Spiralnails are hollow steel pipes extruded and twisted to form a square helical shape. They are driven rather than drilled, and thus they do not require cement grout to develop a bond with the soil, and provide immediate internal stability improvement to a soil mass. Because effective and economical designs require an improved understanding of individual and group spiralnail behavior, a 6-m (20-ft) tall, top-down vertical excavation was constructed using spiralnails in a well-characterized, engineered fill. The spiralnail reinforcement design used existing soil nail design methods to achieve an acceptable factor of safety using nail lengths and spacing comparable to those common for a conventional grouted nail design. The objective of the project was to measure the performance of the spiralnail reinforced soil mass in order to evaluate the applicability of existing soil nail design methods to spiralnail design. The paper describes the design, construction, soil characterization and properties, instrumentation, and presents the measured load-displacement behavior of the spiralnails and observed deformation of the reinforced soil mass. A preliminary analysis of load-displacement data is presented, and calculated spiralnail equivalent bond stress values are provided. Based on the measured deformations and using an empirical correlation, the spiralnail-reinforced soil mass performance is compared to a grouted nail-reinforced soil mass.

关键词：钢管挤压；钢铁；荷载位移数据

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Driven piles are subjected to high stresses during installation. It is, therefore, important not to exceed acceptable stresses along the pile shaft and at the toe to prevent damage. Dynamic monitoring has been used for decades to evaluate not only the installation stresses, but also check test piles for signs of structural damage. The Beta Method (?-Method) for evaluation of the location and extent of a potential damage was developed over thirty years ago and has proven effective as a QC and QA tool. As an aid in the process of pile rejection or acceptance, the ?-Method also offers a rating scale which translates the automatically determined ?-number into a helpful pile integrity assessment tool. The reliability of this algorithm has been proven by numerous extracted piles. However, one limitation of the ?-method concerned detection of damage near the pile toe where high toe resistance effects and/or stress wave reflections reduce the effectiveness of the traditional ?-Method. In the past, therefore, near-toe damage was determined by the testing engineer, not only by visual inspection of the dynamic monitoring data, but also by reviewing the pile toe compressive stresses throughout the monitored driving history and the strength and stiffness of the soil response from the pile toe. This approach has now been automated and subjected to tests on existing data. After a review of the existing methods of pile stress and damage calculations, the paper presents the new method, illustrating its effectiveness by examples from measurements on both concrete and steel piles.

关键词：打入桩；钢铁；动态监测

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A data base of 84 pile load tests was developed for steel pipe piles, driven in clay (small amounts of sand near the surface for a few tests), where there was sufficient data to estimate effective overburden pressures with reasonable accuracy, where soil strengths were well defined, and where a load-settlement curve was available for the load test. Measured pile capacities were compared with values predicted using five methods that have been, are being, or potentially may be used in engineering practice. The two lambda methods had the least scatter but tended to overpredict capacities by about 20%. The current API method had slightly more scatter but overpredicted capacities by only about 13% on the average. The two alpha methods had the largest scatter and the greatest differences between measured and predicted capacities.

关键词：荷载试验；钢铁；负载沉降曲线

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The flutter stability of the steel truss suspension bridge is hard to reach the requirement of the wind resisting stability when lacks the torsional stiffness.This paper discusses the influence of aerodynamic measure combination,such as central stabilizer,air director enclosed anti-collision bar and so on,towards the flutter stability of steel truss through the wind tunnel experiment of the bridge of Liu Jia gorge.The result shows:the effect of using both the upper and lower stabilized plate is better than separated used it.when sectionalized dispose upper stabilized plate,the flutter critical wind speed of attack angle will decrease rapidly.Outlaying the horizontal guide plate is better than internally installed; The flutter stability of different attack angle tend to be balanced by widening the horizontal guide plate.The anti-collision bar can be functionalized as the central stabilizer by heightening and enclosing,and effectively increase the critical wind speed of different attack angles of the high truss suspension bridge.

关键词：悬索桥；风洞试验；抗风措施；钢铁

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To develop an effective software for finite element (FE) model updating of bridges, the interface technology between VC++ and MATLAB was investigated firstly, and then a software for updating FE model of bridges, named 'Doctor for Bridges' (version 1.0) was developed. Finally, a model ofconcrete-filled steel tube arch bridge was applied to verify the performance and effectiveness of the proposed software.

