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低品质粉煤灰的开发利用有重大的环保意义和巨大的经济效益,然而当前研究不足严重制约了其在结构混凝土中的应用。通过弯曲疲劳试验,研究了大掺量低品质粉煤灰混凝土的弯曲疲劳寿命;基于双参数的Weibull分布和试验实测数据,建立了实用的双对数的P-S-N疲劳方程,所建立的疲劳方程与试验数据吻合良好。研究结果可为大掺量低品质粉煤灰水泥混凝土路面结构层设计提供依据。 相似文献
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有效提高低品质粉煤灰的利用率具有重大的环保意义和经济效益。本文采用试验方法,对低品质粉煤灰混凝土的基本力学性能包括轴心抗压强度、劈裂抗拉强度、静力受压弹性模量等进行了研究,探讨了适用于中等及轻交通等级公路路面结构层中低品质粉煤灰混凝土的最大掺量。研究结果可为低品质粉煤灰在公路路面结构层中的推广应用提供理论数据。 相似文献
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低品质活性矿物掺合料透水混凝土试验研究 总被引:2,自引:0,他引:2
通过试验研究了低品质活性矿物掺合料透水混凝土的基本性能,包括单掺低品质硅灰、单掺低品质粉煤灰、双掺低品质硅灰和粉煤灰。宏观上测试了抗压强度、抗折强度、孔隙率和透水系数;微观上用SEM观测了胶结层的微观结构、用EDS观测了胶结层的化学组成。试验结果表明:在普通透水混凝土中掺入一定量的低品质活性矿物掺合料替代部分水泥是可行的;单掺低品质硅灰效果最佳、掺量可在6%左右单掺低品质粉煤灰次之、掺量可在15%左右;单掺低品质硅灰透水混凝土和单掺低品质粉煤灰透水混凝土强度等级为C15左右,孔隙率均不低于20%,透水系数均不低于20×10~(-2)cm/s,可以满足一般轻交通路面的应用条件。 相似文献
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粉煤灰路面高强混凝土抗渗性能试验研究 总被引:1,自引:0,他引:1
通过试验,研究大掺量粉煤灰路面高强混凝土的抗渗性能,研究结果表明:粉煤灰的掺入可以有效降低路面高强混凝土的相对渗透系数,从而使混凝土的抗渗透能力得到明显的提高,研究结果可为大掺量粉煤灰推广应用于路面工程提供参考。 相似文献
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大掺量低质粉煤灰配制中高强度混凝土试验研究 总被引:3,自引:0,他引:3
大量低品质粉煤灰在混凝土中的应用,是减轻燃煤废料污染、缓解矿物能源危机的有效途径。试验用较低品质粉煤灰配制中高强度混凝土,比较了粉煤灰品质、掺量,水胶比和胶凝材料总量对混凝土抗压强度的影响,认为水胶比和粉煤灰掺量对混凝土强度起主要作用。在低水胶比前提下。粉煤灰品质的影响不大。 相似文献
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大掺量低质粉煤灰配制中高强度混凝土 总被引:1,自引:0,他引:1
大量低品质粉煤灰在混凝土中的应用,是减轻燃煤废料污染、缓解矿物能源危机的有效途径。本文试验用较低品质粉煤灰配制中高强度混凝土,比较了粉煤灰品质、掺量,水胶比和胶凝材料总量对混凝土抗压强度的影响。认为水胶比和粉煤灰掺量对混凝土强度起主要作用,在低水胶比前提下,粉煤灰品质的影响不大。 相似文献
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通过水泥混凝土拌合物性能试验,硬化水泥混凝土力学试验及元江-东峨农村公路路面改建工程实践,在相同等级水灰比不变的情况下,对掺有3种不同粗集料的水泥混凝土进行了对比分析,得出破碎卵石水泥混凝土路面具有良好经济效益,值得推广的结论。 相似文献
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从山区混凝土路面施工的实际出发,研究了山区公路路面早期裂缝的产生机理,通过调整混凝土水灰比、泵送剂掺量、砂率、坍落度等环节,提出了一条切实可行的混凝土工艺,以有效地提高山区混凝土路面的早期抗裂性。 相似文献
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ZHU Jinying 《结构工程师》2011,27(Z1):313-319
Elastic wave-based non-destructive testing(NDT) methods are effective for flaw detection in concrete structures and pavements.However,the test speed of elastic wave-based methods is severely limited by the physical coupling between sensors and concrete surface.The air-coupled sensing method is proposed as a solution to develop rapid NDT techniques for concrete infrastructure.This paper reviews the development of air-coupled sensing technique for concrete structures in civil engineering applications.It pr... 相似文献
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钢纤维混凝土在路面桥面工程中应用 总被引:10,自引:0,他引:10
钢纤维混凝土是一种新型的复合材料 ,具有优良的抗裂性、抗弯性、耐冲击性、耐疲劳性等特点 ,在公路路面、桥面、机场跑道等工程中应用表明 ,钢纤维混凝土具有减薄面层厚度、加大缩缝间距、改善路面的使用性能、延长路面使用寿命等优点。对钢纤维混凝土路面的经济性应从长期和短期效益 ,一次投入与维修保养费用等进行综合合理评定 ,以便更好地推广应用钢纤维混凝土路面。 相似文献
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Sunghwan KIM Halil CEYLAN Kasthurirangan GOPALAKRISHNAN 《Frontiers of Structural and Civil Engineering》2014,8(2):101-114
