高韧性混凝土组合桥面铺装层间应力简化计算方法

Simplified Calculation Methods for Interlayer Stress of STC Composite Bridge Deck Pavement

为研究高韧性混凝土组合桥面铺装层间应力简化计算方法,采用ANSYS有限元分析,探讨钢-STC-SMA结构厚度、环境温度、桥面纵坡等对层间应力的影响规律,建立轻型组合桥面铺装层间应力估算模型,提出层间最大剪应力、最大法向拉应力简化计算公式.研究结果表明:SMA厚度、STC厚度、环境温度、桥面纵坡等对层间应力有不同程度的影响;在最不利荷载组合下,不计桥面纵坡时,层间最大剪应力变化范围为0.38~0.55 MPa(常温)、0.35~0.55 MPa(高温);层间最大法向拉应力变化范围为0.18~0.23 MPa;层间应力随着桥面纵坡的增加而线性增加,纵坡从0%增加到8%,层间最大剪应力升幅为9.4%(常温)、12.0%(高温),层间最大拉应力升幅为12.0%(常温)、12.5%(高温);通过纵坡坡度修正,建立高韧性混凝土组合桥面铺装层间应力通用计算公式,并与实桥有限元计算结果对比,误差在9%以内,说明本文提出的计算方法可用于估算不同纵坡下高韧性混凝土组合桥面铺装层间应力.

In order to study the simplified calculation methods of interlayer stresses for Super Toughness Concrete(STC)composite bridge deck pavement,finite element analysis was carried out by ANSYS software.The influence laws of steel-STC-SMA structure thickness,ambient temperature,and longitudinal slope on interlayer stress were discussed.The stress estimation models for STC composite bridge deck pavement were established.The simplified calculation formula of maximum shear stress and maximum normal tensile stress between layers were presented.The results show that the interlayer stresses are influenced by some factors such as the thickness of SMA and STC,environmental temperature,and longitudinal slope.Under the most unfavorable load combination,the maximum interlayer shear stress variation range is 0.38~0.55 MPa(normal temperature)or 0.35~0.55 MPa(high temperature),and the maximum normal tensile stress ranges from 0.18 to 0.23 MPa,when the deck longitudinal slope is not taken into account.The interlayer stress increases linearly with the increase of the longitudinal slope of the bridge deck.If the longitudinal slope increases from 0%to 8%,the maximum layer shear stress is increased by 9.4%(normal temperature)or 12.0%(high temperature),and tensile stress by 12.0%(normal temperature)or 12.5%(high temperature).The general calculation formula of stress between deck pavement layers of the STC composite bridge is established by modifying the longitudinal slope degree.Compared with the finite element calculations of a real bridge,the error is less than 9%,indicating that the methods proposed in this paper can be used to estimate the interlayer stress of STC composite bridge deck under different longitudinal slopes.