【作者】 蒲奥；

【导师】 李志业；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2007， 硕士

【摘要】 纤维混凝土(Fibre Reinforced Concrete，简称FRC)作为一种新型复合建筑材料，具有优良的物理、力学性能，与普通混凝土相比，其抗拉、抗弯强度及耐磨、耐冲击、耐腐蚀、耐疲劳性、韧性和抗裂、抗爆等性能可得到提高。国外都对其进行了深人的理论研究和广泛的工程实践。但目前国内这方面的研究较少，缺乏完整、可靠的试验数据用于管片的设计，使得其应用受到局限。本文结合“预制纤维混凝土管片的综合研究与应用”课题，分析了纤维混凝土管片强度增强机理和抗开裂作用机理。并通过数值模拟计算，分析了纤维体积掺量与阻裂效果间的线性关系，得出获得增强效果的最小纤维体积掺量。根据该课题的前期研究成果，提出了纤维混凝土盾构管片配合比设计、材料参数和设计指标；对纤维混凝土管片承载力设计方法做了系统研究，进一步完善了纤维混凝土偏心受压斜截面计算方法。通过课题前期纤维混凝土抗早龄期收缩试验和电阻率试验等各项耐久性试验，得出纤维混凝土管片耐久性设计依据和钢纤维掺量的控制标准。本文通过对纤维混凝土管片应用试验研究，证实了纤维混凝土管片内力满足设计承载力要求，并有足够的安全储备；并能明显减少了拼装施工过程中的裂缝。研究结果证实纤维混凝土管片抗开裂等安全性能比普通钢筋混凝土管片具有明显的优势，同时也通过实践应用验证了纤维混凝土管片配合比、材料指标、设计强度及设计参数等各项研究成果的正确性。通过对接头螺栓应力、接缝张开位移、端部应力的量测，分析了纵向、环向接头的力学效应的一些规律、错缝接头对临近环管片应力传递的影响，得到了弯矩传递系数，并以此简化错缝拼装计算模型，并由实测数据验证了弯矩传递系数的合理性。通过模拟千斤顶推力计算，分析现场试验段管片的破坏形态以及开裂的原因，计算结果与现场试验吻合，计算表明钢筋钢纤维混凝土管片能有效控制施工阶段管片的开裂破坏。至此，本文研究结果证实了纤维混凝土管片用于地铁隧道工程是可行的。实际应用中大量的测试数据对设计方法的完善具有一定的指导作用。同时对同类工程也具有一定的指导意义。更多还原

【Abstract】 FRC (Fibre Reinforced Concrete) as a new type of composite building materials has excellent physical and mechanical properties. Compared with ordinary concrete, FRC’s tensile strength, flexural strength, abrasion resistance, impact resistance, corrosion resistance, fatigue resistance, toughness and cracking resistance, antiknock properties can be increased. It has been conducted the deep research and the widespread project practice on overseas. However, the current domestic research in this area is less. Because of lack of complete and reliable test data for the design of the segments, its application was limited.Based on the "precast FRC shield segments of a comprehensive study and application "topics, I analysed FRC shield segments strength enhancing and cracking resistance mechanism. Through numerical simulation, analysed the linear relationship between the volume of steel fiber content and Anti-crack effect and gained the minimum volume of steel fiber content.According to the subject early research results, proposed the FRC shield segments mixing design, material parameters and design parameters, has done the system research about FRC shield segments capacity design methods and further improved the design methods of the FRC ramp section capacity on off-center compression. Through FRC early age anti-shrinkage test and resistivity test etc various durability test, reached FRC shield segments durability design basis and gained the steel fiber content control standards.Based on FRC shield segments application test, FRC shield segments internal forces met the design capacity and had sufficient security reserves, also can significantly reduce the cracks in construction process. The results confirmed FRC shield segments anti-cracking etc safety performance is better than conventional concrete segments. Through the practical application, we verified that FRC shield segments mixing, material index, design strength, design parameters and other research results were correct.Through the stress of bolt on the joint, joint opening displacement, the ends of stress measurement, analysed some laws about longitudinal, toroidal joint mechanical effect and influence of stress transfer about staggered joint to linking segments, gained a moment transfer coefficient. Thereby simplified the staggered linking numerical simulation model and ve?ified the moment transfer coefficient reasonable from the measured data.Through jack thrust simulation, analysed pattern and cause of damaged segments. The simulation results coincided with the field tes and showed FRC shield segments can effectively control cracking damaged in the construction phaseSo far, results of this study confirmed FRC shield segments for the subway tunnel project is feasible. A large number of test data in Practical application will play a certain guiding role to improve the design methods. Meanwhile it also can provide significance guiding for similar projects.更多还原