综合管廊钢筋含量估算方法探讨

Estimation Method of Reinforcement Ratio of Urban Utility Tunnel

为在前期更准确、更简洁、更快速地对综合管廊建设成本进行估算,首先统计了广州丘陵台地区明挖法施工的不同舱数的现浇综合管廊的钢筋含量,得出了最佳配筋率的综合管廊横断面为三舱断面。然后,尝试以若干三舱横断面的综合管廊的钢筋含量为样本,采用多元回归拟合出三舱综合管廊标准段含筋率与横断面宽高比、平均覆土深度两个主要影响因素的回归方程,作为同类地区、类似地质条件与土壤种类以及同类施工方法的现浇钢筋混凝土综合管廊项目含筋率估算的参考数据。最后,另选择了5个同地区采用相同开挖方式的综合管廊进行测算,发现使用拟合的含筋率估算公式得出的配筋率与实际计算的配筋率误差值在5%左右。因此,文章提出的含筋率拟合方程在估算指标方面具有一定的参考性。

In order to estimate the construction cost of the urban utility tunnel more accurately, more succinctly and more quickly in the early stage, this paper calculates the steel content of the cast-in-place urban utility tunnel constructed by open-cut method with different numbers of compartments in Guangzhou Hilly area, and obtains that the cross section of the urban utility tunnel with the best reinforcement ratio is the section of three compartments. At the same time, this paper tries to take the steel weight of several three-compartment cross-sectional composite pipe corridors as samples, and uses multiple regression to fit the regression equations of the two main influencing factors of the standard section of three-compartment composite pipe corridors, namely, the ratio of transverse width to height and the average depth of overburden. As the reference data for the estimation of the reinforcement ratio of the cast-in-place reinforced concrete composite pipe gallery project in the same area, similar geological conditions, soil types and construction methods;finally, five samples with the same excavation method in the same area were selected for calculation, and it was found that the error between the actual reinforcement ratio and the estimated reinforcement ratio by the fitting formula in this paper was about 5%. Thus, the fitting equation of the reinforcement ratio proposed in this paper could be a alternative method of the cost estimation in the early stage.