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　　北京新航道学校致力于雅思培训为大家提供权威参考资料。暑假已经结束了，赶在这个时间参加雅思的考生朋友们也完成了自己的学习计划，总结这个暑期的阅读试题，我们为大家进行了整理，希望对那些正在准备考试同学有所帮助。雅思阅读对于国内考生来说难度较大，除了专业水平之外，还极度考验着同学的耐心和细心。下面就给大家一些资料，希望对于同学的英语成绩有所帮助。

　　本期为大家整理的阅读试题比较多，一部分练习的题目会跟在下面一篇文章中，请同学们知悉。

　　主要内容是公司在施工的时候经常会对各种已经有的设施和结构进行相关的处理。那么这样做需要有什么准备吗?需要通过什么步骤来实施呢?下面就是相关信息。

　　Geophysics For Utility Location: When It Works - When It Won’t

　　Utility companies, construction projects, and highway contractors are often faced with the need to excavate or pipe-jack in the vicinity of known or suspected buried utility lines, drains, or other subsurface structures. In many cases, particularly where they are adjacent to highways, the lateral position of the lines may be documented with reasonable accuracy, but the vertical position, or burial depth, may be uncertain due to changes in grade caused by construction or maintenance performed after the pipes were buried.

　　One way to verify the location of such buried objects is to cautiously dig a trial pit to expose the object in question. However, digging such a pit in or close to a highway is costly because of the need for traffic control, and subsequent reinstatement of the surface to meet the original specification. There is also a substantial risk of accident and personal injury, partly due to the disruption caused to the highway traffic, and partly due to the nature of the work. Where mechanical digging equipment is used, an undocumented or misaligned utility line can easily be damaged if the excavation workers do not observe it. Gas and electricity lines present very obvious safety threats in this situation.

　　These factors have caused utility engineers and contractors to search for alternative methods to locate subsurface structures, often with mixed success. There are several geophysical techniques with proven capabilities in non-intrusive subsurface investigation, but there are less publicized limitations to these methods that potential specifies and users should be aware of if they are to avoid inconclusive or misleading survey reports.

　　Practical Near-Surface Techniques

　　The real driving force behind the development of geophysical survey methods was the search for oil and other valuable mineral deposits. The earlier methods were therefore primarily focused on the detection and identification of relatively large geological formations at depths that were typically measured in several hundreds of feet. Such methods do not have the resolution to detect small objects, such as pipelines and cables, buried only a few feet deep.

　　A few methods, however, were either developed specifically for near-surface work, or were readily adaptable to the task of locating relatively small objects at shallow burial depths. The most commonly used methods in current utility location practice are:

　　· Ground Penetrating Radar

　　· Magnetometer/Gradiometer

　　· Non-contact Conductivity

　　· Specialized Utility Locators

　　These methods have been proven to be very effective in the right conditions, but all have limitations that can render them inconclusive, or worse still, misleading, if used or interpreted by an inexperienced operator.

　　经过老师课堂经验发现，雅思阅读对考生来说就是不能合理分配阅读题干的时间和答题时间，这还需要同学在平日里多加练习，以便应试速度，老师提醒大家，成绩绝非一朝一夕之事，勤奋练习才能收益。最后祝你考试顺利。

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