水泥基复合半刚性面层材料热应力分析

根据水泥基复事半刚性面层材料（ＣＢＳＣＣ）的微结构，建立了将裹橡胶沥青组集料颗球和水泥砂浆空心基体球嵌入ＣＢＳＣＣ等效复合材料介质中的三层嵌套模型，推导了热应力计算公式，计算结果表明，ＣＢＳＣＣ的切向拉应力和径向拉应力比水泥混凝土的对应值小，抗裂能力提高，讨论了进一步提高ＣＢＳＣＣ抗温缩开裂能力的途径。     

碱矿水泥砂浆的碱集料反应膨胀研究

通过测长试验,研究了三类碱矿渣水泥（ＡＡＳＣ）砂浆的碱集料反应（ＡＡＲ）引起的膨胀,分析了碱组分种类、碱质量分数、活性集料质量分数和矿种类等因素对ＡＡＳＣ砂浆ＡＡＲ膨胀率的影响,综合宏观和微观测试结果,探讨了碱矿渣混凝土的碱集料反应机理,结果表明,ＡＡＳＣ系统出现危险性碱集料反应的可能性远低于普通水泥系统 。     

炭纤维干混水泥及其力学性能研究

短切沥青基炭纤维和水泥，在自制混合器中混合１０ｍｉｎ，在纤维长度小于６ｍｍ，重量含量小于２％的情况下均可得到炭纤维分散非常均匀的炭纤维干混水泥（ＣＣＰＭ）。用ＣＣＰＭ可制备具有较好力学性能的新型复合材料──炭纤维增强水泥（ＣＦＲＣｅ）。在实验的基础上，分析了影响ＣＦＲＣｅ力学性能的各因素，并探讨了炭纤维增强、增韧机理和复合材料的失效方式。     

水性环氧树脂乳化沥青复合材料与集料粘结强度研究

为研究水性环氧树脂乳化沥青符合材料与集料的粘结性能,采用数显全自动拉脱法附着力测试仪测定了不同水性环氧掺量下,复合材料与石料基材的粘结强度,并基于粘结强度,评价了水性环氧树脂乳化沥青与集料的粘结强度,推荐了复合材料中水性环氧树脂的合理掺量。研究结果表明,水性环氧树脂和固化剂的加入,有效增加了胶结材料与集料的粘结性能,且水性环氧树脂乳化沥青符合材料中水性环氧树脂掺量约在30%～50%为宜。     

一种可吸收汽车尾气的橡胶沥青排水路面混合料

正授权公告号:CN 103332904B授权公告日:2015年10月7日专利权人:河海大学发明人:于新、姚城熙、彭刚等本发明公开了一种可吸收汽车尾气的橡胶沥青排水路面混合料。混合料配方为:橡胶沥青3~10,集料100,外掺剂1~3。集料为玄武岩,外掺剂为水泥和光触媒混合物(水泥1~2,光触媒1~2),光触媒主要成分为锐钛矿型纳米二氧化钛。本发明充分利用橡胶沥青     

乳化沥青水泥复合材料压力灌浆技术的应用

乳化沥青在道路工程中的应用是非常常见的,而水泥则是水泥混凝土材料的重要组成材料,是道路工程必不可少的工程材料,水泥的刚性加之乳化沥青的柔性,再辅之一定的灌浆技术,必将会有较大的应用前景。目前的研究主要是在水泥材料中添加乳化沥青形成乳化沥青水泥复合材料,来改变它的某些性能,已出现了较多有价值的研究成果及工程应用。     

定向短纤维弹性体复合材料围油栏的研制

介绍了以尼龙６短纤维为骨架材料,以ＣＲ／ＮＢＲ并用体系为主体材料的定向短纤维弹性体复合材料（ＯＳＦＥＣ）围油栏的研制。ＯＳＦＥＣ配方确定为：ＣＲ９０;ＮＢＲ１０;尼龙６短纤维４０;炭黑Ｎ２２０２０;炭黑Ｎ６６０２０;硫化剂９;粘合剂ＲＡ／ＲＳ／白炭黑２０５;增塑剂１６;促进剂１;防老剂１５。其中尼龙６短纤维用异氰酸酯溶液预处理效果较好。ＯＳＦＥＣ围油栏与织物芯橡胶型围油栏相比物理性能和使用性能好、生产成本低。     

可再分散乳化沥青粉末改性水泥砂浆的力学性能和微观形貌

为解决水泥基材料脆性大、韧性差问题,本文提出了掺加可再分散乳化沥青粉末（REAP）以改善水泥基材料韧性的方法。试验制备了REAP 掺量为胶凝材料用量0、10%、20%、30%的可再分散乳化沥青颗粒改性水泥砂浆（REAPMCM）,研究了REAP对REAPMCM抗压、抗折强度、折压比、弹性模量等力学性能影响,分析了其对水泥水化产物微观形貌影响,对比了其与采用乳化沥青制备水泥乳化沥青砂浆微观形貌。结果表明,随着REAP掺量增加,REAPMCM抗压、抗折强度与弹性模量均有所降低,折压比有所提高,REAP掺量30%的REAPMCM折压比为28.5%,其相比未掺加REAP砂浆的折压比提高了46.6%;掺入REAP改善了水泥基材料的韧性,但其改善效果随着水泥水化龄期增长而有所降低;随着REAP掺量增加,一方面浆体总孔隙率含量有所增大,另一方面水泥水化产物间填充覆盖的沥青膜面积增大,且其断面显微形貌与相同沥青固含量掺量的乳化沥青砂浆断面基本类似,证实了REAP亦可较好分散、成膜分布于水泥水化产物间,达到了其与乳化沥青乳浊液对水泥基材料改性相类似的使用效果。     

