Duration Effects of Near-Fault Ground Motions on Structural Seismic Responses

ABSTRACT

This study reveals the duration effects of near-fault ground motions with distinct long-period pulse and without pulse on structural seismic responses and damage. To this end, several velocity-based duration measures (DMs) are proposed according to the characteristic of abundant low-frequency content in near-fault records, and non-structural compound intensity measures (IMs) incorporating DMs are suggested. Moreover, the correlations between the IMs and DMs of near-fault ground motions, as well as those between the IMs and DMs of ground motions and the seismic responses (i.e. maximum displacement D_max, input energy E_I and hysteretic energy E_H) of bilinear single-degree-of-freedom (SDOF) systems, are scrutinized. It is shown that the acceleration-based absolute uniform durations present strong correlation with the acceleration-related IMs, while the velocity-based absolute uniform durations highly correlate with the velocity- and displacement-related IMs. In the short-period region, the acceleration-based absolute uniform duration U_0.10 g is well correlated with the seismic responses, while in the medium-, medium-long- and long-period regions, the velocity-based absolute uniform duration U_v10 exhibits strong correlation. Additionally, the compound IMs combining with uniform durations (PGA•U_0.10 g and PGV•U_v10) are the competent indices to quantify duration effects of near-fault records. The similar observations for duration effects are validated by four representative frame buildings considering Bouc-Wen hysteretic behavior without or with degradation of strength and stiffness.

KEYWORDS:

• Near-fault ground motions
• intensity measures
• duration effects
• bilinear SDOF systems
• Bouc-Wen hysteretic frame buildings
• seismic responses

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The supports of the National Natural Science Foundation of China [Grant Nos. 12032008, 12102080], the China Postdoctoral Science Foundation [Grant No. 2019M661088], and the Key Science and Technology Program of Henan Province of China [Grant No. 212102310949] are much appreciated.