【作者】 王珺；

【导师】 张宏博； 宋修广；

【作者基本信息】 山东大学 ， 交通运输（专业学位）， 2024， 硕士

【摘要】 随着全域旅游理念的兴起和旅游公路建设的快速发展,道路排水、绿化以及边坡防护支挡等工程内容成为设计关键要素,有效的雨水管理、路面积水防控、水土保持以及促进生态平衡变得更加重要,这同时也提高了对高效透水材料的技术需求。然而,传统透水材料如透水混凝土和透水砖面临成本高、自重大、维修困难等技术难点,且对地基承载力具有较高的要求,总体造价偏高。基于此,本文提出了一种新型透水泡沫混凝土(PFC)材料的研发与制备方法,该材料综合了泡沫混凝土的轻质、密度可调等特点,通过改变材料组成和孔隙结构,赋予了其良好的透水透气及保水释水功能,为旅游公路及市政道路建设提供了一种经济、高效的新型排水材料。为明确其材料组成,验证应用效果及耐久性,本文针对PFC材料开展了全交及正交配比试验,探讨了其力学性能、透水性能及微观结构,推荐了基于不同应用场景的材料组成设计方法;并进一步开展了涵盖水稳定性、抗冻融循环以及疲劳加载特性的耐久性试验研究,验证了其长期稳定性。根据研究成果,提出如下主要研究结论:(1)研究提出了透水型泡沫混凝土的制备工艺,通过采用四因素四水平的正交试验,明确了水固比、细砂掺量、纤维掺量、吸水树脂掺量对PFC抗压强度、抗折强度、渗透系数和孔隙率的影响程度次序,得到了不同试验指标下材料的优选配合比。(2)基于单因素试验分析,探讨了上述各因素对PFC力学性能和透水性能的影响规律及影响机理,结果表明水固比(0.28～0.4)对二者的影响呈现先升后降的抛物线趋势,吸水树脂的增加会提高材料透水性,降低其强度;细砂和纤维亦可适当提高材料的强度和透水性,但掺量不宜超过本文推荐上限。(3)光学显微镜及SEM微观结构测试表明,透水型泡沫混凝土透水性主要受控于其孔隙结构尺寸、连通性及细砂与纤维对泡孔的破坏连通作用,其中吸水树脂发挥了主要造孔及内养护的作用,细砂及纤维则起到导水作用;PFC强度主要来源于水泥水化产物及完整胞壁结构,但料浆湿密度不宜过低。(4)根据不同应用场景的工程需求分析,研究提出了 PFC材料组成设计方法及最佳平衡配比。并基于多元回归分析,建立了 PFC抗压强度与渗透系数/孔隙率、渗透系数与孔隙率,以及抗压强度、渗透系数与各试验因素之间的回归预测模型,可用于简化后续配合比设计工作。(5)选定三类不同应用场景的PFC代表性配比试件,开展了水稳定性、抗冻融循环及疲劳动载破坏等耐久性试验。结果表明,所有试件均具有良好的水稳定性和抗冻融性,可满足正常工作环境需求;但对于强透水性PFC材料,其耐疲劳特性较弱,建议用作无疲劳荷载作用的场景。更多还原

【Abstract】 With the emergence of the all-domain tourism concept and the rapid development of tourism road construction,engineering aspects such as road drainage,landscaping,and slope protection barriers have become key elements in design.Effective stormwater management,prevention of road surface water accumulation,soil conservation,and promotion of ecological balance have become increasingly crucial.This has also heightened the technical demand for efficient permeable materials.However,traditional permeable materials such as pervious concrete and permeable bricks face challenges including high costs,significant weight,maintenance difficulties,and high foundational load requirements,generally resulting in higher overall costs.Against this backdrop,this paper introduces a novel development and preparation method for Permeable Foamed Concrete(PFC),a material that integrates the lightweight and adjustable density characteristics of foamed concrete.By modifying the material composition and pore structure,it imparts good permeability,air permeability,and water retention and release functions,offering an economical and efficient new drainage material for tourism road and municipal road construction.To clarify its composition and verify its application effects and durability,this study conducted full factorial and orthogonal experiments on the PFC material,exploring its mechanical properties,permeability,and microstructure,and recommended material composition design methods for different application scenarios.Further,durability tests covering water stability,freeze-thaw cycles,and fatigue characteristics were conducted to verify its long-term stability.Based on the research findings,the following main conclusions are presented:(1)This paper introduced the preparation process for permeable foamed concrete,employing a four-factor four-level orthogonal experiment to ascertain the sequence of impact of water-to-solid ratio,fine sand content,fiber content,and water-absorbing resin content on the compressive strength,flexural strength,permeability coefficient,and porosity of PFC,thereby obtaining the optimal mix proportions for different experimental indicators.(2)Based on single-factor experimental analysis,this study explored the patterns and mechanisms by which various factors affect the mechanical and permeable properties of Permeable Foamed Concrete(PFC).The results indicated that the water-to-solid ratio(0.28～0.4)impacts both properties in a parabolic trend,initially increasing and then decreasing.Additionally,the inclusion of water-absorbing resin was found to enhance the material’s permeability while reducing its strength.The use of fine sand and fibers can also appropriately increase both the strength and permeability of the material,though their proportions should not exceed the upper limits recommended in this paper.(3)Optical microscopy and Scanning Electron Microscopy(SEM)tests of the microstructure revealed that the permeability of Permeable Foamed Concrete(PFC)is primarily governed by the size and connectivity of its pore structure,and the disruptive connectivity effect of fine sand and fibers on the foam pores.Water-absorbing resin plays a crucial role in pore formation and internal curing,while fine sand and fibers facilitate water conduction.The strength of PFC mainly derives from the hydration products of cement and the integrity of the cell wall structure,although the wet density should not be excessively low.(4)Based on the study of different application scenarios,an optimized design method for the composition of PFC materials and the best balance mix ratio were proposed.Using multiple regression analysis,predictive regression models were established for the relationships between PFC compressive strength and permeability coefficient/porosity,permeability coefficient and porosity,as well as compressive strength,permeability coefficient,and various experimental factors,which can be used to simplify the workload of subsequent mix design.(5)Representative mix proportions for Permeable Foamed Concrete(PFC)were selected for three different application scenarios and subjected to durability tests,including water stability,freeze-thaw cycles,and fatigue dynamic loading.The results indicated that all specimens exhibited good water stability and freeze-thaw resistance,meeting the requirements of normal operating environments.However,the materials with strong permeability characteristics showed weaker fatigue resistance,suggesting their suitability for applications without fatigue loading impacts.更多还原