焊缝激光跟踪图像处理中关键技术的研究

在焊缝激光跟踪实时图像处理中,采用卷积滤波和中值滤波相结合的方法,提高了中值滤 波能力和处理速度;采用Robert算子,较好地保留了激光光带的边缘;采用左右边界平均值来抽取激光带中心线简单易行;用斜率分析法来检测特征点方便可靠。该图像处理技术效果好能够满足跟踪系统的实时性要求。     

既有房屋增层地基承载力确定方法的分析

根据地基土在既有房屋附加应力的长期作用下,使地基土的孔隙水压力逐渐消散,减少了土的孔隙比,改变了原有土的物理力学性质,提高了原有地基承载力,作为确定既有房屋增层地基承载力的依据,提出房屋增层地基承载力的近似确定方法。并用工程实例加以证实;根据工程实践分析给出预压影响系数与结构刚度影响系数的经验数据,可作为房屋增层设计时参考。     

金属结构焊缝的疲劳设计

本文讨论分析了目前金属结构焊缝的设计方法，介绍了焊缝疲劳设计的方法及公式，提出了提高金属结构焊缝疲劳强度的一些措施。     

2205双相不锈钢的焊接工艺研究

在2205双相不镑钢焊接过程中,通过对焊缝金属和焊接热影响区内金属相变的分析研究,总结出了合理的焊接工艺。     

Seam dip angle based mining subsidence model and its application

The novel mining subsidence prediction model is developed with the dip angle of a bedded ore deposit as a variable. It is applicable for coal seams with a dip angle ranging from 0 to 90°. Application of the model for seams with varying dip angles well demonstrates it's good adaptability.     

A study on a vision sensor system for tracking the I-Butt weld joints

In this study, a visual sensor system for weld seam tracking the I-butt weld joints in GMA welding was constructed. The sensor system consists of a CCD camera, a diode laser with a cylindrical lens and a band-pass-filter to overcome the degrading of image due to spatters and arc light. In order to obtain the enhanced image, quantitative relationship between laser intensity and iris opening was investigated. Throughout the repeated experiments, the shutter speed was set at 1/1000 second for minimizing the effect of spatters on the image, and therefore the image without the spatter traces could be obtained. Region of interest was defined from the entire image and gray level of the searched laser stripe was compared to that of weld line. The differences between these gray levels lead to spot the position of weld joint using central difference method. The results showed that, as long as weld line is within ±15° from the longitudinal straight line, the system constructed in this study could track the weld line successfully. Since the processing time is no longer than 0.05 sec, it is expected that the developed method could be adopted to high speed welding such as laser welding.     

外套加层结构中的隔震支座优化参数研究

对隔震技术在分离式外套框架加层结构中的应用进行了研究,研究结果表明可通过理论表达式得到初步设计时隔震支座的优化参数.采用线性弹簧和线性阻尼器并联的模型模拟橡胶支座,并采用Bouc-Wen模型描述结构的滞回特性.在数值算例中,对不同加速度峰值和不同地震波激励下的外套框架加层结构进行了非线性动力分析,得到了隔震支座的优化刚度和阻尼系数,该结果与理论表达式得到的优化阻尼系数一致,大量的数值分析结果表明在一定范围内,隔震支座的刚度取值对其耗能减震效果影响不大,说明隔震技术在分离式外套框架加层结构中的应用具有较大的优势,隔震支座阻尼系数初步设计值可通过理论表达式求得,可为工程师的初步设计提供参考,有利于这种加层结构体系的推广应用.     

密肋楼板穿线管的敷设问题

密肋楼盖结构楼板薄，而承载力却较大。密肋楼盖的薄板结构虽然在理论上可以满足承载的要求，但是对于数量众多各种暗敷线管的施工却造成了一个不小的难题，针对这一问题，就实际施工中如何对设计图纸进行合理变更，以满足设计及施工规范要求进行了说明，并对今后怎样在设计阶段解决这一问题进行了探讨。     

武汉某大厦结构选型与分析

建筑在结构设计投标阶段,根据业主要求和建筑使用功能、结构体系、技术经济指标等综合因素,对同一建筑物采用三种不同结构体系进行计算比较。最终选用最佳结构体系方案,并在方案中采取了一些特殊的构造措施,如主附楼的高位连体结构设计,沉降差的控制,为控制两楼的扭转局部设置钢支撑结构。通过对不同结构体系的分析研究,可以为其他结构体系定度和方案优化提供参考。     

Investigations of groundwater bursting into coal mine seam floors from fault zones

This paper presents a case study of investigations into retarded groundwater bursting along the fault zones in the seam floors in coal mines. In addition to in situ measurements of ground stresses, a number of rock samples from the fault zones at the site of the case study were taken, and laboratory tests were performed for conventional and special rheological rock mechanics properties. The effects of different parameters on deformation and failure of the fault zone materials were analyzed, and the mechanism of retarded groundwater bursting along fault zones was further revealed. In the case study, different scenarios accounting for the different development phases of the fault weakness zone and groundwater bursting as well as different groundwater pressures were considered, and each of them was simulated using the 3D visual elastic–plastic numerical mechanics model FLAC^3D (Fast Lagrangian Analysis of Continua in 3 Dimensions). Through the case study, the applicability of rock mechanics modeling software for studying retarded groundwater bursting along a fault zone was examined. Several issues are discussed regarding the investigations of retarded groundwater bursting and a general structured approach to investigate and control this geological hazardous event is presented.