关键词：桥梁；有限元模型修正；接口技术

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The Health Hazard Evaluation Program received a request from the manager of a federal government office complex. Employees were concerned about health problems including cancer, gallbladder problems, and chronic obstructive pulmonary disease. Some employees believed their health problems were associated with contamination of the buildings, soil, and groundwater from an adjoining weapons component manufacturing agency. The entire complex consisted of 13 buildings with the largest structure at the site containing over 1 million square feet across three floors. This structure contained two main areas: (1) Buildings 1 and 2 (office and warehouse space where most of the complex's employees worked) and (2) the weapons component agency. A floor-to-ceiling fire wall physically separated Buildings 1 and 2 from the weapons component agency. We reviewed environmental sampling records, did a visual inspection of Building 1 and 2 ventilation systems, spoke with employees about their health. We also tested former and current employees with sarcoidosis (an inflammatory disease that is nearly identical to chronic beryllium disease) for sensitization to beryllium, which was used for weapons manufacturing. Our evaluation found (1) no reports of employee overexposures to volatile organic compounds, polychlorinated biphenyls, beryllium or other metals, solvents, formaldehyde, or radon; (2) no evidence of beryllium sensitization among 22 persons tested; and (3) no cancer excess or abnormal pattern of disease. We noted that (1) Buildings 1 and 2 have separate ventilation systems from the weapons component agency and (2) potentially contaminated exhaust air from the weapons component agency was unlikely to enter the outdoor air intake(s) for Building 1 and 2. We recommended the employer encourage employees to learn about their personal cancer risk factors and educate employees on what they can do to reduce their risk for cancer. We also advised the employer to stop all investigations of cancer incidence and routine air and surface wipe sampling for chemicals.

关键词：大气；空气污染；健康

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The Auger export pipelines are connected to the TLP by steel catenary risers (SCRs). This is believed to be the first time steel pipe has been used for catenary risers. SCRs offer advantages over tensioned risers, since SCRs need no heave compensation and no subsea connections, and over risers made of "flexible pipe", since SCRs are much less expensive. However, significant design effort was required to prove that the SCRs could safely withstand environmental loads and the effects of TLP motions. The design effort consisted of extensive dynamic analyses as well as full scale fatigue testing of both the riser joint welds and the flexible joint that connects the riser to the TLP pontoon. Devices which suppress vortex induced vibrations were also tested. SCR installation is accomplished by lowering the riser on the abandonment and recovery cable from the J-Lay installation vessel and transferring the riser on a chain that is run through a chain jack hung from the TLP upper deck structure. A special Installation and Maintenance System was built for this purpose.

关键词：出口管道；立管接头焊缝；钢铁

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The Universal Breakaway Steel Post (UBSP) was developed and evaluated to replace the existing Controlled Release Terminal (CRT) wood posts which were used in the original bullnose guardrail system. Previously, three full-scale crash tests were performed on the thrie beam bullnose barrier with UBSPs, and the UBSP was determined to be a suitable alternative for the CRT posts. However, the UBSP was modified prior to the completion of the full-scale tests, and dynamic component testing was not conducted to compare the post behaviors. Therefore, a series of nine component tests were conducted in soil to compare the weak- and strong-axis properties between the UBSPs and CRT posts. As part of the component testing, one of the weak-axis tests involving the UBSP was conducted with a reused lower section of the post; since, the original development of the UBSP recommended reuse as long as the lower section was undamaged and displaced less than 12 in. (13 mm). From the testing series, it was determined that the performance of the UBSP indicated a strong potential for these posts to be utilized in other applications. However, UBSP should first be evaluated through engineering analysis and full-scale crash testing before implementation.

关键词：碰撞测试；动态测试；护栏岗位；钢铁

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We consider a cutting problem, which have a practical application. In this problem, items are being cut from larger items, for example textile patterns from a panel of cloth. We deal steel tubes of given length, which have to be sawed from longer steel tubes. These longer steel tubes come with given costs and the sawing has to be planned such that the total costs are minimized.

关键词：切割的问题；一维；吉尔摩和戈莫里方法；钢铁

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The objective of this research is to evaluate the feasibility to employ quantitative acoustic emission (AE) techniques for monitoring of fatigue crack initiation and propagation in steel bridge members. Three A36 compact tension steel specimens were tested in the laboratory according the ASTM E647. AE sensor networks were deployed and recorded AE during the fatigue-type loading. Noise from the load application points represented a significant challenge. However, a number of events could be located and for a selected few a moment tensor inversion (MTI) was performed. Despite the challenges, the methodology has been completely established and evaluated, and can be used in future testing.

关键词：声探测;桥梁（结构）；裂纹扩展；裂纹（断裂）

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