工程地质学报
工程地質學報
공정지질학보
2014年
5期
818-823
,共6页
王德银%唐朝生%李建%施斌
王德銀%唐朝生%李建%施斌
왕덕은%당조생%리건%시빈
贯入试验%结构强度%蒸发%含水率%干燥过程
貫入試驗%結構彊度%蒸髮%含水率%榦燥過程
관입시험%결구강도%증발%함수솔%간조과정
Penetration test%Structural strength%Evaporation%Water content%Drying process
研究土体结构强度对了解土体开裂破坏过程和预防相关工程地质问题有重要意义。以南京地区下蜀土为对象，采用超微型贯入试验方法，分析了试样在干燥过程中的结构强度演化特征。结果表明：所采用的超微型贯入试验方法为定量研究土体在干燥过程中结构强度的演化规律提供了可行的途径，该方法具有操作简单、精度高和含水率适应范围大等优点；在干燥过程中，当试样处于高含水率阶段时（w≥24.27％），剖面上的结构强度基本保持一致，空间差异性较小；在低含水率阶段（w＜24.27％），试样结构强度空间差异性显著增强，随深度的增加，结构强度呈递减趋势并逐渐趋于稳定；总体上，土体的结构强度在干燥过程中随平均含水率的减小呈指数递增趋势，这主要是由于土体水分蒸发导致吸力增加，土颗粒之间的作用力增强。此外，由于土体发生收缩变形，土体孔隙比减小，土颗粒间联接点增加，也会对结构强度产生贡献。
研究土體結構彊度對瞭解土體開裂破壞過程和預防相關工程地質問題有重要意義。以南京地區下蜀土為對象，採用超微型貫入試驗方法，分析瞭試樣在榦燥過程中的結構彊度縯化特徵。結果錶明：所採用的超微型貫入試驗方法為定量研究土體在榦燥過程中結構彊度的縯化規律提供瞭可行的途徑，該方法具有操作簡單、精度高和含水率適應範圍大等優點；在榦燥過程中，噹試樣處于高含水率階段時（w≥24.27％），剖麵上的結構彊度基本保持一緻，空間差異性較小；在低含水率階段（w＜24.27％），試樣結構彊度空間差異性顯著增彊，隨深度的增加，結構彊度呈遞減趨勢併逐漸趨于穩定；總體上，土體的結構彊度在榦燥過程中隨平均含水率的減小呈指數遞增趨勢，這主要是由于土體水分蒸髮導緻吸力增加，土顆粒之間的作用力增彊。此外，由于土體髮生收縮變形，土體孔隙比減小，土顆粒間聯接點增加，也會對結構彊度產生貢獻。
연구토체결구강도대료해토체개렬파배과정화예방상관공정지질문제유중요의의。이남경지구하촉토위대상，채용초미형관입시험방법，분석료시양재간조과정중적결구강도연화특정。결과표명：소채용적초미형관입시험방법위정량연구토체재간조과정중결구강도적연화규률제공료가행적도경，해방법구유조작간단、정도고화함수솔괄응범위대등우점；재간조과정중，당시양처우고함수솔계단시（w≥24.27％），부면상적결구강도기본보지일치，공간차이성교소；재저함수솔계단（w＜24.27％），시양결구강도공간차이성현저증강，수심도적증가，결구강도정체감추세병축점추우은정；총체상，토체적결구강도재간조과정중수평균함수솔적감소정지수체증추세，저주요시유우토체수분증발도치흡력증가，토과립지간적작용력증강。차외，유우토체발생수축변형，토체공극비감소，토과립간련접점증가，야회대결구강도산생공헌。
Study on the structural strength of soil is significant to the understanding of the soil cracking process and preventing related engineering geological problems.This paper takes the Xiashu soil in Nanjing as the object and uses the Super-Mini-Penetration (SMP )test.It analyzes the evolution characteristics of the structural strength of specimens during the drying process.The results show that the SMP test method is a better way for the quantitative study of structural strength of soil during the drying process.This method has the advantages of simple operation, high precision and a wide range of moisture content.During the drying process,the structural strength of specimen section remains stable and its spatial difference is very small in the high moisture content range(w≥24.27%).In the relative low water content range (w<24.27%),the spatial difference of soil structural strength become more evident.As the penetration depth increase,the structural strength decreases and gradually become stable.The soil penetration stress increases exponentially as the average moisture content decreases,which is mainly due to the increase of soil suction caused by the soil water evaporation and the enhancement of interaction force among soil particles.In addition,the decrease of pore ratio and the increase of the soil particle joint point due to the shrinkage deformation of soil will also contribute to enhance the structural strength of clayey soil.
