PHC桩损伤处应力释放与水平受力影响分析

Analysis of stress release and horizontal stress at damage of PHC pile

基于大型有限元软件ANSYS建立单桩有限元模型,以某5万DWT高桩码头为例,计算分析PHC桩在桩基完整性检测割桩处的应力释放以及损伤对水平承载的影响。结果表明:PHC桩在割桩损伤处应力释放明显,损伤区域应力变化剧烈,损伤处应力变化规律和应力集中系数与桩的预应力水平无关;水平荷载作用时PHC桩的预应力对于提高损伤桩的抗裂效果明显,损伤处受应力集中影响,预应力水平越高损伤处应力变化越大,而且最不利应力位置也下移到损伤平台内侧处。

With the large finite element software ANSYS, this paper establishes the single pile finite element model based on a 50 000 DWT high pile wharf.Calculation and analysis of the stress release at the damage and the influence of the damage on the horizontal bearing capacity in pile integrity detection in PHC pile are done. The results show that the stress release of PHC pile at the damage is obvious, the stress change at the damaged is significant, the rule of the stress change and the stress concentration factor are not related to the stress level of the pile.The pre-stress in PHC pile can improve the ability of cracking resistance of the damaged pile greatly. Stress concentration is significant at the damage, when the pre-stress level is higher, the stress change is greater at the damage.The most unfavorable section moves to platform damage.