浅谈沥青混凝土路面离析及防治措施

沥青混凝土路面具有:表面平整、路面坚实、不设接缝、行车舒适、耐磨性好、振动较小、噪声较低;晴天无尘土,雨天不泥泞;在烈日照射下不反光,便于行车;施工期短、养护维修简便、开放交通快等优点,而得到了广泛运用。然而由于施工人员的疏忽,因路面离析原因发生的质量事故屡见不鲜。本文将通过自身实践得出一些经验来分析离析发生的原因及防治措施。     

浅析混凝土离析问题产生的原因与解决措施

混凝土是现代建筑工程中一种常用的建筑材料,随着混凝土在现代建筑工程中的应极大的提高了现代建筑工程的质量和性能,从而使得现代建筑工程的水平得到了实质性提升.然而在现代的建筑工程中,却通常会产生混凝土离析问题,当混凝土产生离析时,不仅给混凝土的质量造成严重影响,而且还会造成巨大的工程成本浪费.而为了确保建筑工程的质量和性能,必须要针对混凝土离析问题采取有效的解决措施.因此在现代的建筑工程中加大对混凝土离析问题的研究力度不仅意义重大,而且迫在眉睫.本文通过对混凝土离析的深入研究,并对其产生原因进行了综合性分析,然后提出了对应的解决措施,以供同行参考.     

试析沥青路面施工离析现象的成因及控制办法

如今,随着社会和经济的发展,交通公路也渐渐的凸显出它的重要性。目前我国的公路大部分是沥青路面,因为沥青路面的成本比较低、使用性能也很好。但是在使用一段时间之后,路面免不了会出现一些问题,比如离析现象。笔者对沥青路面出现离析现象的原因及控制措施作了一系列的探讨,希望对广大的相关工作者能够有所帮助。     

浅析高速公路基层施工中的离析现象

结合在高速公路基层施工施工过程中,骨料离析是水泥碎石基层施工中比较常见的问题之一,在施工过程中经常会出现局部离析现象,在细集料相对含量较少粗集料较多的部位空隙较大,板体性差、容易渗水,极易发生早期破坏,特别是在骨架密实型中较为突出。离析产生的原因涉及到基层施工中各个环节。本文从施工角度,对基层施工中离析现象原因及控制措施进行阐述:以人、机、车,原料的生产、混合料的拌合、运输、摊铺、碾压等环节为出发点,通过合理的调整、配置、有条件改造等手段减少公路基层施工中的离析现象,从而保障基层施工质量,顺应现代公路施工发展方向。     

干混砂浆成品仓防离析装置

为进一步解决混砂浆在进入成品仓时发生离析的问题,设计了一套防离析溜管装置,该装置的应用,实现了干混砂浆在成品仓内的整体下落,下落干净、顺畅,有效防止了离析现象的出现,节省了生产成本,保证了成品的质量.     

干混砂浆成品仓防离析装置

为进一步解决混砂浆在进入成品仓时发生离析的问题,设计了一套防离析溜管装置,该装置的应用,实现了干混砂浆在成品仓内的整体下落,下落干净、顺畅,有效防止了离析现象的出现,节省了生产成本,保证了成品的质量。     

离析对沥青稳定碎石路用性能的影响

为了研究离析对沥青稳定碎石路用性能的影响,采用制作的大马歇尔试件进行了浸水马歇尔试验、混合料车辙试验和构造深度试验,研究了离析对混合料三个方面的影响。研究结果表明:混合料离析造成粗集料集中区域水稳定性变差;混合料离析导致粗集料集中区域性能变差;离析对沥青混合料各方面性能影响有着较大差异。     