性能优越的沥青橡胶路面

沥青橡胶（AsphaltRubber）的使用不仅可利用废旧轮胎有利于保护环境，而且还有利于路面条件的改善及其寿命的延长。有实验证明：车辆在沥青橡胶路面上比在水泥路面上行驶的噪音至少低５０％；还可以节约能源和提高驾驶舒适性。泰国一项研究表明：沥青橡胶路面的维修周期为５年，比一般路面提高２年。性能优越的沥青橡胶路面@西炎     

国外氯丁橡胶加工应用研究进展

总结了国外氯丁橡胶（ＣＲ）加工性能改进研究，应用研究和ＣＲ／纤维复合材料的新发展。以氯丁二烯齐聚物为软化剂能明显改进ＣＲ的耐热性。芳香族二元胺类及锡剂能增强ＣＲ的阻燃性；ＣＲ在胶带，胶辊，胶布，胶板领域的应用，得到了进一步开发；ＣＲ可与其它并用，用于制造高速行驶货车用轮胎；ＣＲ／短纤维复合物是优良的减震材料，摩擦材料及导电，导热材料，也是一种优良的橡胶改性剂。     

水泥-乳化沥青-环氧乳液复合胶浆硬化机理研究

针对水泥路面表面损伤修补材料应当具有良好的适应性、界面粘结强度高和较强耐久性等特点,对砂浆类修补材料进行复合改性,研发出一种新型有机-无机类复合修补材料--CAE复合胶浆.对不同龄期的CAE砂浆进行抗折、抗压试验以及冲击韧性试验并采用XRD、红外光谱和SEM等微观测试方法研究其硬化机理.研究结果表明,环氧乳液掺量为30％时,CAE复合胶浆抗折强度与普通砂浆差别不大,抗压强度较普通砂浆低,但冲击韧性显著提高.加入乳化沥青和环氧乳液能够延缓水泥水化但不能阻碍水化进程,环氧乳液能够在CAE复合胶浆中完全固化,乳化沥青和环氧乳液固化形成的网络结构与水泥水化产物相互交织穿插,有效改善了CAE复合胶浆材料的孔隙结构.     

Properties of rubberized concretes containing silica fume

A test program was carried out to develop information about the mechanical properties of rubberized concretes with and without silica fume. Two types of tire rubber, crumb rubber and tire chips, were used as fine and coarse aggregate, respectively, in the production of rubberized concrete mixtures which were obtained by partially replacing the aggregate with rubber. Six designated rubber contents varying from 2.5% to 50% by total aggregate volume were used. The concretes with silica fume were produced by partial substitution of cement with silica fume at varying amounts of 5–20%. Totally, 70 concrete mixtures were cast and tested for compressive and splitting tensile strengths, and static modulus of elasticity in accordance to ASTM standards. The design strength level ranging from 54 to 86 MPa was achieved using water–cementitious material (w/cm) ratios of 0.60 and 0.40. Test results indicated that there was a large reduction in the strength and modulus values with the increase in rubber content. However, the addition of silica fume into the matrix improved the mechanical properties of the rubberized concretes and diminished the rate of strength loss. Results also revealed that a rubber content of as high as 25% by total aggregate volume might be practically used to produce rubberized concretes with compressive strength of 16–32 MPa.     

钢纤维高强水泥基复合材料的界面效应及其疲劳特性的研究

通过综合分析提出，钢纤维与水泥基体、集料与水泥浆的界面层不仅可以改善和强化，而且经有效地调整界面区的组成和结构，界面层及其薄弱特征完全能够消失，并且还有丙强化的可能，再强化程度则与界面区组成结构密切相关，这是扩大纤维效应范围、强化空间随机叠加、配制高性能水泥基复合材料的理论基础，本工作还研究了界面效应与高强混凝土，钢纤维高强水泥基复合材料在反复荷载作用下疲劳特性的关系，实验结果表明，因钢纤维与硅灰     

Experimental study on properties of polymer-modified cement mortars with silica fume

This paper discussed the flexural and the compressive strengths of polyacrylic ester (PAE) emulsion and silica fume (SF)-modified mortar. The chloride ion permeability in cement mortar and the interfacial microhardness between aggregates and matrix were measured. The chemical reactions between polymer and cement-hydrated product were investigated by the infrared spectral technology. The results show that the decrease of porosity and increase of density of cement mortars can be achieved by the pozzolanic effect of SF, the water-reducing and -filling effect of polymer. Lower porosity and higher density can give cement mortars such properties as higher flexural and compressive strength, higher microhardness value in interfacial zone and lower effective diffusion coefficient of chloride ion in matrix.     

