矿床地质特征对采矿方法选择的影响研究外文翻译资料

英语原文共 15 页，剩余内容已隐藏，支付完成后下载完整资料

英文翻译

The satisfactory design and construction of an engineering structure can be accomplished only when the character of the soil or rock, on which or within which it is to be built, is known. For this knowledge to be obtained the ground must be carefully studied by investigations conducted in-situ. Engineering structures such as roads, dams, buildings, tunnels and other underground works, are normally constructed according to the requirements of a specific design and from selected construction materials: by observing these requirements the strength of the completed structures is known and their response to load and displacement may be predicted. To obtain comparable information about the soil and rock against which the structure will react it is necessary to understand the geological processes which formed the soils and rocks, this being the only way to reveal their design, and the nature of the materials of which they are composed.

工程结构的令人满意的设计和构造只有在已知土壤或岩石在其上或在其内建造的特征时才能实现。 为了获得这种知识，必须通过原位调查仔细研究地面。 工程结构如道路，水坝，建筑物，隧道和其他地下工程，通常根据特定设计的要求和选定的建筑材料构造：通过观察这些要求，已知完成的结构的强度及其对负载的响应 并且可以预测位移。 为了获得关于结构将反应的土壤和岩石的可比信息，有必要了解形成土壤和岩石的地质过程，这是揭示了这种所谓“设计”的唯一方式,以及材料组成的性质。

Approach

A common difficulty with ground investigation is that most of the ground will remain unseen, but this does not mean that the ground need remain unexplored.

Figure 10.1 illustrates a site considered for a dam: 3% of the foundation rock is naturally exposed and can be seen (Fig. 10.1~).Bore-holes and trenches increase the

Fig. 10.1 A comparison between the volume of ground affected by a structure and the volume investigated.

visible evidence by less than 1% (Fig. 10.lb) and geophysical investigations, which do not produce visible evidence but merely physical responses that are characteristic of certain ground conditions, assist the extrapolation of visible evidence to other areas. Volumes of ground can be tested in- situ (Fig. 10.1~)and much smaller volumes, collected as bore-hole core, can be tested in a laboratory. With these data the basic design of the dam is completed and costed. Further investigations may be undertaken if the scheme is feasible but even with these studies construction will commence with only a small fraction of the ground having been seen. As the foundation rocks be-come exposed during construction (Fig. 10.ld) unforeseen ground conditions may be revealed and require further investigation.

There is no agreed approach to ground investigation which may vary from the repetitive programme such as one bore-hole every I.Okm along the centre line of a road, to the carefully considered exploration that is tailored to site geology and its likely interaction with the engineering structure. Codes of practice exist, which if followed ensure that the methods used in investigation are conducted with an appropriate standard of confidence. They may also advise that certain works be under-taken, such as the excavation of inspection pits, but can-not indicate where best to site them. For this, geological advice is required. The use of probability theory has been considered as an aid to defining an approach to ground investigation, but such theory assumes a know-ledge of the geological processes that formed the site, and that is one of the topics the ground investigation is meant to reveal.

方法

地面调查的一个常见困难是大部分地面仍然是看不见的，但这并不意味着地面需要仍然没有被探索。

图10.1显示了一个考虑用于大坝的场地：3％的基岩是自然暴露的，可以看到孔洞和沟槽增加了.

图10.1受结构影响的地面体积与所研究体积之间的比较。

可见证据小于1％（图10.lb）和地球物理调查，这些调查不产生可见的证据，而仅仅是某些地面条件所特有的物理响应，有助于将可见证据外推到其他地区。体积的地面可以在现场测试和小得多的体积，收集作为钻孔核心，可以在实验室测试。利用这些数据，完成了坝的基本设计并计算了成本。如果该计划可行，则可以进行进一步的调查，但这些研究的结构只有一小部分从已经看到的地面开始。随着基础岩石在施工过程中暴露（图10-11），可能会暴露出未知的地面条件，需要进一步调查。

没有商定的地面勘探方法，这可能与重复程序有所不同，例如沿着公路中心线每一公里一个钻孔，到仔细考虑的勘探，这种勘探是针对现场地质及其可能的相互作用与工程结构。存在实践守则，如果遵守，确保调查中使用的方法以适当的信任标准进行。他们还可以建议某些作品被采用，例如挖掘检查坑，但不能指明在哪里最好地放置它们。为此，需要地质建议。概率理论的使用被认为是对定义地面调查方法的辅助，但是这种理论假设了形成地点的地质过程的知识，这是地面调查旨在揭示的主题之一。

Content

Table 10.1 lists five factors that must usually be investigated by every ground investigation. It is therefore useful to ascertain for a site the information already available for each of these factors before commencing further exploration as this will reveal the topics for which insufficient data exists and which must be the subject of further study. To anticipate conditions that might otherwise re-main unforeseen it is relevant to consider the geology of the region. For example when it was raised above sea level, how rapidly it has been eroded, the depth of weathering, the likely depth of bedrock in valleys filled with alluvium or colluvium, the possibility of stress relief structures in the valleys and of fossil landslides on the valley sides. Many unforeseen problems can be attributed to a ground investigation that has been too restricted in its approach.

Programmes of ground investigation should be flexible in content and phased in execution. Flexibility enables investigation to be amended when unexpected features of importance are encountered. As shown in Fig. 10.1 it is unlikely that every geological feature of note will be revealed prior to construction and a phased investigation permits later studies to be completed. Table 10.2 illustrates an example of a phased investigation.

Cost

The cost of most ground investigations is between 0.5% and 1.0% of the cost of the project but this should not be taken as a rule. The principal purpose of ground investigation is to acquire geological and geotechnical data sufficient for the geology of the site to be described and its geological history to be reconstructed, particularly those events occurring during the past 10 000 years, with an accuracy that can be relied upon by design and construction engineers. If the ground is complex, appropriate funds should be made available for its investiga

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