岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
1期
273-278
,共6页
大直径薄壁钢管%污水管道%数值模拟%影响评估
大直徑薄壁鋼管%汙水管道%數值模擬%影響評估
대직경박벽강관%오수관도%수치모의%영향평고
large diameter thin-wall steel pipe%sewage pipe line%numerical simulation%impact assessment
城市内新建工程周边环境复杂，地下管线种类繁多，在设计之初就需要考虑施工以及工程营运对其安全的影响，但目前缺乏统一的影响评价标准，须按照管线功能以及所属部门的相关规程作为其评价依据。该项目的管线为下穿围堰的2条直径为1.2 m、壁厚为12 mm的排污管，采用FLAC3D建立了围堰工程对大直径有压焊接薄壁排污管道的三维数值计算模型，分4种不同施工工况进行了管道变形和应力计算。依据相关规范的要求，从管道本身的安全性和正常使用要求出发，并采用第4强度理论计算了相当应力，最大值为136.61 MPa，出现在最后抽水工况下管1的外侧。最大沉降量39.3 mm对应的管体倾斜量为0.275%。将其结果与理论值进行对比，理论计算得到的相当应力最大值为188.18 MPa，高于数值计算结果，其原因为理论方法将各影响效应分别计算并进行简单相加。结果表明，拟建围堰工程对该管线的影响可控，数值方法较规范方法计算结果更为合理，为类似工程对管线影响评价提供了参考。
城市內新建工程週邊環境複雜，地下管線種類繁多，在設計之初就需要攷慮施工以及工程營運對其安全的影響，但目前缺乏統一的影響評價標準，鬚按照管線功能以及所屬部門的相關規程作為其評價依據。該項目的管線為下穿圍堰的2條直徑為1.2 m、壁厚為12 mm的排汙管，採用FLAC3D建立瞭圍堰工程對大直徑有壓銲接薄壁排汙管道的三維數值計算模型，分4種不同施工工況進行瞭管道變形和應力計算。依據相關規範的要求，從管道本身的安全性和正常使用要求齣髮，併採用第4彊度理論計算瞭相噹應力，最大值為136.61 MPa，齣現在最後抽水工況下管1的外側。最大沉降量39.3 mm對應的管體傾斜量為0.275%。將其結果與理論值進行對比，理論計算得到的相噹應力最大值為188.18 MPa，高于數值計算結果，其原因為理論方法將各影響效應分彆計算併進行簡單相加。結果錶明，擬建圍堰工程對該管線的影響可控，數值方法較規範方法計算結果更為閤理，為類似工程對管線影響評價提供瞭參攷。
성시내신건공정주변배경복잡，지하관선충류번다，재설계지초취수요고필시공이급공정영운대기안전적영향，단목전결핍통일적영향평개표준，수안조관선공능이급소속부문적상관규정작위기평개의거。해항목적관선위하천위언적2조직경위1.2 m、벽후위12 mm적배오관，채용FLAC3D건립료위언공정대대직경유압한접박벽배오관도적삼유수치계산모형，분4충불동시공공황진행료관도변형화응력계산。의거상관규범적요구，종관도본신적안전성화정상사용요구출발，병채용제4강도이론계산료상당응력，최대치위136.61 MPa，출현재최후추수공황하관1적외측。최대침강량39.3 mm대응적관체경사량위0.275%。장기결과여이론치진행대비，이론계산득도적상당응력최대치위188.18 MPa，고우수치계산결과，기원인위이론방법장각영향효응분별계산병진행간단상가。결과표명，의건위언공정대해관선적영향가공，수치방법교규범방법계산결과경위합리，위유사공정대관선영향평개제공료삼고。
There are a lot of kinds of underground pipes and structures in the urban area;the safety and regularly running of which must be taken into account during newly constructions. There are no generalized criterions to evaluate the safety and regularly running of them at present. It should be investigated which sectors the pipes belong to before construction, then their design and construction specifications can be used in the safety evaluation. Drainage design specifications are used to evaluate the safety of 2 large diameter steel sewage pipes with diameter of 1.2 m and thickness of 12 mm, during the cofferdam construction in the Litchi River in Guangzhou city. In view of the calculation methods in the design specification can not consider the interactions of all the effects during the construction. A three-dimensional simulation model of the whole cofferdam construction field stratum with the 2 large diameter steel sewage pipes is established. Deformation and stress of the pipes under 4 different construction conditions are calculated with FLAC3D. The equivalent stresses are calculated by fourth strength theory. The maximum value is 136.61 MPa, which appears at the outer surface of pipe No.1 under the last construction condition. The maximum settlement of the pipe is 39.3 mm, which produces 0.275% declination of the pipe. The maximum stress value calculated by theoretical calculation formulas is 188.18 MPa, which is much higher than the result calculated by the current codes. The reason is that every effort is calculated independently and simply added in the theoretical methods. Finally, Deformation and strength of the pipes are checked according to relevant Chinese standards. It reveals that the sewage pipe lines are safe in the construction procedure and the results got by numerical simulation are more reasonable than those calculated by theoretical formulas.
