CAJ | 학술논문

随着近海工程向深水化、大型化发展，波浪循环荷载作用下软黏土地基弱化问题越来越受到关注。文章以烟台港原状淤泥质黏土为研究对象，通过动三轴试验，研究了不同围压、动应力和静偏应力影响下循环后不排水抗剪强度弱化规律和应力路径发展规律。在此基础上考虑实际工程中的土体状况，增加了固结度这一新的影响因素。试验结果表明存在固结度临界动应力比0.2，当动应力比小于等于0.2时，固结度对于土体强度弱化的影响基本一致；当动应力比大于0.2时，固结度对于强度弱化的影响突然加速。根据试验规律建立了综合考虑围压、动应力、静偏应力和固结度的多因素影响下不排水抗剪强度弱化公式，并采用拟静力方法将公式应用于烟台港防波堤数值模型的计算中，结果表明考虑强度弱化效应的计算方法更加接近工程实际。
수착근해공정향심수화、대형화발전，파랑순배하재작용하연점토지기약화문제월래월수도관주。문장이연태항원상어니질점토위연구대상，통과동삼축시험，연구료불동위압、동응력화정편응력영향하순배후불배수항전강도약화규률화응력로경발전규률。재차기출상고필실제공정중적토체상황，증가료고결도저일신적영향인소。시험결과표명존재고결도림계동응력비0.2，당동응력비소우등우0.2시，고결도대우토체강도약화적영향기본일치；당동응력비대우0.2시，고결도대우강도약화적영향돌연가속。근거시험규률건립료종합고필위압、동응력、정편응력화고결도적다인소영향하불배수항전강도약화공식，병채용의정력방법장공식응용우연태항방파제수치모형적계산중，결과표명고필강도약화효응적계산방법경가접근공정실제。
With the development of offshore engineering,strength reduction of soft clay foundation under cy?clic loading is attracting more attention. By means of performing cyclic triaxial test on muddy clay taken from Yan?tai littoral zone, undrained shear strength weakening and stress path of clay has been studied in different confining stress, deviator stress and dynamic stress. Given the actual soil condition in the engineering, the effect of consolida?tion degree has also been studied. Critical dynamic stress ratio has been found in the test. When the dynamic stress ratio is less than or equal to 0.2, strength reduction is affected by consolidation degree identically. On the contrary, when the dynamic stress ratio is greater than 0.2, consolidation degree has great influence on strength reduction. Ac?cording to the test, a strength weakening formula which contains different influencing factors was put forward. Then the formula was applied to the numerical model of breakwater in Yantai Port by using pseudo?static method. The re?sults show that the calculation method with strength weakening is more close to the engineering practice.