岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
3期
622-629
,共8页
陈建生%何海清%王霜%曾明明%王婷%何文政
陳建生%何海清%王霜%曾明明%王婷%何文政
진건생%하해청%왕상%증명명%왕정%하문정
无黏性土%管涌%黏土层%渗透系数%涌砂量%流量
無黏性土%管湧%黏土層%滲透繫數%湧砂量%流量
무점성토%관용%점토층%삼투계수%용사량%류량
cohesionless soils%piping%clay layer%coefficient of permeability%sand production%flux
管涌对堤防工程的危害极为严重,人类对管涌的认识也逐渐加深。目前,对管涌破坏开始的条件及其破坏后通道贯通的后果了解较多,然而,因其破坏及发展机制的复杂性,对于管涌发生后涌砂及流量的研究并不深入。通过自行设计的室内模型,改变上覆黏土的厚度对3组土性相同的无黏性土试样进行试验。对测压管水头、通道范围、涌砂量和流量等进行对比分析,研究孔隙率、渗透系数以及流量的变化规律,发现涌砂随时间变化满足非线性关系--Boltzmann模型。最后,利用渗透系数与孔隙率以及孔隙率与累计涌砂量的关系,推导并验证了流量随时间变化的理论公式。这对于认识管涌和有效控制管涌发展以及减灾避难有着非常重要的意义。
管湧對隄防工程的危害極為嚴重,人類對管湧的認識也逐漸加深。目前,對管湧破壞開始的條件及其破壞後通道貫通的後果瞭解較多,然而,因其破壞及髮展機製的複雜性,對于管湧髮生後湧砂及流量的研究併不深入。通過自行設計的室內模型,改變上覆黏土的厚度對3組土性相同的無黏性土試樣進行試驗。對測壓管水頭、通道範圍、湧砂量和流量等進行對比分析,研究孔隙率、滲透繫數以及流量的變化規律,髮現湧砂隨時間變化滿足非線性關繫--Boltzmann模型。最後,利用滲透繫數與孔隙率以及孔隙率與纍計湧砂量的關繫,推導併驗證瞭流量隨時間變化的理論公式。這對于認識管湧和有效控製管湧髮展以及減災避難有著非常重要的意義。
관용대제방공정적위해겁위엄중,인류대관용적인식야축점가심。목전,대관용파배개시적조건급기파배후통도관통적후과료해교다,연이,인기파배급발전궤제적복잡성,대우관용발생후용사급류량적연구병불심입。통과자행설계적실내모형,개변상복점토적후도대3조토성상동적무점성토시양진행시험。대측압관수두、통도범위、용사량화류량등진행대비분석,연구공극솔、삼투계수이급류량적변화규률,발현용사수시간변화만족비선성관계--Boltzmann모형。최후,이용삼투계수여공극솔이급공극솔여루계용사량적관계,추도병험증료류량수시간변화적이론공식。저대우인식관용화유효공제관용발전이급감재피난유착비상중요적의의。
Piping effect has serious hazards to river embankment engineering. The understanding of piping is gradually deeper and deeper to people. Nowadays, people know more about the beginning conditions of piping occurred and the consequences of piping channel completely penetrated the levee. However, because of the failure and development mechanism of piping is very complex, the study of the emission of sand and the flux after the piping effect is not deep enough. Three groups of cohesionless soils, in the same soil features, are used to make a series of tests by changing the thickness of overlying clay layer, using a self-designed equipment. A comparative analysis is made from the aspects such as piezometric head, scope of piping channel, sand production and flux. Furthermore the changing laws of the porosity, coefficient of permeability and flux are studied. It is found by the tests that cumulative amount of sand changing with time satisfies the Boltzmann model, a kind of nonlinear model. By using the relationship between permeability and porosity and the relationship between the porosity and cumulative amount of sand, a theoretical formula, from the changing flux over time, can be deduced and verified. The formula has a very important significance for the understanding of piping, the effective controlling of piping development, and the reducing or avoiding disasters of embankment collapsing.