UHPC薄壁复合结构提升改造混凝土护栏的技术研究及应用

Research and Application of UHPC Thin-wall Composite Structure in Upgrading and Reconstruction of Concrete Guardrail

摘要:

钢筋混凝土护栏是重要的安全防护结构，随着材料劣化及设计标准的提高，大量现有混凝土护栏已不满足现行规范要求，亟须提升改造。为了克服传统护栏改造方式的弊端，提出了一种新型装配式UHPC薄壁复合结构提升既有混凝土护栏防撞能力的改造方案，其中复合结构由UHPC阻裂防溃层和EPS泡沫混凝土能耗层组成，充分结合了UHPC高强、高韧、高耐久特性及EPS泡沫混凝土的吸能效应。通过实车足尺碰撞试验及实际应用，均验证了该方案的可行性和有效性，可供类似护栏提升改造设计参考使用。

Abstract:

Reinforced concrete guardrail is an important safety protection structure. With the deterioration of materials and the raising of design standards, a large number of existing concrete guardrails have not met the requirements of the current norms, and it is in urgent need of upgrading and reconstruction. To overcome the drawbacks of the traditional guardrail reconstruction methods, a new assembled UHPC thin-wall composite structure reconstruction scheme for upgrading the collision capacity of the existing concrete guardrail is proposed, in which the composite structure consists of a UHPC crack-resistance and anti-collapse layer and an EPS foamed concrete energy consumption layer, and fully combines the high strength, high toughness and high durability of UHPC and the energy absorption effect of EPS foamed concrete. The feasibility and effectiveness of the scheme are verified by the full scale crash test and practical application, which can be referred for the upgrading, reconstruction and design of the similar guardrails.