OU组合型板桩在地道基坑中的施工关键技术

结合工程实际,介绍了OU组合型板桩的关键施工技术,包括钢管桩加工、锁扣加工、打桩架设计、沉桩与拔桩工艺等。与传统钢板桩支护相比,OU组合型板桩具有抗弯刚度大、钢管桩长度调整灵活的特点,特别是对于开挖深度7～10m的地道式基坑,更具有性价比突出、施工工期短的优点。     

冬瓜山铜矿掘进工作面强化通风与降温技术

热害是冬瓜山铜矿生产中存在的一个实际问题。在分析冬瓜山铜矿热源情况和借鉴其他矿山实践经验的前提下，提出了以加强通风降温为主的降温措施。针对巷道掘进独头工作面通风和降温要求，进行了掘进工作面强化通风设计和现场实验。现场实验表明，强化通风缩短了排炮烟的时间，大大提高了工作效率；工作而的气温从31．2℃降低到28．8℃，在通风和洒水共同作用下，降低了空气温度、相对湿度和粉尘浓度，使作业环境明显改善。风筒的百米漏风率只有3．67％，这种风筒作为压入式风筒使用时，具有很明冠的优点，值得推广，但是在强化通风的条件下，不能作为抽出式风筒使用。     

龙门式复合材料自动铺丝机研发设计

先进复合材料具有高比强度、抗疲劳、耐腐蚀、设计制造一体化的特点,其在飞机上的用量和应用部位已经成为衡量飞机结构先进性的重要标志之一,而用于制造复合材料整体构件的自动铺丝设备成为现代飞机制造的关键设备。按照铺放16纤维丝束的要求,开发了具有自主知识产权的龙门式自动铺丝设备。     

万家寨水电站水轮机防磨蚀措施及应用现状

介绍了万家寨水电站 1号水轮机、 2号水轮机在设计和制造过程中采用的抗磨蚀措施 ,对机组经过运行后 ,抗磨涂层尤其是耐而久涂层的应用现状及涂层破坏原因作了探讨     

建筑节能政策性保障措施研究

从现阶段我国建筑节能法规、标准及政策入手,分析了现行节能政策的不足之处,通过借鉴国外成功经验,对政府有关部门提出一些建设性的建议。     

庆元县后广流域山洪防御全国试点工作方案技术探讨

庆元县后广流域山洪防御是全国首批试点单位,也是浙江省唯一的试点单位,临界雨量、防洪风险图、山洪预警系统是小流域山洪防御的重要组成部分。     

一种新式键槽中心对称度测量仪的设计

针对目前键槽对称度测量仪存在的不足,设计一种操作方便、读值直观、精度较高的键槽中心对称度测量仪。阐述装置结构和测量方法,并给出一个具体实例。     

基于图像特征和Hopfield的手写体数字识别

基于粗网格特征提取再和Hopfield神经网络相结合的识别方法:首先用粗网格提取特征向量组,再将向量组分为8个分向量,然后再作为Hopfield的输入向量,进行识别,经过对样本的仿真、测试,有着良好的识别效果。     

Effect of Reduction on Bonding Interface of Hot-rolled Wear-resistant Steel BTW1/Q345R Cladding Plate

Wear-resistant cladding plates consisting of a substrate(Q345 R) and a clad layer(BTW1) were bonded through hot rolling at the temperature of 1 200 ℃ and a rolling speed of 0.5 m/s. The microhardness of the cladding plate was also tested after being heat treated. The microstructure evolution on the interface of BTW1/Q345 R sheets under various reduction rates was investigated with a scanning electron microscope(SEM) and EBSD. It is found that the micro-cracks and oxide films on the interface disappear when the reduction is 80%, whereas the maximum uniform diffusion distance reaches 10 μm. As a result, a wide range of metallurgical bonding layers forms, which indicates an improved combination between the BTW1 and the Q345 R. Additionally, it is discovered that the unbroken oxide films on the interface are composed of Mn, Si or Cr at the reductions of 50% and 65%. The SEM fractography of tensile specimen demonstrates that the BTW1 has significant dimple characteristics and possesses lower-sized dimples with the increment in reduction, suggesting that the toughness and bonding strength of the cladding plates would be improved by the increase of reduction. The results reveal that a high rolling reduction causes the interfacial oxide film broken and further forms a higher-sized composite metallurgical bonding interface. The peak microhardness is achieved near the interface.