Seismic Test of Prefabricated Panel Houses

The seismic test of prefabricated panel houses primarily involves simulating ground motion using a seismic test platform, combined with vibration testing equipment and standards to evaluate their seismic performance.

I. Test Methods and Core Equipment

The core of seismic tests for prefabricated panel houses is simulating ground motion. These tests are typically conducted on a seismic test platform, where earthquake wave parameters specified by national standards (such as acceleration, frequency, and duration) are input to simulate earthquake scenarios of varying intensities. During testing, vibration testing equipment (such as accelerometers, displacement gauges, and velocity meters) is used to collect real-time dynamic response data from the house, including parameters like acceleration, velocity, and displacement. Additionally, dynamic characteristic tests are performed to obtain key indicators such as the house's natural vibration period and damping ratio, which serve as the basis for evaluating seismic capacity. For example, houses with excessively long natural vibration periods are prone to resonance during earthquakes, leading to increased damage; whereas a higher damping ratio reflects the house's ability to dissipate seismic energy, indicating better seismic performance.

II. Evaluation Standards and Key Indicators

Test results must be evaluated in accordance with the Code for Seismic Design of Buildings (GB50011-2010), with key indicators including:

1. Seismic displacement angle: This refers to the ratio of inter-story displacement to story height, used to measure structural deformation capacity. The code requires that the displacement angle be controlled within safe limits to prevent structural failure due to excessive deformation.
2. Seismic capacity index: This is assessed by calculating the ratio of internal forces (such as shear and bending moments) under seismic action to the structural bearing capacity, determining whether it meets the design objectives of "no damage under minor earthquakes, repairable under moderate earthquakes, and no collapse under major earthquakes."
3. Period and crack control: The natural vibration period should avoid the site's predominant period to reduce resonance risk; crack control performance is evaluated by observing the width and distribution of cracks in components such as walls and floor slabs after testing, as excessive cracking may affect structural integrity.
4. Displacement limits: The code sets thresholds for inter-story displacement and roof displacement under different seismic fortification intensities, with exceedances indicating insufficient seismic performance.

III. Result Interpretation and Performance Improvement Directions

Test results require a comprehensive analysis of the house's dynamic response, including deformation patterns, crack development, and overall stability. For example, if local collapse or excessive displacement occurs during testing, it indicates inadequate seismic performance; whereas if only minor cracks develop and the structure remains stable, it suggests basic seismic requirements are met.

Furthermore, for prefabricated concrete structures (such as sandwich panel systems), research confirms that technologies like bolt dry connections or viscoelastic dampers can significantly enhance seismic performance. Bolt connections improve the integrity between components, while dampers reduce seismic force transmission through energy dissipation. However, it should be noted that further research on overall seismic performance is still needed, particularly for details such as complex joint connections and long-term durability, which require additional validation.

In summary, seismic tests for prefabricated panel houses enable scientific evaluation of their seismic capacity through ground motion simulation, data collection, and code comparison, providing a basis for structural optimization.