Sustainable Campus Summer‧Autumn 2008

Safe, Green and Beautiful Slopes of the Chinese University ݷ¥Ļ£ǽڿ̵ֲġַɾֲ ľִֹʱϳ A more time-consuming method of stabilizationtrench excavationwas used to stabilize this fill- slope near the Lady Shaw Building so tree removal can be minimized. Part of the procedure was carried out manually. ʮڳְԱḽ໤б£ͼͬһбµòͼ Before: a slope covered with chunam plaster near Chung Chi staff quarters in the 1990s (top) After: the same slope now (above) ·ݣϮ̨ۡ꼰ɽ к档ܴһ ʴд¼ɽкһٷǼ б¼ȻбµУ԰˵ijɼʵڵ סܺɫת磬бѱï̡⵱ ȻҲǵ׵ġб¼ȰȫĿǾ ϤĸƵijɹ ȫ 1997꣬ܵĺ꣬ У԰ּ ɽк ֮ɽкĴֱ2000꣬ʹ 꼾ҲֻмĴģơ鹦 1998У԰ίԱߣԼУ԰ չҵŬЩԱר ҵʿ˵ȫҪģŬ б¹̺ľ۴ б¹̺ھ۴ϴ¿ɷΪ੤Ӳ 档Ӳ洦б°͸ܰ ϣҴǽʮۣ бºDZҪڿ ١˼Чַ㷺ʹá һɽɫҽ ܡɽԭл ǷȱЭּ ΣбµĽ slopes include slopes sprayed with concrete, rock outcrops and retaining structures. In the 90s, shotcreting (projecting concrete through a hose onto a surface) was the dominant method of surface protection after slope stabilization in Hong Kong. Quick, cheap and effective, it was widely used by the Government. But the shotcrete nozzle is a Vesuvius that mummifies everything within its radius with a layer of white lava. Shotcreted hillsides look lifeless and incoherent. So while the technique was still used to treat dangerous slopes and as an emergency measure, the University shifted its focus to methods that would bring more aesthetically pleasing results. Cosmetic Approaches Over the years, the University has adopted an array of techniques to mitigate the visual impact of engineering works and maximize opportunities for vegetation planting on slopes. Examples include the planting of ornamental shrubs and climbers on slopes and retaining walls, the use of earth-toned masonry facing, and adoption of advanced greening technologies such as mulching. Protection of Trees Contrary to common belief, trees do not necessarily have to be removed during slope improvement works. At the University campus, for instance, soil nailing is used to stabilize cut-slopes in order to reduce disturbance to trees, and where the slope surface has to be regraded, tree rings and toe walls are sometimes used to retain trees. Sometimes trench excavation, a more time-consuming and partiallymanual method of stabilization is used to stabilize loose fill-slopes in order to minimize the need for tree removal. Slope improvement is an ongoing process. Untreated slopes have to be made safe while stabilized slopes have to be closely monitored and maintained. Admittedly though not all greened slopes resemble the Garden of Eden in bloom, at least not all the time. The state of the vegetation depends also on the conditions for growth. But given that this is science trying to mimic nature, the University has fared very well, said Mr. Arthur Ma, geotechnical engineer in the Campus Development Office. Adrive down Taipo Road outside our gates would tell you that. ʩѧʹЧ Ŀ ѧø̵ּӾЧ бֲӰбº͵ǽ ֲװõĹľԵֲʹúɫʯ棬 縲ݷȽ̻ ľ һΪб¸ƹһҪľʵ Ȼ˵дУ԰ඤȶ£ ľб±棬ʱѨ ½ǽľһǽڿȶɢ Ļ£ֲľʱϳֹ ִ бάϡȻбҪðȫ ȫб±мͱȻ ̻б¶԰ïʢٲ ʱ̡У԰չʦά±ʾ ֲ״̬ȡĻģȻ ϣѧ÷dzɫݳѧ ĴҵɼԷ顣 ̻Ŀдб