土工编织袋防护膨胀土路堑边坡的应用研究

Design method of soilbags for protecting cutting slopes of expansive soils

膨胀土滑坡和工程边坡失稳滑坡以浅层胀缩裂隙控制的滑坡为主,分隔技术就是将引起坡体水分变化的外界因素与坡体分隔开来,有效地阻止胀缩裂隙发育,增加膨胀土边坡的稳定性。土工编织袋能有效地阻止水分变化,是典型的分隔技术。土工编织袋分隔技术起到分隔水分变化因素、反压护坡抑制膨胀变形、增强坡体的作用。提出考虑膨胀力的膨胀土朗肯土压力理论,建立土工编织袋防护膨胀土边坡的设计方法;依托广西崇(左)-爱(店)高速公路膨胀土路堑边坡防护的应用示范工程,构造膨胀土边坡防护的土工编织袋组合单元,提出膨胀土边坡防护的土工编织袋方法;根据膨胀土路堑边坡防护工程中土工编织袋的破坏案例,解析土工编织袋的破坏形式。

The failures and slides of slopes of expansive soils are usually characterized by shallow sliding due to the fissures in the slope surface.The separation technology is to separate the external factors that cause their water change from the slopes,effectively prevent the fissure development induced by swelling and shrinkage,and thus effectively guarantee the stability of the slopes expansive soils.The soilbag protection technology is the typical separation method for the slopes of expansive soils,because the soilbage can effectively prevent moisture change from the slope surface.As a separation technology,the soilbag plays a role in separating the moisture change factors,restraining the swelling and strengthening the slope surface.The Rankine’s earth pressure theory of expansive soils is presented according to the effects of swelling pressure.The design method of soilbags to protect slope failures of expansive soils is proposed for the protection of the slopes of expansive soils.The basic heap-up units of soilbags are constructed based on the application of soilbags to the cutting slope pretection of expansive soils in Chongzuo-Aidian highway of Guangxi Province.Therefore,the design method of soilbags to protect the slopes of expansive soils is proposed and standardized.