【摘要】 交河故城遗址是第一批全国重点文物保护单位,瞭望台是交河故城内重要建筑遗址,它的主要病害是表面风化、裂隙密布、洞顶失稳。在分析病害形成机理的基础上,重点研究了生土遗址保护加固的几个关键技术,对掏蚀深度相对于悬挑土体厚度较小的土遗址,当基础掏蚀深度小于块体宽度的30%时,可不采用砌补技术,只进行表面防风化处理;可选择竹木锚杆、PS-C浆液灌浆加固生土遗址,锚杆的单位锚固力可采用5kN/m;采用新奥法加固洞顶可较好地保持文物原貌;西部干旱地区采用PS材料对土遗址进行防风化加固时应采用低浓度(小于5%)、多次渗透的方式,迎风面渗透次数应不少于3遍,背风面应达4～5遍,并应合理选择施工时间。工程实践检验表明,这些保护技术取得了理想的加固效果。更多还原

【Abstract】 The Ruins of Jiaohe is a national major preservation unit of cultural relic. As an ancient earthen city site, it is more intact and biggest in the world currently. The Observation Platform is a major and typical building in the Ruins of Jiaohe. The primary damages of the Observation Platform include surface weathering, unstable roof of cave and many crannies. Based on analysis of the damages forming, some key techniques of protection and reinforcement of earthen site have been studied. It is suggested that when the depth of base recess is less than 30 % the width of the block and is very smaller than thickness of cantilever block, it should not be repaired and only used the method for preventing surface weathering. With bamboo-wood anchor and PS-C grouting, the anchoring unit power of wood can be adopted 5 kN/ m by test. NATW, the technique for reinforcing the roof of cave, can acquire effective result for preserving its appearance. In the arid region of western China, when applying PS material to reinforce ancient earth-structure sites and prevent the surface weathering, we should adopt low density (smaller 5 %) of the PS, and the method of many times penetrating. The number of permeating should not be less than 3 times in windward side, and should amount to 4-5 times in leeward side. The reasonable working-time needs choice. By the examination of engineering practices, ideal result has been obtained after applying these protective techniques.更多还原