钢筋滚压直螺纹连接的有限元分析

钢筋滚压直螺纹连接技术在国内外已经广泛使用,但目前没有国家的行业标准,本文通过对滚压直螺纹连接技术的强度和连接最小螺纹扣数进行了试验研究和有限元分析,给出了比较合适的最小螺纹旋和长度和螺纹扣数(9～11扣),为今后该项技术的运用提供参考.     

20MnSiV(N)新Ⅲ级螺纹钢筋的开发

介绍了宣钢开发20MnSiV(N)Ⅲ级钢筋的过程，并对20MnSiV(Ⅲ）级钢筋中V、N的强化原理作了简要分析。     

中型轧钢厂螺纹钢负公差的生产改进实践

通过对中型轧钢厂螺纹钢负公差生产工艺的优化及生产过程的控制，生产出符合国家标准要求的螺纹钢；螺纹钢的负公差率得到提高。     

On‐site investigations on concrete resistivity – a parameter of durability calculation of reinforced concrete structures

For determination the electrolytic resistivity of concrete, resistances of realistic designed probes are measured during a one and two year period, respectively. Measurements are made with a commercially available instrument normally used for measuring earth resistances. Comparison to other usually applied methods show not only that the used method GEOHM is qualified for measuring the electrolytic resistance of concrete but also that the magnitude of measured values is realistic. To obtain electrolytic resistivities from these measurements the individual cell constant for the investigated system was derived from experimental research. First results of the in‐situ stored specimens are presented, intended future activities are sketched.     

新技术新材料在某住院楼工程中的推广应用

针对孝义市人民医院的工程特点,阐述了该工程的质量目标和施工目标,对施工中采用的混凝土裂缝防治措施、高效钢筋应用技术、新型模板应用技术、钢结构应用及安装技术等进行了分析,指出通过新技术新材料的应用,工程质量达到了优良标准.     

适用于海水海砂混凝土阻锈剂的作用机理

采用X射线衍射、扫描电镜和X射线能谱、傅里叶变换拉曼光谱等方法分别研究了复合型阻锈剂对海水海砂混凝土中水泥水化作用、钢筋与混凝土交界面微观结构与组成、钢筋表面吸附的影响。结果表明,阻锈剂C3对水泥水化有一定的延缓作用,可以提高混凝土密实程度,对混凝土强度无不利影响,并且可以通过氨甲基丙醇的物理吸附作用、乙烯基三乙氧基硅烷的密封作用、单氟磷酸钠的化学反应沉淀作用等稳定地富集于钢筋与混凝土交界面处,增强钢筋及其钝化膜的稳定性。     

水工压力隧洞设计与计算方法研究

采用弹性力学理论与经济性处理相结合的研究方法．对弹性力学计算公式进行了重新推导；同时采用Ansys有限元，对结构的强度和限裂要求进行分析与验算并与理论公式加以比较分析。结果表明：重新推导的计算公式更简洁、更直观、更符合实际。     

Corrosion Process and Mechanisms of Corrosion‐Induced Cracks in Reinforced Concrete identified by AE Analysis

Abstract: Concrete structures could suffer from the corrosion of reinforcing steel bars (rebars) because of the penetration of chloride ions. For crack detection and damage evaluation in concrete, acoustic emission (AE) techniques have been extensively applied to concrete and concrete structures. In the corrosion process of reinforced concrete, it is demonstrated that continuous AE monitoring is available to identify the onset of corrosion and the nucleation of concrete cracking because of the expansion of corrosion products. At the latter stage, the expansion of corrosion products generates corrosion‐induced cracks in concrete. The generating mechanisms of these cracks are studied in accelerated corrosion tests of reinforced concrete beams. Kinematics of microcracks are identified by SiGMA (Simplified Green’s functions for Moment tensor Analysis) analysis of AE. It is demonstrated that AE activity at the onset of corrosion and at the nucleation of corrosion‐induced cracks is in remarkable agreement with the phenomenological model of the corrosion process in steel. Then, mechanisms of corrosion‐induced cracks are visually and quantitatively investigated by the SiGMA analysis.     

植筋群受拉有限元分析

利用大型有限元软件ANSYS10.0对化学植筋试件进行了非线性有限元分析.分析中假定粘结应力均匀分布,分析了埋深为10 d和15 d情况下植筋的极限拉力、荷载作用下钢筋应力沿长度的变化及钢筋荷载-应变曲线并同试验结果进行了对比,计算了在不同边距和不同间距下的承载力并同已有计算公式计算结果进行对比.结果表明,在分析中可以采用粘结应力均布的模型.在考虑边距和间距对承载力影响时,可以采用喜利得公司的公式计算植筋群的受拉承载力.