预制T梁混凝土浇筑振捣质量关键控制措施

Key Quality Control Measures of Prefabricated Concrete T-Beam Pouring and Vibrating

为有效避免因浇筑振捣不当导致预制T梁混凝土出现内部缺陷及表观质量等问题,文章依托云南某高速公路预制混凝土T梁质量提升专项行动,对混凝土浇筑过程中各布料工艺的优缺点进行对比分析,并对振捣工艺中的关键质量控制措施进行梳理。结果表明:纵向单隔板分段水平分层布料工艺因兼具斜向和整体分层布料的优点,在综合考虑浇筑质量及工效的基础上,推荐其在预制混凝土T梁浇筑中使用;为保证梁体两侧模板附着式振捣器的有效振捣,振捣器应分两排呈等腰三角形交错布设,其纵向及垂直间距建议值分别为140cm~150cm和50cm~60cm;在梁体浇筑过程中,附着式振捣器应做到有序开启,振捣适中,严禁出现空振、早振、欠振及过振。研究可为制备高品质预制混凝土T梁提供参考。

In order to effectively avoid internal defects and apparent quality problems of prefabricated concrete T-beam caused by improper pouring and vibrating, relying on a special action to improve the quality of prefabricated concrete T-beam in a certain expressway project in Yunnan province, the advantages and disadvantages of various distribution technologies during the pouring process and the key quality control measures in the vibration process are analyzed. The results show that the longitudinal single diaphragm segmented horizontal layered distribution technology has the advantages of both diagonal and overall layered distributing, and it is recommended to be used when prefabricated concrete T-beam is poured based on comprehensive consideration of the quality and efficiency of the pouring. In order to ensure the effective vibration of the attached vibrators arranged on the template on both sides of the beam, the vibrators should be arranged in two rows in an isosceles triangle staggered arrangement. The recommended values of longitudinal and vertical spacing are 140cm~150cm and 50cm~60cm respectively. During the whole casting process, the attached vibrator should be opened in an orderly manner, and the vibration should be moderate. Empty vibration, early vibration, under-vibration and over-vibration are not allowed. The conclusions would provide a useful reference for the preparation of high-quality prefabricated concrete T-beams in the future.