火灾高温下盾构管片接头橡胶防水性能劣化规律试验研究

为了研究盾构管片在火灾高温下引起的接头密封橡胶条防水性能的劣化规律,对复合接头橡胶条材料进行了耐高温试验。试验结果表明:(1)温度及压缩量对于管片接头防水性能影响较大,在橡胶条位置达到170℃以后,接头张开量达到6mm以上,防水性能全部失效;(2)遇水膨胀橡胶的耐火性能较差,在密封橡胶条整体还未达到耐高温极限时,遇水膨胀橡胶部分防水性能已经失效;(3)在170℃以下,接头密封橡胶条弹性并未完全失去,可以通过增加压缩量产生较大压缩应力来达到止水目的。     

聚氨酯遇水膨胀弹性体防水性能研究

聚氨酯遇水膨胀弹性体材料是目前地下工程防水应用的新型材料,本文阐述了其性能特点,介绍了其在国内外的应用发展情况。与目前国内常用的共混型遇水膨胀橡胶相比,聚氨酯遇水膨胀弹性体在膨胀性能、应力松弛、使用寿命等方面都存在显著优势。     

遇水膨胀橡胶的研制及应用进展

阐明了遇水膨胀橡胶的止水密封机理 ,综述了遇水膨胀橡胶的种类和制备方法 ,并探讨了遇水膨胀橡胶在应用中遇到的问题以及止水密封性的判定方法。     

盾构隧道遇水膨胀橡胶密封垫止水性能试验研究

运用密封垫静态密封原理及交联橡胶的统计理论 ,对盾构隧道衬砌环缝遇水膨胀橡胶密封垫的膨胀性能及不同工况下耐水压性能进行试验 ,从而分析遇水膨胀橡胶密封垫的止水机理 ,并评述其在隧道中的止水能力 ;同时 ,为盾构隧道衬砌接缝遇水膨胀橡胶密封垫防水的设计、施工提出几点建议。     

地铁盾构隧道管片接缝复合型密封垫防水研究

针对盾构管片接缝密封垫单一型与复合型密封垫断面,利用非线性有限元软件ABAQUS对盾构隧道密封垫防水进行数值模拟研究,分别对单一型密封垫和复合型密封垫在不同张开量条件下的防水性能进行量化分析,并通过复合型密封垫遇水膨胀橡胶块的膨胀作用进行分析。研究表明:(1)随着接缝张开量不断增大,复合密封垫的防水性能逐渐由密封垫压缩产生的接触应力转化为遇水膨胀橡胶的膨胀作用产生的膨胀应力,对比单一型密封垫,其具有二次防水效果;(2)增大复合密封垫遇水膨胀橡胶块厚度与宽度有利于提高密封垫二次防水性能,其防水性能在允许张开量范围内和允许张开量范围外分别增长39%和117%左右,同时考虑应力松弛因素,需要对遇水膨胀橡胶块几何截面进行合理取值。     

某地铁车站变形缝渗漏治理

某地铁车站站厅及设备房出现多处渗漏,其主要原因是变形缝处的防水卷材失效。介绍了采用多层复合防水卷材、遇水膨胀嵌缝胶、遇水膨胀橡胶片等材料对变形缝治理的方案。     

盾构隧道遇水膨胀橡胶密封垫止水性能试验研究

运用密封垫静态密封原理及交联橡胶的统计理论，对盾构隧道衬砌环缝遇水膨胀橡胶密封垫的膨胀性能及不同工况下耐水压性能进行试验，从而分析遇水膨胀橡胶密封垫的止水机理，并评述其在隧道中的止水能力，同时，为盾构隧道衬砌接缝遇水膨胀橡胶密封垫防水的设计，施工提出几点建议。     

上海世博园区预制预应力综合管廊接头防水性能试验研究

通过足尺模型试验,对2010年上海世博会园区预制预应力综合管廊接头的防水性能进行了较为系统的研究。结果表明,预制预应力综合管廊具有良好的接头防水性能,能够满足设计要求。基于试验结果,建立了遇水膨胀橡胶条压力计算公式,并拟合得到了遇水膨胀橡胶条的压力-变形关系式。在上述研究工作的基础上,提出了2010年上海世博会园区预制预应力综合管廊接头防水构造的优化建议,该建议已被工程设计采纳。     

