沿海湿热耦合作用下型钢混凝土组合柱劣化机理研究

针对沿海湿热耦合作用下型钢混凝土组合柱劣化严重这一突出工程问题，以该环境下长服役周期型钢混凝土构件破坏机理与性能评价为目标，利用现场采样、细观测试、环境模型建立、力学性能测试和有限元数值分析等研究手段，深入研究沿海高温高湿环境和结构荷载的长效耦合作用，探明该服役条件下型钢混凝土组合柱静、动力性能随时间演化规律。选取沿海高温高湿环境样本和既有长服役周期型钢混凝土结构样本，提炼代表性环境参数、材性参数以及构件几何参数；建立沿海湿热耦合环境模型；标定实验室加速模拟方案并根据方案对型钢混凝土组合柱进行环境加速处理；开展型钢混凝土组合柱劣化后静、动力性能研究。剖析沿海湿热耦合作用下型钢混凝土组合柱的传力特性及破坏模式，构建损伤后型钢混凝土组合柱的基本力学模型；提出适用于该类服役条件下型钢混凝土组合柱的性能评价方法及失效判别准则，并给出考虑沿海湿热耦合作用的型钢混凝土组合柱承载力计算方法。

Aiming at the prominent engineering problem of severe degradation of steel reinforced concrete composite columns under the effect of coastal humidity-heat coupling, in-situ sampling, meso-testing, environmental model building, mechanical property testing, and finite element numerical analysis are used to deeply study the long-term coupling effects of high-temperature and high-humidity environments along the coast. The evolution of static and dynamic performance of steel reinforced concrete composite columns with time under this service condition is proved. And the failure mechanism and performance evaluation of long service life steel reinforced concrete members in this environment are targeted. Samples of coastal high-temperature and high-humidity environment samples and existing long-service period steel reinforced concrete structures were selected to extract representative environmental parameters, material properties parameters, and component geometric parameters. The model of coastal humidity-heat coupling environment is established. According to the calibrated scheme, the steel reinforced concrete composite columns are treated with environmental acceleration. And the static and dynamic properties of steel concrete composite columns after deterioration are studied. This research analyzes the force transmission characteristics and failure modes of steel reinforced concrete composite columns under the effect of humidity and heat coupling along the coast, and constructs the basic mechanical model of steel reinforced concrete composite columns after damage. The performance evaluation method and failure criterion for steel reinforced concrete composite columns suitable for this type of service conditions are proposed, and the calculation method of bearing capacity of steel reinforced concrete composite columns considering humidity and heat coupling effect along the coast is given.