交通科技
交通科技
교통과기
TRANSPORTATION SCIENCE & TECHNOLOGY
2014年
6期
119-122
,共4页
连续梁%收缩%徐变%规范比较%敏感性分析
連續樑%收縮%徐變%規範比較%敏感性分析
련속량%수축%서변%규범비교%민감성분석
continuous beam%shrinkage%creep%code comparation%sensitivity analysis
对《公路钢筋混凝土及预应力混凝土桥涵设计规范》（JTJ 023－85）和（JTGD62－2004）《铁路桥涵钢筋混凝土及预应力混凝土桥涵设计规范》99年版和2005年版、ASSHTO－1994规范中在相同条件下，通过不同的加载龄期、不同的环境相对湿度等其中一个参数变化时对各规范收缩应变、徐变系数进行分析和比较。主要结论为：混凝土收缩应变主要与环境的相对湿度有关；混凝土的徐变系数，各规范相差较大，铁路规范中徐变系数仅与加载龄期有关，与混凝土的所处相对湿度无关，且其徐变系数相差不大；公路规范中加载龄期及湿度均对其有影响，但湿度对混凝土徐变系数影响更为敏感；在设计和施工中尤其是混凝土前期养护时的湿度应重点关注。综合分析表明，JTGD62－2004考虑参数较多、较为合理，建议铁路规范进行适当调整。
對《公路鋼觔混凝土及預應力混凝土橋涵設計規範》（JTJ 023－85）和（JTGD62－2004）《鐵路橋涵鋼觔混凝土及預應力混凝土橋涵設計規範》99年版和2005年版、ASSHTO－1994規範中在相同條件下，通過不同的加載齡期、不同的環境相對濕度等其中一箇參數變化時對各規範收縮應變、徐變繫數進行分析和比較。主要結論為：混凝土收縮應變主要與環境的相對濕度有關；混凝土的徐變繫數，各規範相差較大，鐵路規範中徐變繫數僅與加載齡期有關，與混凝土的所處相對濕度無關，且其徐變繫數相差不大；公路規範中加載齡期及濕度均對其有影響，但濕度對混凝土徐變繫數影響更為敏感；在設計和施工中尤其是混凝土前期養護時的濕度應重點關註。綜閤分析錶明，JTGD62－2004攷慮參數較多、較為閤理，建議鐵路規範進行適噹調整。
대《공로강근혼응토급예응력혼응토교함설계규범》（JTJ 023－85）화（JTGD62－2004）《철로교함강근혼응토급예응력혼응토교함설계규범》99년판화2005년판、ASSHTO－1994규범중재상동조건하，통과불동적가재령기、불동적배경상대습도등기중일개삼수변화시대각규범수축응변、서변계수진행분석화비교。주요결론위：혼응토수축응변주요여배경적상대습도유관；혼응토적서변계수，각규범상차교대，철로규범중서변계수부여가재령기유관，여혼응토적소처상대습도무관，차기서변계수상차불대；공로규범중가재령기급습도균대기유영향，단습도대혼응토서변계수영향경위민감；재설계화시공중우기시혼응토전기양호시적습도응중점관주。종합분석표명，JTGD62－2004고필삼수교다、교위합리，건의철로규범진행괄당조정。
Taking one parameter variation between different loading time and different environmental relative humidity which are coming from reinforced and pre-stressed cement concrete design of high-way bridge (JTJ 023-85 )and (JTG D62-2004),pre-stressed and reinforced cement concrete design of railway bridge published in 1999 and 2005,AASHTO 1994 into consideration,shrinkage strain and creep coefficient of cement concrete according to different design specification are analyzed and com-pared.Some conclusions can be gained as follows:shrinkage strain of cement concrete is mainly asso-ciated with the relative humidity of environment;creep coefficient of cement concrete changes greatly according to different designing specification,creep coefficient of cement concrete which is only related to loading time and not relevant to relative humidity has a little change in railway specification;but creep coefficient is sensitive to humidity which is influenced by loading time and humidity in highway specification.So,humidity factor should be paid more attention for cement concrete maintenance dur-ing process of design and construction.The shrinkage strain and creep coefficient of cement concrete is comparatively reasonable in highway specification because more parameters are considered and there is a need of some appropriate adjustment in railway specification.
