Applied Seismology for Engineers

A: This achieves a conservative but traceable PGA consistent with the stated attenuation form. Option B double-counts unit conversion and inflates the result. Option C drops the near-field saturation term, reducing demand without basis. Option D swaps distance definitions, pushing PGA unrealistically high at this range.

A: This achieves alignment between expected ground motion and the structure’s dynamic response. Option B misreads S as a damping correction rather than site amplification. Option C overstates its scope and would bypass required studies. Option D treats S as a blanket factor, which Eurocode 8 avoids by soil class.

A: This achieves usable data in the low-frequency band that drives tunnel response. Option B saturates resolution at low frequency despite high shock rating. Option C rolls off below its tuning and misses long-period motion. Option D measures structural strain, not free-field ground motion.

A: This achieves correct orientation so recorded components map to analysis axes. Option B affects traceability but not axis interpretation. Option C is an environmental check, not a coordinate issue. Option D doesn’t affect channel alignment.