Predicting Dynamic Capacity Curve of Elevated Water Tanks: A Pushover Procedure

Abstract

Despite the importance of water tanks for water supplies and supporting the community resilience through the firefighting usages in catastrophic conditions, post-earthquake situations especially, a few studies have been done on seismic behavior of water tanks so far. The scope of this paper is to propose a new pushover procedure to evaluate seismic responses of elevated water tanks (EWT) supported on the concrete shaft in the form of dynamic capacity curves (i.e. base shear versus top displacement). In this regard, a series of shaft supported EWTs are simulated considering soil-structure and fluid-structure interactions. The shaft is modelled with frame elements and plastic hinges are assigned along the shaft to consider the material nonlinearity. The effect of soil-structure interaction and fluid-structure interaction are considered through the well-known Cone model and modified Housner model, respectively. At first, parametric studies have been conducted to investigate the effects of various essential parameters such as soil type, water level and tank capacity on seismic responses of EWTs using incremental dynamic analysis (i.e. nonlinear-time-history-analyses with varying intensities). Thereafter, pushover analyses as nonlinear static analyses are performed by variation of lateral load patterns. Finally, utilizing these results and comparing them with mean IDA curve, as an exact solution; a pushover procedure based on the most reliable lateral load patterns is proposed to predict the mean IDA curve of the EWTs supported on the concrete shaft. The obtained results demonstrate the accuracy of the proposed pushover procedure with errors limited to 30 % only in the changing stage from linear to nonlinear sections of the IDA curve.

Stability Analysis of a Real Life Tilted RCC Over Head Reservoir (Tank) considering Soil-Structure and Fluid-Structure Interaction

“…The drift limits varied significantly from the drift limits of building frames; indicating the seismic behaviour of frame staging for Elevated Water Tanks was different than the building frames. Afshin Mellati [19] proposed a new pushover procedure to evaluate the seismic responses of Elevated Water Tanks supported on the RCC shaft staging considering soil-structure and fluid-structure interactions. Parametric studies were conducted to investigate the effects of various essential parameters like soil type, water level and tank capacity on seismic responses of EWTs using Incremental Dynamic Analysis to generate fragility curves for the assessed conditions of the tanks.…”

Pushover Response of Multi Degree of Freedom Steel Frames

“…Figure 2 shows how to obtain the inelastic design response spectrum (IDRS) starting from a linear elastic design response spectrum (LEDRS) using the ductility factor μ [11]. However, there have been suggestions that by using this approach for Multi-Degree-Of-Freedom (MDOF) systems, q can be overestimated by a factor of two in some cases [12].…”

Evaluasi Kinerja Gedung a Universitas Pembangunan Jaya Dengan Pushover Analysis Berdasarkan Fema 356

“…Evaluasi kinerja bangunan berlantai banyak dengan menggunakan metode pushover analysis juga dilakukan oleh beberapa peneliti (Yuswanto, 2019;Shinde, 2014;Siswanto, 2023). Selain itu metode ini juga dapat diterapkan pada bangunan eksisting yang sudah beroperasi, seperti pada evaluasi kinerja bagunan rumah sakit (Kadarusman, 2017), bangunan hotel (Purnomo, 2014;Putri, 2021), jembatan (Mahardika, 2021), dan tangki air (Mellati, 2018;Gowriswaran, 2017).…”