BW止水条在地下工程堵漏中的应用

ＢＷ止水条在地下工程堵漏中的应用解放军工程兵指挥学院于江，何天明，傅香如ＢＷ止水条属于腻子型遇水膨胀橡胶类材料，具有遇水膨胀而止水的性能及施工方法简便等特点，在国防工程中的坑道、人防工程中的地下干道、建筑工程中的地下室、交通工程中的地铁和水利工程中的...     

遇水膨胀橡胶在施工缝防水中的应用

我国一些重要地下工程的混凝土施工缝已大量采用遇水膨胀橡胶条作防水处理,如宝钢一、二期地下工程、上海地铁工程等,应用效果良好。遇水膨胀橡胶是由经过特殊处理的水膨胀橡胶构成,如：丁基橡胶、氯丁橡胶、聚氨酯橡胶,此类物质遇水润湿时,亲水剂同水结合发生膨胀,...     

Water Cut-Off Performance of H-Jointed Steel Pipe Sheet Piles with H-H Joints Attaching Water-Swelling Materials

In this research, under various conditions, we evaluate the water cut-off performance of H-jointed steel pipe sheet piles (SPSPs) with the H-H joints attaching water-swelling materials which are components of SPSPs for water cut-off in a coastal waste landfill site. Specifically, we research the water cut-off performance when these H-H joints have foreign particles, when they are in a wet-dry cyclic condition, and when the water-swelling material has deteriorated. As a result of this research, it has been found that in any of the above cases, H-jointed SPSPs with H-H joints attaching water-swelling materials are capable of providing water cut-off performance, and meet seepage control work standards as long as they are under less than certain pressure levels to be considered in coastal waste landfill sites. Also, it has been proved that the above conditions do not affect the water cut-off performance of H-jointed SPSPs with H-H joints attaching water-swelling materials.     

复合绝缘子用硅橡胶材料的配方设计与老化性能评估

从复合绝缘子的设计、制造、运行等各阶段,就如何开展硅橡胶材料的性能检测和评估,如何采取有效方法去甄别各个制造企业所提供复合绝缘子材料性能的优劣,阐述了当前的技术认识和发展方向。研究认为,为保证复合绝缘子正常的使用寿命,避免复合绝缘子非正常老化,需从设计阶段的配方筛选试验、制造阶段的型式试验和抽样试验、运行阶段的抽检试验、微观检测分析技术等多方面实施质量管控,确保使用设计合理、制造质量合格的复合绝缘子产品。为指导运行维护,最后还提出了硅橡胶材料老化特征参量和分级方法,实现现场评估硅橡胶材料的运行性能。     

Mercury(II) sorption by waste rubber

Studies were connected to assess the capability of waste tire rubber for removing inorganic mercury from solution. Samples of vulcanized tire rubber were ground to a suitable sorbent size and utilized in batch sorption studies. Research parameters included aqueous mercury concentration, rubber sorbent particle size, solution temperature, and hydrogen ion concentration. Alternate sulfur-free rubber materials were also evaluated in an attempt to identify the sorption mechanism. The studies showed tire rubber to be an efficient sorbent material for mercury removal from waste solutions. Of the parameters investigated, pH was determined to be most crucial, with an optimum pH range of 5.5 to 6.0 for good mercury removal. The diffusion of mercury through pores in the rubber sorbent was shown to be the rate limiting step regarding mercury uptake. Finally, sulfur-free rubber materials were shown to be equally efficient for inorganic mercury removal.     

