滑模施工混凝土筒仓结构的缺陷原因分析

Defect Causes Analysis for the Reinforced Concrete Silo Formed on Slipforming Construction

混凝土筒仓采用滑模施工相对简便快捷,模板投资较低,可连续作业,该施工方法普遍用于混凝土烟囱、冷却塔、广播电视发射塔等高耸体形且截面规则壳体结构的浇注成型,多年来,作为专项成套技术在国内外得到了广泛应用。近年的国内工程调查表明,滑模施工混凝土筒仓的筒壳易出现以下缺陷:表层强度不同程度低于内部及设计强度,混凝土粘结握裹配筋状况较差,不规则与环向水平裂缝,对结构各项性能有明显不利影响。为此,对混凝土筒仓因滑模施工可能导致质量劣化的问题进行了分析研究,提出了相关技术建议,可供结构设计与施工人员参考。

For the slipforming construction to built reinforced concrete silos, it is not only faster and easier relatively than that in usual, but also less template investment and it brings about continuous operation. The method is still widely used to built this kind of tall and regular cross-section concrete shells, such as chimneys, cooling towers, radio and TV towers etc. and it is token as special sets of construction technology at home and abroad for many years. In recent years, a number of engineering surveys in the domestic showed that the following shell defects appeared easily in slipforming construction and affected them badly, such as surface concrete strength which was less generally than that of the internal and the design requirement, poor concrete adhesive around reinforcements, more irregular and annular cracks on silo walls. To resolve these problems, careful analysis and research are done for the quality deterioration of reinforced concrete silos due to slipforming techniques, and then some improved suggestions are proposed to the reference for relative structural designers and workers.