Earthquake Test of Prefabricated Panel Houses

Earthquake tests on prefabricated panel houses indicate that their seismic resistance is significantly influenced by design standards, construction quality, and reinforcement measures. Typically, they can withstand earthquake intensities of magnitude 6-7, but older buildings or those with damage exhibit poorer seismic performance.

I. Basic Standards for Seismic Resistance

According to national regulations, the seismic resistance of prefabricated panel houses generally corresponds to earthquake intensities of magnitude 6-7 (approximately magnitude 6 on the Richter scale), with some stringent regions (such as Beijing) reaching an intensity of 7 degrees (magnitude 7). However, there are significant variations in these standards: prefabricated panel houses built before the 1980s may only have a seismic intensity of 6 degrees, while recently constructed buildings can be upgraded to 7 degrees through structural optimization. For example, Beijing stipulates that prefabricated panel residential buildings can be constructed up to 14 stories, but in practice, they are often limited to 12 stories or fewer to ensure safety.

II. Key Factors Affecting Seismic Performance

1. Design and Construction Quality
   Structural design must strictly adhere to regulations, with details such as the treatment of joints between prefabricated panels and steel bar connections directly impacting structural stability. If construction does not follow stacking layer limits or if there are defects in jointing techniques, seismic resistance may be compromised.
2. Building Materials and Construction
   The standard load-bearing capacity of prefabricated panels is 200 kg/㎡, with special designs capable of reaching 450 kg/㎡. However, excessive load-bearing reduces seismic redundancy. Brick-concrete structured prefabricated panel houses exhibit significantly lower seismic performance compared to frame-structured or shear-wall structured buildings due to the brittleness of their walls.
3. Foundation and Building Height
   Low-rise buildings (below 6 stories) demonstrate better seismic performance than high-rise buildings due to their lower center of gravity and smaller sway amplitude. Foundation depth and reinforcement measures (such as deepening foundations and adding pile foundations) can significantly enhance overall stability.

III. Seismic Issues in Actual Cases

Inspection data on older buildings shows that under the same earthquake magnitude and external conditions, the probability of damage to prefabricated panel residential buildings is generally higher than that of cast-in-place brick-concrete and frame-structured buildings. For example, prefabricated panel houses classified as Grade C may experience structural disintegration during a magnitude 5 earthquake; during the 2008 Wenchuan earthquake, some prefabricated panel buildings collapsed due to failure at connection nodes.

IV. Effectiveness of Seismic Reinforcement Measures

Seismic resistance can be significantly enhanced through structural reinforcement (such as adding steel frames and pouring concrete joints), wall treatment (thickening exterior walls and adding lateral supports), and seismic isolation technology (installing seismic isolation bearings). For example, steel frame reinforcement can enhance overall rigidity, while seismic isolation bearings can absorb 30%-50% of earthquake energy, enabling buildings to maintain functionality during strong earthquakes.