forced vibration tests were conducted on a four-story reinforced concrete building. Deflections and accelerations were produced which approached the magnitude of those which occur during strong-motion earthquakes. Damping values were calculated from the resonance curves obtained. The results show that the total damping in the structure is small and that the damping apparently increases with increasing amplitude of motion. Within the accuracy of the measurements the damping was independent of the frequency of the motion.


Author(s):  
Amin Hosseini ◽  
Touraj Taghikhany ◽  
Milad Jahangiri

In the past few years, many studies have proved the efficiency of Simple Adaptive Control (SAC) in mitigating earthquakes’ damages to building structures. Nevertheless, the weighting matrices of this controller should be selected after a large number of sensitivity analyses. This step is time-consuming and it will not necessarily yield a controller with optimum performance. In the current study, an innovative method is introduced to tuning the SAC’s weighting matrices, which dispenses with excessive sensitivity analysis. In this regard, we try to define an optimization problem using intelligent evolutionary algorithm and utilized control indices in an objective function. The efficiency of the introduced method is investigated in 6-story building structure equipped with magnetorheological dampers under different seismic actions with and without uncertainty in the model of the proposed structure. The results indicate that the controller designed by the introduced method has a desirable performance under different conditions of uncertainty in the model. Furthermore, it improves the seismic performance of structure as compared to controllers designed through sensitivity analysis.


2007 ◽  
Vol 345-346 ◽  
pp. 1385-1388
Author(s):  
Hee Kyu Kim ◽  
Young Kyun Hong ◽  
Jung Hyun Park

his study was prosecuted to analyze a structural resistance degradation model for the existing column in the 3-story building to be remodeled. The probabilistic random variables in this study were dealt with an initial member strength, current maximum crack width, current density and diameter of reinforcement with elapsed time and corrosion initiation time, TDRA has been performed to calculate the reliability index, the failure probability, the degradation level according to the member strength loss in reinforced concrete columns due to corrosion of steel reinforcement.


1980 ◽  
Vol 69 (3) ◽  
pp. 605-634 ◽  
Author(s):  
RT SEVERN ◽  
AP JEARY ◽  
BR ELLIS ◽  

1977 ◽  
Vol 67 (5) ◽  
pp. 1441-1472
Author(s):  
R. Husid ◽  
A. F. Espinosa ◽  
J. de las Casas

abstract The October 3, 1974, earthquake caused severe damage to buildings of adobe and quincha construction, and also to masonry, reinforced masonry, and reinforced-concrete structures in Lima and vicinity. Most of the damage to well-built structures was due, in part, to the lack of lateral resistance in the original design and to the fact that this earthquake had more energy around 0.4 seconds period than prior destructive earthquakes. Water tanks on the roofs of structures with four or five stories were damaged. Well-engineered single-story buildings were less affected than taller structures. Considerable structural damage to reinforced-concrete structures occurred in the districts of Barranco, La Campiña Molina, and Callao. In La Campiña three-story building partly collapsed and other buildings sustained considerable damage. In La Molina, the buildings of the Agrarian University sustained severe damage, and some collapsed. In Surco, the district adjacent to La Molina, there was no appreciable damage. In Callao, a four-story building collapsed, and the upper half of a concrete silo collapsed. In reinforced-concrete structures, column ties were frequently small in diameter, widely spaced, and not well connected. Usually, the reinforcement of resisting elements had no relation to their stiffnesses. Front columns in school buildings were restrained by high brick walls and had rather short effective lengths to allow building displacement in that direction. The windows in the rear walls gave the rear columns a much greater effective length. Therefore, a longitudinal displacement induces large shear forces in the front columns where most of the severe damage occurred. This problem was not considered in the design of these structures.


Author(s):  
Eunchurn Park ◽  
Sang-Hyun Lee ◽  
Sung-Kyung Lee ◽  
Hee-San Chung ◽  
Kyung-Won Min

The accurate identification of the dynamic response characteristics of a building structure excited by input signals such as real earthquake or wind load is essential not only for the evaluation of the safety and serviceability of the building structure, but for the verification of an analytical model used in the seismic or wind design. In the field of system identification (SI) which constructs system matrices describing the accurate input/output relationship, it is critical that input should have enough energy to excite fundamental structural modes and a good quality of output containing structural information should be measured. In this study forced vibration testing which is important for correlating the mathematical model of a structure with the real one and for evaluating the performance of the real structure was implemented. There exist various techniques available for evaluating the seismic performance using dynamic and static measurements. In this paper, full scale forced vibration tests simulating earthquake response are implemented by using a hybrid mass damper. The finite element (FE) model of the structure was analytically constructed using ANSYS and the model was updated using the results experimentally measured by the forced vibration test. Pseudo-earthquake excitation tests showed that HMD induced floor responses coincided with the earthquake induced ones which was numerically calculated based on the updated FE model.


Author(s):  
O. Gauron ◽  
Y. Boivin ◽  
S. Ambroise ◽  
P. Paultre ◽  
J. Proulx ◽  
...  

2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Zhe Wang ◽  
Liang Cao ◽  
Filippo Ubertini ◽  
Simon Laflamme

The tuned liquid multiple column damper (TLMCD) is a variation of the tuned liquid column damper (TLCD) that includes multiple vertical columns. A new damping system that embeds TLMCDs within reinforced concrete shear wall systems, termed tuned liquid wall damper (TLWD), is proposed, augmenting the traditional structural component with energy dissipation capabilities. The objective of this study is to assess energy mitigation and strength trade-offs in designing TLWDs and demonstrating the promise of TLWD systems in tall buildings through vertically distributed applications. This is done by investigating the performance of the proposed TLWD through the finite element model (FEM) of a simplified representation of a 42-story building equipped with the multifunctional component. A strength model for the TLWD is developed to empower faster performance evaluation on more complex models. Results from the FEM are used to validate the strength model and show that the model could be used conservatively in assessing strength performance. Design considerations are discussed based on the simplified representation. In particular, to improve mitigation performance while maintaining strength, it is found that a single-layer arrangement of the vertical columns is preferred, while distributing the inertia among a higher number of smaller columns. The proposed TLWD is numerically evaluated on a more realistic system consisting of a multi-degrees-of-freedom representation of the 42-story building under stochastic wind excitation. Simulation results demonstrate that the TLWD, used in a vertically distributed configuration through the building, could be used to mitigate vibrations, outperforming a traditional TLCD system with geometric constraints under 20 design wind realization. Results from the numerical simulations also confirmed the design considerations established through the simplified representation.


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