石墨烯/聚乙烯复合改性沥青胶结料的流变性能研究

为提高沥青胶结料的综合路用性能,尤其是高温性能,本文采用高速剪切机将质优价廉的聚乙烯(PE)与石墨烯纳米片(GNPs)复合制备新型沥青胶结料,同时使用温度扫描(TeS)、多重应力蠕变恢复(MSCR)、线性振幅扫描(LAS)和傅里叶变换红外光谱(FTIR)研究了石墨烯/聚乙烯复合改性沥青胶结料的流变性能和作用机理。结果表明:GNPs和PE能够协同改善沥青胶结料的高温性能,提高路面的高温车辙抗性;预混的PE/GNPs母粒具有良好的中温疲劳和低温开裂抗性。同时复合改性沥青的FTIR光谱中未出现新的吸收峰,表明石墨烯和聚乙烯在沥青基体中以物理改性为主。     

微藻油/苯乙烯-丁二烯-苯乙烯嵌段共聚物复合再生沥青流变特性及疲劳特性

将微藻油（MO）和苯乙烯-丁二烯-苯乙烯嵌段共聚物（SBS）作为复合再生剂掺入老化沥青中,以制备MO/SBS复合再生沥青。对比了复合再生沥青的基本物理性能、高低温流变特性及疲劳特性,考察了MO与SBS的配比和用量对老化沥青再生效果的影响。结果表明,纯MO再生沥青的黏弹性变形能力可在一定程度上恢复至老化前水平,但仍有一定差距;MO/SBS复合再生则可在此基础上显著提升高温抗变形性能及弹性恢复性能,且其临界温度较老化前提高1.1~9.7 ℃,同时还降低了再生沥青对疲劳应变的敏感性以提高其抗疲劳性能。但MO/SBS复合再生沥青的低温蠕变变形能力相较于基质沥青有所降低。当MO和SBS的质量分数分别为8%和4%,复合再生沥青的高低温流变及疲劳特性较佳。     

Freezing and thawing resistance of air-entrained concrete incorporating recycled coarse aggregate: The role of air content in demolished concrete

This study aims to introduce new information on freezing and thawing resistance when air-entrained or non-air-entrained concrete is used as recycled coarse aggregate into air-entrained concrete. The laboratory produced air-entrained and non-air-entrained concretes with a water/cement (w/c) ratio of 0.45 were recycled at the crushing age of 1 year to obtain the coarse aggregates used in the investigations. The recycling process was performed in three stages to produce recycled coarse aggregates with different adhered mortar contents. The results showed that recycled coarse aggregate produced from non-air-entrained concrete caused poor freezing and thawing resistance in concrete even when the new system had a proper air entrainment. Microstructural studies indicated that non-air-entrained adhered mortar caused disintegration of the recycled coarse aggregate in itself and disrupted the surrounding new mortar after a limited number of freezing and thawing cycles. Minimizing non-air-entrained adhered mortar or enhancing the performance of new surrounding matrix could not give satisfactory results for a long freezing and thawing exposure.     

具有核壳结构的聚丁二烯接枝聚苯乙烯改性沥青的性能

采用种子乳液聚合法制备了具有核壳结构的聚丁二烯接枝聚苯乙烯(PB-g-PS),并将其与沥青通过高速剪切共混制备了PB-g-PS改性沥青,考察了PB-g-PS改性沥青的物理性能以及热老化性能、感温性、热贮存稳定性和相容性。结果表明,当PB-g-PS的质量分数为5%时,改性沥青的高温热稳定性、抗低温开裂性较好;与基质沥青相比,改性沥青的热老化性能得到改善,感温性下降;在相同条件下,PB-g-PS改性沥青的热贮存稳定性要好于苯乙烯-丁二烯-苯乙烯嵌段共聚物改性沥青;核壳结构的PB-g-PS与基质沥青具有一定的相容性。     

Fatigue behavior of continuous glass fiber composites: Effect of the matrix nature

The effect of the matrix morphology on the fatigue behavior of a continuous glass fiber/polypropylene (GF/PP) composite system was studied by means of stress‐life and mode II cyclic delamination tests. The stress‐life behavior of a GF composite is considerably affected by the nature of the matrix. A two‐stage fatigue damage curve was observed in the composite made with a PP matrix, whereas a three‐stage curve was observed in the composite made with a thermoset polyester matrix. For a fatigue stress higher than 50% of the yield stress, the PP matrix composite showed a considerably longer fatigue life than the thermoset polyester matrix composite. Mode II cyclic delamination tests showed that the morphology itself of the PP matrix also played an important role. Higher fatigue delamination growth rates, at given strain energy release rates, and lower strain energy release rates at failure were obtained for a composite showing a coarse spherulitic morphology and well‐marked interspherulitic regions than for a composite showing a finer spherulitic morphology and less‐marked interspherulitic regions. While the fatigue mode of the composite with a coarse spherulitic morphology was interspherulitic, that of the composite with a finer spherulitic morphology was transpherulitic.