Optimizing the seismic performance of corrugated container houses requires a comprehensive approach encompassing multiple dimensions, including the structural system, connection method, and foundation design. The key lies in improving overall stiffness coordination, energy dissipation capacity, and the stability of force transmission paths through scientific design and construction measures. As modular buildings, corrugated container houses utilize standard containers as their units. Optimizing their seismic performance requires transcending the limitations of a single container and constructing a holistic structural system where multiple containers coordinate forces.
First, the connection nodes between containers are crucial for seismic design. Traditional corrugated container houses rely on bolted corner connections, but these connections are prone to loosening and stress concentration under earthquakes. Optimization solutions include the use of seismic-absorbing connection nodes. By adding lead viscoelastic dampers, shear connectors, and beam end reinforcements, a "rigid and flexible" connection structure is achieved. This design maintains high stiffness under vertical loads. During an earthquake, the dampers enter an energy-dissipating phase, reducing joint stiffness to mitigate internal forces and prevent container dislocation or separation. At the same time, butt beams or steel supports are installed between adjacent boxes to form a transversely rigid frame, suppressing torsional effects caused by unilateral forces.
Secondly, the overall structure needs to establish a multi-path force transmission mechanism. Single boxes are prone to local buckling during earthquakes due to their large spans and lack of restraint. Therefore, lateral stiffness must be enhanced through diagonal bracing, bracing, or small shear walls. For example, cross bracing can be added inside or outside the box to distribute horizontal forces across multiple transmission paths, preventing overloading of a single component. For multi-story structures, horizontal displacement coordination must be achieved to prevent individual boxes from becoming "islands" due to load differences. Furthermore, the enclosure structure should utilize corrugated sheeting or lightweight composite panels, creating a skin effect with the box frame. This provides lateral restraint through in-plane tensile and compressive strength, thereby enhancing overall lateral stiffness.
Foundation design directly impacts seismic performance. During an earthquake, the coordinated operation of the foundation and superstructure is crucial. Steel pipe piles, reinforced concrete caps, or mixed foundations are recommended to ensure effective transmission of horizontal forces into the subsurface. Rigid or semi-rigid anchoring is required between the foundation and the container to prevent amplified container displacement due to foundation slip during an earthquake. In areas with complex geological conditions, foundation reinforcement, such as replacing solidified soil or adding anti-floating anchors, is necessary to prevent structural damage caused by uneven settlement.
Optimizing the layout can reduce the risk of torsion. The floor plan of a corrugated container house should be as symmetrical as possible, avoiding excessive length-to-width ratios or significant unevenness. If site constraints necessitate an asymmetrical layout, a central axis design or additional vertical supports should be used to offset torque transmission. Furthermore, door and window openings should be located away from structural weaknesses to prevent stress concentrations caused by localized weakening of rigidity. For example, intermediate supports can be installed in long-span areas, or short-span composite structures can be used to distribute seismic forces.
Materials and construction details are equally critical. High-strength steel can increase component load-bearing capacity, while lightweight composite materials can reduce top inertia forces and mitigate seismic response. The quality of connectors directly impacts seismic reliability. High-strength bolts and qualified weld processes should be used, and on-site verification should ensure that parameters such as bolt torque and weld length meet design requirements. Furthermore, the design must include anti-corrosion treatment of the enclosure surface and the weather resistance of the enclosure materials to prevent a decrease in rigidity due to rust.
Finally, dynamic assessment and long-term maintenance are essential. In addition to empirical design, structural assessments using methods such as time-history analysis and seismic response spectrum analysis are necessary to ensure that deformation and internal force distribution under the design earthquake intensity remain within safe limits. During operation, regular inspections for loose bolts and worn connections are necessary, and aging components should be replaced promptly. For existing buildings, seismic upgrades can be implemented by adding dampers and reinforcing connection points to extend the life of the structure.