In this study, finite element (FE)-based primary pavement response models are employed for investigating the early-age deformation characteristics of jointed plain concrete pavements (JPCP) under environmental effects. The FE-based ISLAB (two-and-one-half-dimensional) and EverFE (three-dimensional) software were used to conduct the response analysis. Sensitivity analyses of input parameters used in ISLAB and EverFE were conducted based on field and laboratory test data collected from instrumented pavements on highway US-34 near Burlington, Iowa. Based on the combination of input parameters and equivalent temperatures established from preliminary studies, FE analyses were performed and compared with the field measurements. Comparisons between field measured and computed deformations showed that both FE programs could produce reasonably accurate estimates of actual slab deformations due to environmental effects using the equivalent temperature difference concept. 相似文献
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《Construction and Building Materials》2000,14(3):171-176
Deterioration to concrete structures usually starts at the surface and progresses into the structure. The deteriorated concrete has to be removed and replaced by new repair material, which leads to a composite concrete/repair material structure. In order to ensure full structural interaction between the old and new material, it is necessary to have a good bond between them. The bond itself depends on having a clean and rough surface. The importance of surface preparation and the effect of roughness have been emphasised by many researchers. In order to study the effect of surface roughness on the bond between a repair material and the concrete substrate, the roughness of the surface needs to be measured. No standard method for measuring surface roughness of concrete has been adopted. A range of methods are available and are in use for measuring the surface texture of concrete pavements in the highway field, but no method is accepted as standard. A new method of quantifying surface roughness is proposed and compared with the only method reported in the literature. In this new method (referred to as the roughness gradient method) a new method of describing the surface roughness is proposed. The surface of the cut concrete is defined as a series of irregular waves. The roughness parameter is dependent on the peak-to-trough depth and the respective wavelength. The method adopted using the ‘roughness gradient’ (R.G.) gave a better indication of the treated surfaces used in testing concrete repairs. Visual observation of the treated surfaces seemed to be in agreement with the R.G. parameters, while the method reported in the literature failed to define the roughness of the surface of the whole substrate in an accurate and comprehensive way. 相似文献
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对某农村水泥混凝土路面破坏进行了现场调查,分析了路面严重破坏的主要原因,并提出了农村水泥混凝土路面破坏预防措施,从而提高农村公路建设和管理水平。 相似文献
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对县乡公路水泥混凝土路面发展现状进行了简要介绍,分析了目前县乡水泥混凝土路面施工难点及存在的问题,探讨了相应对策,并提出建议,以保证县乡公路水泥混凝土路面施工技术的安全和质量。 相似文献