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水泥混凝土路面耐久性评价方法研究

Research on Durability Evaluation Method of Cement Concrete Pavement

【作者】 安丰伟

【导师】 张擎;

【作者基本信息】 长安大学 , 道路与铁道工程, 2011, 硕士

【摘要】 目前水泥混凝土路面早期病害严重,由路面耐久性不足引发的病害严重制约了水泥路面的发展。但现有的水泥路面耐久性评价体系不够完善,不能满足水泥路面发展的要求,迫切需要一种完善的评价体系对路面进行评价,为路面提供设计、养护、维修等参考依据。为完善路面的评价体系,本文从路面裂缝、断板、脱空、错台等几种典型病害引起的路面耐久性不足出发,分析病害的产生机理和影响因素;从路面组成材料和结构两方面,提出耐久性评价指标,建立水泥混凝土路面耐久性评价体系。本文提出断裂韧性、弯拉强度和基层材料冲刷系数作为材料耐荷性评价指标。通过二次正交回归实验分析得出符合耐久性的耐荷性指标和材料配合比设计建议值。耐候性方面,研究得出含气量是控制材料抗冻和抗盐冻剥蚀性能的主要因子,将含气量作为抗冻耐久性的控制指标,同时给出了满足耐候性的路面材料含气量取值范围。结构耐久性方面,以脱空半径为板底脱空的评价指标,优化了冲刷脱空预估模型,按照板底脱空半径对路面损坏状况进行了分级;路面错台以错台量为评价指标,分析半刚性基层错台产生机理,对错台量进行了预估,建立了错台量、标准轴载作用次数和冲刷系数之间的关系;接缝传荷方面,传力杆松动是传荷能力衰减的直接原因,提出考虑松动量的接缝传荷能力计算公式,通过控制传力杆直径和地基模量来降低传荷能力的衰减;针对刚性基层路面温度翘曲作用下产生开裂状况严重程度,分析了板厚、温度梯度、基层模量对面板工作性能的影响,提出用板厚和基层模量来控制温度翘曲,来提高路面的耐久性。综合以上分析,系统提出了路面耐久性评价体系和评价流程。最后本文从材料组成、配合比和结构设计方面,提出了提高水泥耐久性的措施。

【Abstract】 The early disease of cement concrete pavement is serious at present, the disease caused by the road of insufficient durability has seriously restricted the development of the cement pavement. But the existing evaluation system of durability of concrete pavement is not perfect, can not meet the needs of the development of cement pavement. Therefore a perfect evaluation system for pavement is urgent need, to provide a reference for pavement design, maintenance and rehabilitation. To improve the road evaluation system, this paper based on several typical diseases caused by insufficient durability roads, such as cracks, broken plates, disengaging, dislocation, analyzed the generation mechanism of pavement disease and influencing factors; from the perspective of road material and structure composition, proposed evaluation index of concrete durability, and established the durability evaluation system of the concrete pavement.In this paper, fracture toughness, flexural-tensile strength and the index of the anti-scour ability of the base course are proposed as the evaluation index of the load-resistant performance. Through quadratic regression testing design and laboratory experiment, concludes the suggested value the index of the load-resistant performance and the optimum mixture ratio of cement concrete to meet the durability requirements. In the perspective of weathering resistance, obtained a result that air content is the main factor of the control of the performance of material frost-resistance and the deicer -scaling resistance, selected air control as the control parameter of the durability of concrete. As the same time, the range of pavement materials air content was given to meet the weathering resistance.In the perspective of Structural durability, Radius of the cavity was proposed as the index of the cavity beneath slab, and the prediction model of the erosion and cavity beneath slab was simplified, and the pavement condition classification was divided according the radius of cavity beneath slab; the amount of the faulting was selected as the index of faulting, the amount of the faulting was predicted and the relation was established among the amount of the faulting, the number of standard axle loads and the anti-scour coefficient; aspect of joint load-transfer, dowel bars’looseness is the immediate cause of the attenuation of load transfer, and the calculation formula of load transfer ability was proposed which considers the amount of looseness, and it can reduce the attenuation of joint load-transfer capacity by control the dowel bar diameter and the foundation modulus; according to condition that the influence of temperature warping was serious, analyzed the influences of thickness, temperature gradient, the base modulus to the workability of the panel and proposed using the thickness of the panel and base modulus to control the temperature warping and improve the durability of the concrete pavement.Synthesizes the above analysis, in this paper, Making a systematic suggestion for the concrete durability evaluation system and the process of comprehensive evaluation. At last, from the perspective of the material composition, mixture ratio and structure design, several advices and measures were proposed to improve the durability of cement concrete pavement.

  • 【网络出版投稿人】 长安大学
  • 【网络出版年期】2012年 01期
  • 【分类号】U416.216
  • 【被引频次】3
  • 【下载频次】366
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