亮视点眼镜官网:Environmental Geology of Limestone in Malaysia 5

原文
3.3 Cavities in limestone bedrock
Cavities in the limestone bedrock are of major concern to foundation engineers. They occur at various depths, i.e. in multi-levels, and are of various sizes/thicknesses. A survey of cavity sizes based on borehole data in the Ipoh area showed that they are mostly < 3 m in thickness (Table 2, Tan, 1988). Ting (1985) and Ting et al. (1993) also concluded that the most common cavity size is < 1m. In any case, occasional large cavities >3 m can still be encountered at a particular site.
Thus, the detection and determination of the detailed configuration of the cavities and cavity system at a particular construction site are major efforts in a site investigation programme, in particular where high-rise buildings are being planned and constructed. Three dimensional physical models have been used to depict and decipher the intricate nature and extent of the cavities and the bedrock profile.
A recent high-rise project in the K.L. area witnessed the tremendous efforts put in to detect the cavities in the limestone bedrock by employing > 100 boreholes on a close-grid boring pattern. Numerous cavities, some at multi-levels, were detected through those efforts. The number of boreholes for high-rise buildings underlain by limestone bedrock are in the order of 100's, e.g. the Petronas Twin Towers have ~400 deep boreholes (Tarique Azam, 1996).
The formation of cavities in the limestone bedrock is related to the fluctuations of
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the groundwater level. Cavities are developed mostly within the zone of groundwater level fluctuation, and it is reasonable to expect that deeper down below the zone of active groundwater fluctuation, cavity formation would be limited. The exposures at the Bandar Sunway Quarry (bedrock) seem to support such an idea that below a certain depth the limestone bedrock is massive (although jointed) without cavities or other solution features. Nearer the surface, large cavities, solution arches, pinnacles etc. are observed.
For the K.L. region, it would be reasonable to postulate that below a certain Reduced Level (RiL), the limestone bedrock would not contain any cavities. The determination of this R.L. would require a meticulous compilation of all borehole data in limestone in the K.L. region--something that has not been attempted to date!
Fig. 3 illustrates the development of cavities/caves in relation to limestone hills as suggested by Wilford (1964), which is perhaps also applicable to limestone bedrock.
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译文
3.3 在石灰石岩床中的洞
在石灰石岩床的洞是主要关心对基础工程师。 他们在各种不同的深度发生,在多水平中也就是, 而且是各种不同大小/厚度。 在 Ipoh 区域中以在地上凿穿的洞数据为基础的一个洞大小的调查表示他们大概是厚度的 <3 m 。 (表 2 ，鞣制革,1988) 铃的响声 (1985) 和铃的响声以及其他人。 (1993) 也得出结论最通常的洞大小是 <1 m 。 无论如何，偶然的大洞 >3 m 能仍然在一个特别的位置被遇到。
因此，在有多层的建筑物正在被计画而且构造的个别项目中,洞的详细结构和洞系统的发现和决心在一个特别的工程位置在位置调查节目中是主要的努力。 三个空间的实际模型已经用来描述并且译解复杂的自然和洞和那岩床描绘的范围。
在 K.L. 区域的一个最近的有多层的计画目击了被提出藉由雇用在石灰石岩床中发现洞的巨大的努力 >100个在地上凿穿的洞在一个结束上-格子无聊的式样。 很多的洞, 一些在多水平, 被发现过那些努力。石灰石岩床的有多层建筑物 underlain 的在地上凿穿的洞的数字在 100 年代的次序中, 举例来说 Petronas 生双胞胎 , 塔有 ~400个深的在地上凿穿的洞.(Tarique Azam,1996)
在石灰石岩床的洞的形成被讲到变动
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地下水消除。洞在地下水水平变动的地域里面被大概发展，而且期待在活跃地下水变动的地域下面是向下的那比较深者是合理的,洞形成会是有限。 暴露在恒河猴 Sunway 挖出 (岩床) 似乎支援如此的一主意以致于在特定的深度下面，没有洞，石灰石岩床很巨大的 (虽然有接缝的) 或者其他的解决扮演重要角色。 更接近表面又大的洞，解决拱门, 高峰等等被观察。
对于 K.L. 区域，在一个确定的减少水平 (RiL) 下面要求那会是合理的,石灰石岩床不包含任何的洞。 这 R.L. 的决心会在 K.L. 区域中的石灰石需要一个所有在地上凿穿的洞数据的一丝不苟编辑--没有被尝试约会的某事!
图 3 关于如 Wilford(1964) 所建议的石灰石小山举例说明洞/洞的发展, 这是也许也适用于石灰石岩床。
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