1975年原一机部设计单位屋面防水调研组对一机部系统单层工业厂房屋面防水进行了重点调研工作。油毡屋面防水使用情况及共寿命年限概要归纳如表1所示。一、卷材屋面存在问题及危害性从表1可以看出油毡屋面产生的裂、淌、鼓、老、漏等问题的普遍性,而漏是裂、鼓、淌、老的结果。其损坏情况如表2、表3所示。从表3可以看出:①沿屋架横缝、天沟、雨水口三个部位渗漏最严重,占调查车间总数50％以上;其次是女儿墙、山墙及檐口等部位,渗漏占29～42％;伸缩缝、沉降缝、天窗渗漏等约占19～30％。②沿屋架横 In 1975, a research team for the roof waterproofing department of a unit design department conducted a major survey on the waterproofing of the roof of a single-layer industrial plant. The linoleum roof waterproofing situation and the total life span are summarised in Table 1. 1. Problems and Harmfulness of Coiled Roofs From Table 1, it can be seen that the lining roofs are generally cracked, flawed, bulging, old, and leaky, and the leakage is the result of cracks, drums, squatting, and oldness. The damage is shown in Table 2 and Table 3. From Table 3, it can be seen that: 1 The leakage is most serious along the three parts of the truss transverse joints, gutters, and rainwater outlets, accounting for more than 50% of the total number of workshops surveyed; followed by parapets, gables, and cornices, and leakage accounts for 29%. 42%; expansion joints, settlement joints, sunroof leakage, etc. accounted for about 19 to 30%. 2 along the truss