Sandwich pipe (SP) combining high-strength performance and thermal insulation has been considered an effective solution for oil and gas transportation in ultra-deepwater. Strain hardening cementitious composite (SHCC) is well known for its capacity to withstand both tensile load and external hydrostatic pressure. The sandwich pipe considered in the research is constituted of concentric steel pipes with SHCC annular layer. In the present research work, the SHCC was manufactured, and full scale sandwich pipes were assembled. Intact and damaged specimens were submitted to controlled external pressure in a hyperbaric chamber to obtain the collapse and propagation pressures, respectively. Modeling and simulation of the buckle propagation of the SPs were correlated with the experimental results. The results show that sandwich pipe with SHCC core has an excellent structural strength under high external pressure in both intact and damaged conditions. Moreover, the results also show that the interaction between the annular and the inner/outer pipes provides a significant contribution to the buckling resistance under propagation pressure.

结合了高强度性能和隔热性能的三明治管（SP）被认为是超深水中油气运输的有效解决方案。应变硬化水泥复合材料（SHCC）以其承受拉伸载荷和外部静水压力的能力而闻名。研究中考虑的夹层管由带SHCC环形层的同心钢管组成。在本研究工作中，制造了SHCC，并组装了全尺寸的三明治管。将完整和受损的样品置于高压舱中受控的外部压力下，分别获得坍塌和传播压力。SP的屈曲传播的建模和仿真与实验结果相关。结果表明，具有SHCC芯的夹芯管在完整和受损条件下在高外部压力下均具有出色的结构强度。而且，结果还表明，环形管与内/外管之间的相互作用对传播压力下的屈曲阻力起了重要作用。