【摘要】：研究目的:坑中坑是工程中應(yīng)用較為普遍的一種非對(duì)稱基坑型式,目前相關(guān)的理論研究較少,工程設(shè)計(jì)中往往憑經(jīng)驗(yàn)確定其影響范圍。本文結(jié)合南京青奧軸線地下工程上部懸臂、下部設(shè)置內(nèi)支撐的基坑工程,通過有限元計(jì)算分析,探討坑中坑型式非對(duì)稱基坑圍護(hù)結(jié)構(gòu)的變形和土壓力分布特征,旨在為工程設(shè)計(jì)提供參考。研究結(jié)論:(1)內(nèi)、外坑圍護(hù)距離以及內(nèi)坑開挖深度對(duì)坑中坑圍護(hù)結(jié)構(gòu)變形和受力影響顯著;(2)隨著內(nèi)、外坑圍護(hù)距離的不斷縮小,內(nèi)坑圍護(hù)向坑外的變形不斷減小直至偏向坑內(nèi),內(nèi)坑圍護(hù)外側(cè)土壓力可按外坑為地表計(jì)算且考慮一定的安全系數(shù);(3)隨著內(nèi)坑開挖深度加大,內(nèi)坑圍護(hù)偏向基坑外側(cè)位移加大;內(nèi)坑未開挖或開挖較淺時(shí),坑底以上外坑圍護(hù)結(jié)構(gòu)側(cè)向土壓力介于主動(dòng)土壓力和靜止土壓力之間;內(nèi)坑開挖較深時(shí),坑底以上土壓力接近主動(dòng)土壓力,直至坑底逐步接近靜止土壓力;(4)本研究結(jié)果對(duì)類似基坑工程的分析與計(jì)算具有參考價(jià)值。
[Abstract]:Research purpose: the pit in the pit is a kind of asymmetric foundation pit which is widely used in engineering. At present, there are few related theoretical studies, and the influence range is often determined by experience in engineering design. In this paper, the deformation and earth pressure distribution characteristics of the pit type asymmetric foundation pit enclosure are discussed through finite element calculation and analysis, combined with the upper cantilever of the underground engineering of the Qingao axis in Nanjing and the foundation pit with inner support in the lower part. The aim is to provide reference for engineering design. The conclusions are as follows: (1) the distance of outer pit enclosure and the depth of pit excavation have significant effects on the deformation and force of the pit enclosure structure; (2) with the decrease of the distance between the outer pit and the inner pit, the deformation of the inner pit outside the pit decreases until it deviates to the pit. The external earth pressure of the inner pit enclosure can be calculated according to the outer pit surface and the safety factor can be considered to a certain extent. (3) with the increase of the excavation depth of the inner pit, the lateral displacement of the inner pit enclosure tends to increase, while the lateral earth pressure of the outer pit enclosure structure above the bottom of the pit is between the active earth pressure and the static earth pressure when the pit is not excavated or shallow; When the pit is deep, the earth pressure above the pit bottom is close to the active earth pressure until the bottom of the pit gradually approaches the static earth pressure. (4) the results of this study have reference value for the analysis and calculation of similar foundation pit engineering.
【作者單位】： 中鐵第四勘察設(shè)計(jì)院集團(tuán)有限公司;
【分類號(hào)】：TU753
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本文編號(hào)：2421554