高原山区小跨径高墩柱薄壁空心墩应用技术研究

结合云南永武高速公路项目建设,对小跨径高墩柱薄壁空心墩应用技术包括特点及难点、施工工艺和应用效果进行了研究。研究结果表明,采用以翻模施工法和塔吊、定型钢模板等成套设备为主要施工支撑体系,地面工作平台、钢筋机械连接和有效控制混凝土浇筑高度相结合的成套施工技术取得了以下效果:大模板定型钢模施工有效解决了施工中容易产生偏心、扭转的现象;翻模施工法最大限度利用了主要起重设备,节约了相关的小型提升设备,与一般2m～3m翻模施工相比,可减少接茬筋50%,缩短工期20%;墩身主钢筋采用机械连接,剥肋滚轧直螺纹接头与常规帮条焊对比平均节约成本30%,每个接头节省施工时间约15min;提高了施工速度,显著降低施工成本,施工安全、质量可靠,经济效益显著。

Application Technology of Small-Span High-Column Thin-Wall Hollow Pier in Plateau Mountain Area

Combining with the construction project of Yong′an-Wuping Expressway in Yunnan province,the paper studies the application technology of small-span high-column thin-wall hollow pier including characteristics,difficulties,construction techniques and application effect.The results show that the application of a set of construction technology that association of ground work platform,reinforced mechanical connection and effective control of concrete casting height with the main supporting system of complete sets of equipment including turnover formwork method,tower crane,set-shaped steel form,etc,obtains the following effect： the construction of big set-shaped steel template effectively solves the phenomena of eccentricity and torsion;the turnover formwork method utilizes the main hoisting equipment farthest,saves related small lifting equipments,therefore the quantity of steel bar decreased by 50% and the construction period is shorted by 20% compared with general 2m～3m turnover formwork construction;main steel bars are mechanically connected,comparing with conventional welding,rib-peeling roll straight-thread joints can save cost by 30% averagely,and each joint save construction time about 15 minutes;it advances the construction speed and reduces the construction cost evidently,meanwhile the construction is safe,the quality is reliable,and the economic benefit is remarkable.