高强钢筋混凝土预制弧板井壁力学特性分析

Assessment of Mechanical Characteristic for Reinforced Concrete Precast Arc Shaft Lining

对高强钢筋混凝土预制弧板井壁结构的研究表明,实验结果与数值计算结果基本一致。高强钢筋混凝土预制弧板井壁结构具有很高的承载能力,影响其承载能力的主要因素依次为混凝土的强度等级、厚径比和配筋率。在均布荷载作用下,混凝土的强度等级提高10MPa ,极限承载力提高1 2 6MPa。厚径比每增加1% ,极限承载力增加0 85MPa。增大配筋率对提高其极限承载力作用不大,配筋率增大3倍,极限承载力只增加了0 1MPa。

Assessment of mechanical characteristic for reinforced concrete precast arc shaft lining is achieved by experiment and finite element analysis. The finite element results agree well with measurements from laboratory, which validate the calculation model. At the same time, the load carrying capacity of the high strength reinforced concrete precast arc shaft lining is very high. The factors which influence its load carrying capacity are,in turn, the ultimate uniaxial compressive strength of concrete, the ratio of the thickness to the radius and the ratio of the reinforcement to the concrete. Under the load of uniformity,with the strength grade of concrete increases 10 MPa, its load carrying capacity raises 1.26 MPa. The ratio of the thickness to the radius increases 1%, its load carrying capacity raises 0.85 MPa. However,when the ratio of the reinforcement to the concrete is enlarged 3 times, its load carrying capacity increases only 0.1 MPa. Therefore for designing the high and strong reinforced concrete precast arc shaft lining, the ratio of the reinforcement to the concrete needs only to be considered from the structural point of view rather than improving the load carrying capacity.