沥青混合料离析的危害及防治措施

沥青混合料在生产过程中。由于石料堆放、运输、拌和、储存、装卸、摊铺和碾压的温度和施工条件的影响,会造成沥青混合料未按设计级配进行填充,导致沥青混合料施工的不均匀的现象,称之为离析。离析按其成因分为集料离析,温度离析和人为离析。一、沥青混合料离析的危害1.导致沥青路面水损坏;粗集料过多的离析部位,往往缺少大部分细集料,沥青含量低,空隙率大,渗水进人后,在长期行车荷载和高速轮压产生的强大冲击力作用下,对滞水层面产生水损坏。2.导致沥青路面受力发生变化:离析部位集料粗细分离,或油石分离,沥青料局部组成结构发生变化,混合料内部强度和粘结力降低因而严重影响路面的强度均匀性和抗剪度。在行车荷载作用下极易发生形变和松散,从而破坏路面。增加路面的后期养护费用和使用难度。     

沥青路面施工及维护中常见的问题及解决措施

沥青道路的质量与施工和后期的维护有着密切的联系，施工的质量好坏决定了带路的寿命，而养护维修则决定了道路的寿命长短，两者相互依存，相互制约。本文就沥青路面施工中的离析现象问题以及后期的道路养维修新技术新方法进行了详细的论述，以供广大同行参阅。     

中国饲料工业协会第五届理事会顾问、会长、常务副会长、副会长、秘书长、副秘书长、常务理事、理事名单

顾问刘中一张德邻宋瑞祥聂振邦张子仪戎易王维四会长白美清国务院原副秘书长、第四届理事会会长常务副会长(8人,以姓氏笔划为序)刘永好新希望集团董事长、第四届理事会副会长刘汉元通威股份有限公司董事长、第四届理事会副会长陈丹广东恒兴集团股份有限公司董事长、第四届理事会副会长张延喜农业部原副部长、第四届理事会副会长吴明夏湖南正虹科技发展股份有限公司董事长、第四届理事会副会长陶一山唐人神集团股份有限公司董事长、第四届理事会副会长温鹏程广东温氏食品集团有限公司董事长、第四届理事会副会长谭竹洲原化学工业部副部长、第…     

Evidence for the non-involvement of the uterus in the lifespan of the corpus luteum in the cyclic dog

Progesterone levels in peripheral blood of dogs were analysed during the cycle in which hysterectomy (n = 5) or sham surgery (n = 3) was performed as well as during the cycle of dogs (n = 5) hysterectomized at least one year prior to this study; the data were compared with the findings in control dogs (n = 3). The averages of the duration of the luteal period observed in the three experimental groups were not significantly different from those of control dogs. Immediately after surgery, the progesterone level decreased from 25 to 50% of the presurgical level, but returned to presurgical level in about four days. Prolactin levels were elevated for about 30 h after surgery. Nevertheless, the averages of the mean prolactin levels for each animal during the luteal period of the experimental groups were not significantly different from those of control dogs. It is concluded that in the dog, the uterus is not involved in the lifespan of the cyclic corpus luteum.     

The influence of the width of the saddle tree on the forces and the pressure distribution under the saddle

As there is no statistical evidence that saddle fit influences the load exerted on a horse's back, this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as "too-narrow" if they were one size (2 cm) narrower than the LOF saddle, and "too-wide" if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as "very-wide". In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm(2)+/-0.10; trot 1.08 N/cm(2)+/-0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm(2)+/-0.09; trot 0.86 N/cm(2)+/-0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm(2)+/-0.06; trot 1.52 N/cm(2)+/-0.19) and very-wide saddles (walk 0.77 N/cm(2)+/-0.06; trot 1.57 N/cm(2)+/-0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm(2)+/-0.10/ 0.63 N/cm(2)+/-0.11; trot 1.33 N/cm(2)+/-0.22/1.27 N/cm(2)+/-0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks.     

浅谈对症用药

对症用药就是通过对患病信鸽的症状进行诊断,进而确定病属,选择药物及如何用药的方法。     

军犬鉴别中的嗅源培养和易出现的问题及对策

嗅源是军犬嗅觉作业训练的依据.军犬鉴别中嗅源能力的培养在整个鉴别训练中占有重要地位,关系到鉴别训练的成败和鉴别能力的提高.所以,军犬在嗅认嗅源时必须按照训犬员的指令充分、细致地感受嗅源气味,并且对嗅源气味产生兴奋反应.如何培养军犬充分嗅认嗅源以及及时解决嗅认过程中出现的问题,成为我们进行鉴别训练的关键.……