广州新白云国际机场地基处理工程研究——高压注砂浆与袖阀管注浆相结合方法

广州新白云国际机场地基中广泛发育土洞、溶洞等不良工程地质现象，地基条件极其复杂。为保证构筑物的安全，在土、溶洞处理工程中采用了高压注砂浆与袖阀管注浆相结合的施工方法，通过对施工方法与技术要求的总结，归纳了质量控制要点，并概述了施工中容易出现的问题并提出处理措施。采用高压注砂浆与袖阀管注浆相结合的工艺，即加快了工程进度，降低了工即程造价，又达到预想的效果。     

五里冲水库--治理和利用喀斯特溶洞的范例

滇南蒙自五里冲水库，系充分利用盲谷地形、地下隐蔽喀斯特大厅、地下暗河等自然条件，扬长避短，通过明堵暗灌、高压灌浆、构建防渗帷募等特殊综合工程手段建造的无大坝型水库。该区地质情况复杂，喀斯特十分发育，先后投入大量钻探、平硐及基础地质调查工作量，采和合适的防漏、防渗工程。1996年竣工下闸蓄水后水位持续上升，达到设计要求，为蒙自工农业经济发展提供条件，亦为在我国南方复杂喀斯特地区构建大、中型水库闯出新路。     

山西五台县水泉湾泉和李家庄泉的成因分析

本文主要根据水泉湾泉和李家庄泉泉域的地质和水文地质资料，分析了本区内岩溶的发育特征和岩溶地下水的循环规律．研究分析了水泉湾泉和李家庄泉的形成原因。     

Treating the Risks in Cairns

Cairns is exposed to the well-known natural hazards oftropical cyclone, flood, stormsurge and thunderstorm, but is also exposed to thelesser-known hazards of landslip, earthquake and dam break flooding. Recommendations fortreating the risks associated with these hazards have been made that will involve amulti-disciplinary approach to treatment strategies, require the cooperation of allthree levels of government, involve public utility authorities and private enterprise andinvolve the community as a whole.This paper summarises the suggested mitigation treatmentoptions, presented to the Cairns City Council and identified in the LocalGovernment Disaster Mitigation Project conducted in Cairns in 1999/2000 by theQueensland Department of Emergency Services.     

真空-堆载联合预压处理软基效果的室内试验研究

对甬-台-温高速公路采用真空-堆载联合预压处理软基前后的土样进行了室内试验分析,得出了合理的试验结论,即土的物理性质指标分别得到不同程度的降低,强度指标得到较大的提高。     

岩溶浸没－内涝灾害研究

水库周边岩溶浸没-内涝现象是水利水电设计的环境问题之一。80年代以来,已在若干水库发生了此类现象,造成了一定的经济损失,本文以红水河岩滩水电站库区的内涝为例,分析了岩溶浸没内涝的主要原因和形成条件,归纳为降雨、管道、水库三要素。讨论了岩溶浸没-内涝灾害的预测及对策。     

The fountains of Pretoria

The occurrence of groundwater in South Africa is to a very large degree limited to a surficial zone of weathered and fractured hard rock formations. Primary aquifers include narrow strips of alluvium along certain river stretches and to Cenozoic coastal deposits. Coupled with a rainfall that is well below the world average, South Africa is therefore poorly endowed with large springs. These are almost totally confined to karst areas.     

Vegetation change,erosion risk and land management on the Nullarbor Plain,Australia

 Arid karst landscapes that have been degraded by human activities provide a challenge for rehabilitation and an opportunity to test ideas about the stability and resilience of limestone ecosystems. The Nullarbor Plain is the largest arid karst area in Australia (220 000 km²) and is divided into extensive closed karstic depressions separated by low rocky ridges, while the dominant vegetation is chenopod shrubland. Since European settlement there has been considerable change in the vegetation, with significant reduction in shrub and grass cover over large areas of the plain. These changes are related to a state and transition model of vegetation dynamics which incorporates climatic variability, fire history and grazing pressure from sheep, kangaroos and rabbits. A partial sediment budget using ¹³⁷Cs inventories reveals local and regional patterns of soil redistribution within this arid karst landscape. Rehabilitation of eroded soil in pastoral lands has been accomplished at several sites but is labour intensive and vulnerable to climatic fluctuations. Given the low stock numbers, limited number of people involved, and poor economic returns, it would be sensible to make pastoral activities on the Nullarbor secondary to conservation priorities. This would necessitate a change in land ethic to stewardship, with emphasis on rehabilitation and control of feral animals. Management of increased numbers of visitors to the caves and karst also requires that resource inventories and management plans for each area be drawn up and used. Received: 1 June 1995 · Accepted: 4 December 1995     

Utilization of lime,slag and fly ash for improvement of a colluvial soil in New South Wales,Australia

In Australia, colluvial soils form large terrains which are often subjected to considerable erosion and mass movement. This study presents a laboratory evaluation of the improvement effected by hydrated lime, milled blast furnace slag and fly ash on a fine grained (erosive) colluvial soil in New South Wales, Australia. Geotechnical tests were conducted to determine the compaction and consolidation characteristics and the compressive and shear strength properties of the blended and natural soil specimens. The effect of these additives on the Atterberg limits and pH levels is also investigated. As large amounts of fly ash and steel slag are produced in New South Wales, it is economically attractive to utilize these industrial by-products for ground improvement rather than employing conventional methods such as lime treatment. This study demonstrates that for the colluvial soil tested, milled slag is the most effective in terms of improving the internal friction angle of the treated soil, while lime is the most suitable for achieving the optimum compressive strength. Non-pozzolanic fly ash is found to be inappropriate as a soil improving agent. The cost of ground treatment using the various additives is also estimated and compared.     

Paleocollapse structure as a passageway for groundwater flow and contaminant transport

 Paleocollapse structure is a rock collapse, resulting from the failure in the geological history of the bedrock overlying karstified limestone. Depending on the present hydrogeological conditions within the area of paleocollapse and the internal properties of these structures, they can provide a means to facilitate groundwater flow and contaminant transport. Inactive paleocollapse structures can be reactivated by human activities such as dam construction, mining underground minerals, pumping groundwater, and development of landfills. They can also be reactivated by natural events such as earthquakes and neotectonic movements. In the mines of northern China, sudden inflow of karst water from Ordovician limestone into drifts and mining stopes through paleocollapse structures has caused significant economic loss. Water pumping tests and accompanied dye traces are effective approaches of locating water-conducting paleocollapse structures. Grouting is probably the best means of preventing them from becoming geohazards. Received: 26 November 1996 · Accepted: 17 June 1997