CAJ | 학술논문

重大建设项目对施工过程中岩土体稳定性提出了更高的要求，常以一种动态设计施工模式来应对工程体的各类突发状况与病害。流变损伤模型既能反映岩土体在施工过程中变形的时效发展，又能反映其力学性质的时效劣化，继而能较准确地掌握工程体动态稳定性。基于以上考虑，为体现卸载边坡工程在卸载回弹阶段的瞬时塑性特征和时效演化阶段的黏塑性特征，因此，在流变模型中引入加载塑性元件和黏塑性元件，建立了复合黏弹塑（弹-黏-黏弹-黏塑-塑）模型，室内岩石压缩（卸载）蠕变试验证明了该流变模型的合理性，并对其参数进行辨识。在此基础上，从几何研究方法出发，引入反映节理分布的初始损伤张量及一种等效的依据黏塑性偏应变推导出的损伤演化方程，最终建立了一种新型的节理岩体等效流变损伤模型。将此模型用于川东红层某软硬岩互层型路堑边坡的卸载分析，结果表明：随不同的开挖阶段，易损部位（软岩集中段、软岩深埋段、软硬交接硬岩段）在瞬时卸载回弹阶段的塑性损伤和时效演化阶段的黏塑性损伤逐渐积累，边坡浅表部逐渐出现卸载损伤（松弛）带，在损伤累积中边坡各部位蠕变速率呈不同程度的增长。计算结果较好地反映了边坡变形、损伤发展与动态稳定性特征，其研究结果对于指导支护时机及相应的信息化施工具有一定的意义。
중대건설항목대시공과정중암토체은정성제출료경고적요구，상이일충동태설계시공모식래응대공정체적각류돌발상황여병해。류변손상모형기능반영암토체재시공과정중변형적시효발전，우능반영기역학성질적시효열화，계이능교준학지장악공정체동태은정성。기우이상고필，위체현사재변파공정재사재회탄계단적순시소성특정화시효연화계단적점소성특정，인차，재류변모형중인입가재소성원건화점소성원건，건립료복합점탄소（탄-점-점탄-점소-소）모형，실내암석압축（사재）연변시험증명료해류변모형적합이성，병대기삼수진행변식。재차기출상，종궤하연구방법출발，인입반영절리분포적초시손상장량급일충등효적의거점소성편응변추도출적손상연화방정，최종건립료일충신형적절리암체등효류변손상모형。장차모형용우천동홍층모연경암호층형로참변파적사재분석，결과표명：수불동적개알계단，역손부위（연암집중단、연암심매단、연경교접경암단）재순시사재회탄계단적소성손상화시효연화계단적점소성손상축점적루，변파천표부축점출현사재손상（송이）대，재손상루적중변파각부위연변속솔정불동정도적증장。계산결과교호지반영료변파변형、손상발전여동태은정성특정，기연구결과대우지도지호시궤급상응적신식화시공구유일정적의의。
Major engineering projects put forward higher requirements for rock stability in the process of construction, and a dynamic mode of engineering design is usually applied to deal with various kinds of emergencies and diseases. Rheological damage model can simulate both the time-dependent deformation of rock mass and the time-dependent degradation of mechanical properties, which can reflect the dynamic stability of engineering projects. In order to reflect the instantaneous plastic deformation in the unloading-rebound stage of slope as well as the viscoplastic deformation in the time-evolution stage of slope, loading-plastic and viscoplastic components are applied to the rheology model; thus a composite visco-elastoplastic model (elastic-viscous-viscoelastic-viscoplastic-plastic) is established. Results of compression(unloading) creep test proves the rationality of this model;and rheological parameters are recognized. On this basis, damage tensor describes the characteristics of joint geometry, and damage evolution equation based on the viscoplastic partial strain is established; eventually, a new type of equivalent rheological damage model of jointed rock is established. Applying this model to a soft-hard interbedded slope under the cutting(unloading) condition, the results show that instantaneous plastic damage in unloading-rebound stage and viscoplastic damage in time-evolution stage, of the damageable parts (soft rock section, buried section of soft rock, hard rock section of soft-hard handover), gradually accumulate;the unloading damage areas gradually appear;creep rates of every part gradually increase in varying degrees of growth with the damage accumulating. The reasonable analysis results can reflect the dynamic stability in the process of slope cutting, and guide the intervention time of supporting measures.