摘  要：在对不同钼尾矿粉的需水量比及活性测试的基础上，研究了钼尾矿粉对混凝土工作性能、力学性能及耐久性的影响。结果表明，当钼尾矿粉比表面积为547m2/kg时性能最好。在混凝土中替代水泥量不大于10%的条件下，可以改善混凝土工作性，提高混凝土的强度，同时不影响混凝土的抗碳化、抗冻融性能。但随着磨细钼尾矿替代量的继续增加，混凝土的各项性能明显变差。Abstract:Basedonthetestofwaterdemandandactivityofdifferentmolybdenumtailingspowder,theeffectofmolybdenumtailingspowderontheconcreteproperty,mechanicalpropertiesanddurabilitywerestudied.Theresultshowedthat,theperformanceofmolybdenumtailingwasbestwhenitssurfaceareais547m2/kg.Whenthecementsubstitutionquantitybymolybdenumtailingpowerislessthan10%,theconcretecompressivestrengthandworkabilitycanbeimproved.Meanwhile,ithasnoeffectonanti-carbonizationnorcapabilityfrost-resistance.Thepropertiesofconcretedecreaseastheadditionalquantitykeepincreasing.

摘 要：利用钛石膏单掺、钛石膏与天然石膏复掺制备P·Ⅰ型水泥研究钛石膏作水泥缓凝剂的可行性。对制备的P·Ⅰ型水泥进行了物理力学性能和水化放热特性研究，通过XRD、SEM对水泥水化产物的物相和微观形貌进行了分析。研究结果表明，单掺钛石膏会增大水泥标准稠度用水量，缩短凝结时间，但其强度与单掺天然石膏试样强度相当；对于钛石膏和天然石膏复掺的水泥，随着钛石膏掺量增加，其标准稠度用水量增加，凝结时间先增大后减小，在钛石膏掺量为2.50%时凝结时间最长，强度均先增加后减小，在钛石膏掺量为1.25%~3.75%时，试样28d抗压强度均高于对照组。掺加钛石膏的水泥安定性合格，标准稠度用水量、凝结时间和强度均符合标准要求。 Abstract: P·Ⅰ cement was prepared by using titanium gypsum and a mixture of titanium gypsum and natural gypsum to study the possibility of making use of titanium gypsum as setting retarders. The basic physical properties and hydration heat characteristics of P·Ⅰ cement were studied. The phases and microstructures of cement hydration products were investigated by XRD and SEM. The results showed that adding titanium gypsum would increase normal consistency, shorten the setting time, and its strength is same as which using natural gypsum. With the increase of dosage of titanium gypsum, the normal consistency of double mixed titanium gypsum and natural gypsum cement increase, and the setting time first increases then decreases. When the titanium gypsum dosage is 2.50%, the setting time reached longest, as the dosage increased from 1.25% to 3.75%, its 28d compressive strength is higher than the control group. The soundness of P·Ⅰ cement with titanium gypsum could meet the demand, the setting time, normal consistency and strength are conform to the standard.

摘 要：用镍渣代替地面用水泥基自流平砂浆中的骨料和填料，研究其对自流平砂浆流动度、耐磨性及抗折抗压强度等性能的影响。结果表明，镍渣作为骨料取代天然石英砂应用在地面用自流平砂浆中是完全可行的，镍渣作为填料具有增加自流平砂浆后期强度的功能，用镍渣作骨料和填料制备的地面用水泥基自流砂浆具有耐磨性能好、后期强度高、表面不易粉化、价格低等特点，且各项技术指标等均符合JC/T 985—2005标准规定的要求。 Abstract：Nickel slag take the place of the aggregate and filler of the ground cement based self leveling mortar. The influence on the self leveling mortar fluidity, resistance, flexural and compressive strength were studied. The results show that Nickel slag as aggregate replace the natural quartz sand on the ground is feasible, Nickel slag as filler can increase the self leveling mortar late strength, Nickel slag as aggregate and filling to prepare ground with cement based self mortar has good abrasion resistance, high late strength, high surface toughness, low price etc, and each technical indicator can meet the requirements of the JC/T 985—2005 standard.

摘 要：结合PCC桩在长江下游某在建船闸工程中的应用情况，在现场对PCC桩施工工艺进行了检测和试验研究，探讨了混凝土坍落度、拔管速度和充盈系数等重要的施工控制参数对PCC桩质量的影响，总结了PCC 桩施工的关键控制技术，为类似工程提供一定的参考和借鉴。 Abstract: Combined with the application of PCC piles in a lock engineering in lower reaches of Yangtze River, the collapse degree of concrete, velocity of pile extraction and fullness coefficient of concrete of PCC piles during construction are studied in detail by experimental research. Based on the test results, the correlative advice about construction controlling and key technique of the PCC pile is put forward.

摘 要：本次标准修订中对GB/T 15345—2003《混凝土输水管试验方法》标准的范围、规范性引用文件、术语和定义、外观质量、几何尺寸、水压、外压荷载、混凝土强度、保护层砂浆抗压强度、保护层砂浆吸水率以及管子接头相对转角等项目都作了不同程度的修改。为了方便使用新版标准的各类人员加深对各个项目试验方法的理解，本文基于标准修订编制说明的内容对新标准的主要变化之处进行了比较完整的说明。 Abstract: Some chapters and sections of the national standard GB/T 15345—2003 "Test methods of concrete pipes for water transmisson" have been revised in different degrees such as scope, normative references, terms and definitions, appearance quality, geometry size, hydraulic pressure, external pressure load, concrete strength, compressive strength of protective cover mortar, water absorption of protective cover mortar, pipe joint relative rotation and so on. In order to facilitate users to accurately implement the specific requirements of the new standard terms and rules, the background, purpose and significance of the new standard are introduced, and the major changes of the new standard are explained.

摘 要：通过大量的配合比试验分析了全轻页岩陶粒混凝土抗压强度的主要影响因素，进而确定了全轻页岩陶粒混凝土的最优配合比。试验结果表明，页岩陶粒混凝土抗压强度主要取决于陶粒本身的筒压强度、密度等级和粒径、水灰比、砂率和陶粒是否预湿；与普通混凝土一样，每一个强度等级都存在一个最优砂率；不同筒压强度的陶粒只能配制出相应强度等级的页岩陶粒混凝土；与普通混凝土相比， 全轻混凝土7d和28d的抗压强度增长幅度较小；骨料经过预湿的7d和28d的全轻混凝土抗压强度均低于骨料未预湿的，但骨料经过预湿的混凝土拌合物和易性较好。 Abstract: The main factors of the compressive strength of full lightweight shale ceramsite and sand concrete were analyzed by many mix ratio test to determine the optimum mix proportion. The results showed that the strength of the full lightweight shale ceramsite and sand concrete depends on the strength, density and size of aggregate, water-cement ratio, sand ratio and whether the aggregate is preweting. There is an optimal intensity level sand ratio in each of the strength grade of the full lightweight shale ceramsite and sand concrete. The different strength of aggregate can only prepare corresponding compressive strength of the full lightweight shale ceramsite and sand concrete. Compared with ordinary concrete, the increment of 7d and 28d strength of the full lightweight concrete is smaller. The compressive strength of the aggregates which are not pre-wetted is larger than the pre-wet aggregates, but the pre-wet concrete workability is better.