铁道标准设计
鐵道標準設計
철도표준설계
RAILWAY STANDARD DESIGN
2015年
7期
23-27
,共5页
铁路路基%膨胀土%填料%改良试验
鐵路路基%膨脹土%填料%改良試驗
철로로기%팽창토%전료%개량시험
Railway subgrade%Expansive soil%Filler%Improvement test
拟建阳安二线沿线膨胀土广泛分布，膨胀土不能直接作为路基填料，如果选取合格填料，运距较远、投资大，而且挖方地段的膨胀土又得弃掉、占地多，极不经济。通过选取现场两处代表性取土场取样，生石灰粉作添加剂，按4%、6%、8%、10%四个级别的掺入比做室内改良试验，试验表明：生石灰掺入比大于4%改良后，能达到消除膨胀性的目的，改良土有较好的水稳性和较高的强度，能满足设计要求；改良土较原膨胀土有较高的抗压强度和剪切强度，且随生石灰的掺入比增加而增大；得出了路基不同部位、不同膨胀级别膨胀土的生石灰粉掺入比，为阳安二线路基填料设计提供了理论依据。
擬建暘安二線沿線膨脹土廣汎分佈，膨脹土不能直接作為路基填料，如果選取閤格填料，運距較遠、投資大，而且挖方地段的膨脹土又得棄掉、佔地多，極不經濟。通過選取現場兩處代錶性取土場取樣，生石灰粉作添加劑，按4%、6%、8%、10%四箇級彆的摻入比做室內改良試驗，試驗錶明：生石灰摻入比大于4%改良後，能達到消除膨脹性的目的，改良土有較好的水穩性和較高的彊度，能滿足設計要求；改良土較原膨脹土有較高的抗壓彊度和剪切彊度，且隨生石灰的摻入比增加而增大；得齣瞭路基不同部位、不同膨脹級彆膨脹土的生石灰粉摻入比，為暘安二線路基填料設計提供瞭理論依據。
의건양안이선연선팽창토엄범분포，팽창토불능직접작위로기전료，여과선취합격전료，운거교원、투자대，이차알방지단적팽창토우득기도、점지다，겁불경제。통과선취현장량처대표성취토장취양，생석회분작첨가제，안4%、6%、8%、10%사개급별적참입비주실내개량시험，시험표명：생석회참입비대우4%개량후，능체도소제팽창성적목적，개량토유교호적수은성화교고적강도，능만족설계요구；개량토교원팽창토유교고적항압강도화전절강도，차수생석회적참입비증가이증대；득출료로기불동부위、불동팽창급별팽창토적생석회분참입비，위양안이선로기전료설계제공료이론의거。
The expansive soil is widely distributed in the proposed YangAn second line and the expansive soil can not be directly used as roadbed filler. If other qualified filling material is used the haul distance will be longer with heavy investment, waste of excavated expansive soil and more land coverage. A test is conducted with two representative field soil samples and lime powder as additive in 4%, 6%, 8% and 10% of four levels of incorporation for improvement. Test results show that the soil improvement with mixing ratio greater than 4% can eliminate the swelling, and the improved soil has good water stability and higher strength and meets the design requirements. Compared with the original expansive soil, the improved soil has higher compressive strength and shear strength with the increase of the lime mixing ratio. The mixing ratios for different part of subgrade and different grade of expansive soil are obtained, providing theoretical reference for the design of YangAn second-line subgrade filler.
