Site-Specific Earthquake Ground Motions for Seismic Design of Port Facilities in Indonesia

Self Cite

Fiber-based finite element analysis (FB-FEA) has been widely recognized for its ability to reproduce experimental results and is also a reliable method for evaluating the nonlinear seismic response of pile-supported wharves (PSWs). Design practice often employs frame analysis (FA) due to its easy implementation. To precisely reproduce the nonlinear seismic response of PSW using FA, it is necessary to configure mechanical properties such as the hinge property correctly. However, it is unclear whether the hinge properties proposed in previous studies can be applied to PSWs with spun piles. In this study, a novel FA method was developed to investigate the nonlinear seismic response of PSWs with corroded spun piles considering PC bar area reduction, deteriorated material properties, the bending stiffness reduction factor, and the moment–curvature relationship of the spun pile. The nonlinear seismic response of corroded PSWs was determined by performing pushover analysis using three methods: FA using the method of the previous study (FA-1), the proposed FA method (FA-2), and FB-FEA. As regards PSW foundations, vertical pile and batter pile configurations were considered. The pushover analysis results were compared in terms of several parameters, such as the natural period, plastic hinge formation, and load capacity of the corroded PSWs. The FA-2 results agreed very well with the FB-FEA results, while the FA-1 results were less precise with respect to the natural periods and load capacities of corroded PSWs. The results indicated that the bending stiffness reduction factor, moment–curvature relationship, and axial load–bending moment (P–M) capacity of the corroded spun piles should be appropriately defined. Corrosion had greater negative impacts on the compressive axial load and bending moment capacities of the spun pile than on its tensile axial load capacity.

Section: Bending Stiffness Reduction Factor Of Corroded Spun Pilementioning

confidence: 99%

Simplified Method for Nonlinear Seismic Response Analysis of Corroded Pile-Supported Wharf

Refani,

Nagao

2023

Self Cite

“…To investigate the effect of waveform duration on the seismic response of PSW, this study employed two distinct waveforms: short-duration waveform (SDW) and longduration waveform (LDW). We used two reference waveforms observed in Indonesia [37], as shown in Figure 3. These waveforms were modified to match the target SA on Indonesian site class E [37] (Figure 4).…”

Section: Input Waveformsmentioning

confidence: 99%

“…We used two reference waveforms observed in Indonesia [37], as shown in Figure 3. These waveforms were modified to match the target SA on Indonesian site class E [37] (Figure 4). The following procedures were implemented based on the observation that the frequency characteristics of the Fourier spectrum of a waveform and SA are similar [38].…”

Section: Input Waveformsmentioning

confidence: 99%

Seismic Performance Assessment of Wide Pile-Supported Wharf Considering Soil Slope and Waveform Duration

Boyke

Nagao

2022

Self Cite

Pile-supported wharf (PSW) is one of the primary port structures and is often damaged by earthquakes. To mitigate the risk of seismic damage to a PSW, its seismic performance should be thoroughly assessed. This study aimed to examine the impact of ground displacement on the seismic performance of PSW with a mild soil slope. We performed soil-structure system finite element analysis targeting a wide PSW. The analysis is divided into two scenarios. In the first scenario, the PSW was modeled without regard for the soil slope, whereas the second scenario considered the soil slope. Two waveforms that matched the target spectral acceleration were used to study the effects of the waveform duration on the seismic response of PSW. The analysis results revealed substantial influences of soil slope displacement as well as differences in waveforms on PSW’s seismic performance.

Seismic Performance Assessment of Pile-Supported Wharfs: 2D Frame Analysis Method Considering Both Inertial and Kinematic Forces

Boyke

Nagao

2023

Frame analysis (FA) is known for its efficiency and low computer resource requirements. However, compared to finite element analysis (FEA), the applicability of FA for the seismic performance assessment of pile-supported wharves (PSWs) is limited, particularly in the ability to account for the kinematic force caused by ground displacement during an earthquake. This study aimed to develop a two-dimensional FA method for PSW seismic response analysis that considers a combination of inertial and kinematic forces. We performed FA and FEA and compared the results. First, we targeted the PSW model without considering the soil slope and discussed the spectral acceleration (SA) evaluation method for calculating inertial force. As a result, an equation for estimating a damping coefficient to evaluate the SA in accordance with the PSW width and natural period was proposed. Next, we targeted the PSW model by considering the soil slope and proposed a method to evaluate the kinematic force based on the amount of ground displacement and the soil spring characteristics. The results revealed that using the proposed method, FA, by considering kinematic and inertial forces, could reproduce the bending moments of the piles comparable to those calculated using FEA. Therefore, solely considering the inertial force for a PSW on a soil slope may cause the bending moment to be underestimated.