摘 要：通过试验，分析了超细粉煤灰对不同级配再生混凝土内部裂纹及孔隙的修复填充效应。结果表明，超细粉煤灰能够在一定程度上改善再生混凝土的和易性及强度，但其对不同级配的再生混凝土强度的影响是不尽相同的，在掺入超细粉煤灰后，再生混凝土平均强度可提高15%左右。 Abstract: Through the tests, the filling and repairing effects of ultra-fine fly ash on internal cracks and pores of recycled concrete under different gradations are researched. The results indicate that ultra-fine fly ash could improve the workability and strength of recycled concrete in a certain degree, however, the effects of ultra-fine fly ash on the recycled concrete with different gradations are different. Recycled concrete strength can increase by an average of about 15% after adding ultra-fine fly ash.

摘 要：废弃混凝土类建筑垃圾经过破碎、筛分、二次破碎和研磨等预处理后，可作为再生胶凝材料替代水泥。采用盐和碱对其活性进行激发，研究了废弃混凝土类建筑垃圾的胶凝特性。采用抗压强度、抗折强度、XRD、TG-DSC-DTC和SEM对试样的力学性能和微观结构进行了测试。试验结果表明，废弃混凝土类建筑垃圾具有潜在活性，激发剂可以明显提高其活性。单一激发效果不明显，盐激发和碱激发复合激发效果较好，可以促使其进行水化，提高体系的强度。从微观测试可以看出，掺入复合激发剂的试样中钙矾石等水化产物较多，结构致密，说明水化比较充分。 Abstract: Concrete construction waste can be used as regenerated cementitious material instead of cement through crushing, screening, secondary crushing and grinding pretreatment. Using salt and alkali to stimulate the activity of regenerated cementitious material, the gelling characteristics of concrete construction waste are researched. Compressive strength, flexural strength, X-ray diffraction, thermogravimetry-differential scanning calorimetry, scanning electron microscopy are used to investigate the mechanical properties and microstructure of specimens. The experimental results show that concrete construction waste has potential activity and the activator can greatly improve its activity. Composite activator of salt and alkali has good effect compared to single activator. Composite activator can promote hydration and improve the system strength. Samples doped with composite activator have more ettringite and compact structure through micro-test, which indicate that the samples have full hydration.

摘 要：随着天然砂石自然资源的日渐枯竭，工业废弃物、建筑垃圾和污泥等加工后作为人造粗、细集料用于混凝土，掺入水泥中作混合材，以及作为混凝土的掺合料和矿物外加剂，促进了资源再生利用和节能减排工作。加强废弃物的成分研究，规定其有害物质限量，防止利用不当，造成对环境的二次污染，影响混凝土的耐久性与使用寿命，应是当前研究的重点。 Abstract: Because of the exhaustion of the natural resources as natural sand, industrial waste, construction waste and sewage sludge after processing can be manual coarse or fine aggregates used in concrete, admixtures adding into cement and used as concrete admixtures or mineral additives, which improve the resource regeneration and energy saving. Nowadays, the research key points are aiming at studying the wastes composition, regulating the limit of harmful substance, preventing the adverse using to cause secondary pollution in environment to affect the durability and working lifetime of concrete.

摘 要：现行高层剪力墙结构墙体和楼板混凝土施工中，首先进行墙体混凝土的浇筑，然后进行楼板混凝土的浇筑。这种通行的做法使墙体混凝土与其顶部楼板混凝土之间存在贯通的施工缝，容易出现施工质量问题，同时施工人员停工等待时间过长、无法充分进行流水施工。在齐齐哈尔大学国际交流中心工程剪力墙及楼板混凝土施工中，采用了一种先支设上部楼板模板、后支设下部墙体模板，进而同时浇筑剪力墙和楼板混凝土的施工技术。通过与传统混凝土浇筑方法在施工质量、人员设备及材料投入情况、工期等方面的比较，证明了采用该技术能够明显地提高工程质量、降低人工费用、缩短施工工期。 Abstract: In general, in the concrete construction in the wall and upper floor of high-rise shearing wall structure, the method that pouring concrete for the upper floor after concreting for the wall is used. This common practice produces the construction seams in the concrete between top of wall and upper floor, which is prone to construction quality problems, while the non-work waiting time of workers is too long, which causes them unable to fully carry out the flow construction. In the construction of concrete shearing wall and floor of Qiqihar International Education Center, a new construction technology is used, which is installing floor formwork first and then installing wall formwork, after that pouring concrete of shearing wall and floor at the same time. Compared with the traditional method in construction quality, workers, equipment, material investment, construction period, etc., the new construction technology is proved to be able to shorten construction period, reduce expenses for labor and improve construction quality obviously.

摘  要：通过对二根柱试件（一根免拆卸模板混凝土柱，一根普通混凝土柱）的试验，研究了免拆卸模板混凝土柱在单调荷载作用下的基本力学性能，包括破坏形态、极限承载力、柱侧混凝土应变、受力钢筋应变等，对免拆卸模板-结构混凝土柱与普通混凝土柱的受力性能进行了对比。实验结果表明：采用现行规范计算免拆卸模板-结构混凝土柱的极限承载力具有较高的安全性能；免拆卸模板-结构混凝土柱具有与普通混凝土柱相近的轴心受压性能。Abstract：Basedontheexperimentontwocolumnspecimens(oneisaconcretecolumnwithaformworkwithoutdisassembly,anotherisanordinaryconcretecolumn),thebasicmechanicalpropertiesoftheconcretecolumnwithaformworkwithoutdisassemblyundermonotonicloadingarestudied,includingfailurepatterns,ultimatebearingcapacity,concretestrain,strainofreinforcingsteelandsoon.Thecomparisonofmechanicalbehaviorismadebetweentheconcretestructurecolumnwithaformworkwithoutdisassemblyandanordinaryconcretecolumn.Theexperimentalresultsindicatethattheultimatebearingcapacityoftheconcretestructurecolumnwithaformworkwithoutdisassemblyhassaferperformancewhileusingthecurrentspecificationtocalculateit,anditsaxialcompressioncapacityisapproximatetotheoneofanordinaryconcretecolumn.

摘 要：采用十二烷基硫酸钠和X-305作为乳化剂，PVA作为保护胶体，过硫酸钾作为引发剂，制备了通用型可分散乳胶粉。研究了可再分散乳胶粉对砂浆容重、力学性能、粘结强度、保水性能和吸水性能的影响规律。研究结果表明：掺量小于15%时，砂浆的容重随胶粉掺量的增加而降低，但当掺量达到20%时容重开始增加；砂浆的抗压强度随着胶粉掺量的增加而减小，抗折强度随着胶粉掺量的增加而增加，压折比随着胶粉掺量的增加而降低；砂浆的粘结强度随着胶粉掺量的增加而增加；砂浆的蒸发量、吸水量随着胶粉掺量的增加而降低。 Abstract: Through using sodium dodecyl sulfate and X-305 as emulsifier, PVA as protective colloid, potassium persulfate as initiator, the general type dispersed emulsion powder is prepared. The effective laws of dispersed emulsion powder on bulk density, mechanical properties, bonding strength, preserving water property and water absorption of mortar are studied. The results show that when the dosage of emulsion powder is less than 15%, the bulk density of mortar decreases with the increasing dosage of emulsion powder, however, when the dosage of emulsion powder reaches 20%, the bulk density begins to increase. When the dosage of emulsion powder increases, the compressive strength of mortar will decrease, the flexural strength will increase, the ratio of compressive strength to flexural strength will decrease, the bonding strength of mortar will increase, the evaporation and the water absorption will decrease.