环氧树脂改性橡胶集料砂浆碳化性能的试验研究

系统研究40、80目橡胶粉等质量取代天然砂,复掺环氧树脂制备砂浆的碳化性能。正交试验结果表明:环氧树脂明显减小砂浆的碳化深度,显著提高砂浆的抗碳化能力;40目橡胶粉对砂浆抗碳化能力不利,但影响不显著;80目橡胶粉不利于基体砂浆的抗碳化性能,且对长期碳化性能的不利影响更显著。充分考虑试验分析结果和经济效益,各组分的最佳配合比:环氧树脂掺加13%,40、80目橡胶粉各掺加3%时综合性能最优。     

Micromechanical analyses of the effect of rubber size and content on sand-rubber mixtures at the critical state

This study presents a series of monotonic drained triaxial tests consisting of mixtures of sand (stiff) and rubber (soft) particles simulated by the discrete element method (DEM). Sets of mixtures were prepared with different rubber size ratio of 1, 2.5 and 5 and contents ranging from 0% to 30% by weight. The numerical samples were sheared up to large axial strains to reach a critical state. The slope of the critical state lines is strongly affected when the rubber size is the same as sand. When rubber size increases, the critical state lines shift downward with little effect on the slope. While it is generally accepted that, for the given range of rubber contents used in the study, the sand-rubber mixture strength increases when adding rubber particles, the results from this study suggest that said strength diminishes as rubber size is incremented. Micro-scale information, including coordination number, geometrical and mechanical anisotropy, was obtained for all the tests. Regardless of the rubber particle size, rubber-sand contacts represent an important contribution to the overall strength of the material; however, the rubber particle size dictates how said contribution takes place. These findings highlight the importance of understanding new geomaterials to practicing engineers that different size ratios and rubber contents have positive or negative effect of strength and deformability and the choice of a sand-rubber mixture has to be based on the project nature.     

橡胶粉改性水泥基灌浆材料保温性能的研究

通过掺加不同粒径的橡胶颗粒研究水泥基灌浆材料的物理性能和力学性能。测试改性后水泥基灌浆材料的流动度、抗折抗压强度、24h竖向膨胀率和导热系数。试验结果表明,掺入橡胶颗粒可以部分提高水泥基灌浆材料的流动度和24h膨胀率,影响水泥灌浆材料的部分强度,但基本满足国家三类水泥基灌浆材料的强度要求,同时可以有效降低水泥基灌浆材料的导热系数,改善水泥基灌浆材料的保温性。综合水泥基灌浆材料的物理性能和力学性能,掺入橡胶组份D(即混合三种不同橡胶粒径的组份)的水泥基灌浆材料性能较好。     

废旧橡胶、聚合物改性水泥基复合材料性能初探

针对橡胶改性混凝土抗压和抗折强度较普通混凝土下降的特点,提出橡胶、聚合物改性水泥基复合材料的结构模型,通过对其砂浆试件基本力学性能的测试和比较,分析并验证了该材料结构模型力学性能的优越性.该材料提高了单纯橡胶改性水泥基材料抗压和抗折强度,具有较高弹、韧性和变形能力,有一定的路用价值.     

Using thermodynamic parameters to study self-healing and interface properties of crumb rubber modified asphalt based on molecular dynamics simulation

The thermodynamic property of asphalt binder is changed by the addition of crumb rubber, which in turn influences the self-healing property as well as the cohesion and adhesion within the asphalt-aggregate system. This study investigated the self-healing and interface properties of crumb rubber modified asphalt (CRMA) using thermodynamic parameters based on the molecular simulation approach. The molecular models of CRMA were built with representative structures of the virgin asphalt and the crumb rubber. The aggregate was represented by SiO₂ and Al₂O₃ crystals. The self-healing capability was evaluated with the thermodynamic parameter wetting time, work of cohesion and diffusivity. The interface properties were evaluated by characterizing the adhesion capability, the debonding potential and the moisture susceptibility of the asphalt-aggregate interface. The self-healing capability of CRMA is found to decrease as the rubber content increases. The asphalt-Al₂O₃ interface with higher rubber content has stronger adhesion and moisture stability. But the influence of crumb rubber on the interfacial properties of asphalt-SiO₂ interface has no statistical significance. Comparing with the interfacial properties of the asphalt-SiO₂ interface, the asphalt-Al₂O₃ interface is found to have a stronger adhesion but a worse moisture susceptibility for its enormous thermodynamic potential for water to displace the asphalt binder.