2022年道路工程專業(yè)3000字外文翻譯

1、軟土路基解決措施概述摘要：軟土路基的加固有諸多種措施，本文對常用的幾種措施從加以解釋對其加固機(jī)理,作用,作用范疇以及個別的工程實例的論述.新型的加固材料以及新工藝的開發(fā)和運(yùn)用對提高軟土路基的加固技術(shù)水平所起的重要作用等做以簡樸的論述.在道路工程中常常會遇到軟土路基，由于高速公路、高速鐵路的發(fā)展，對地基的承載能力規(guī)定越來越高，天然的軟土地基遠(yuǎn)遠(yuǎn)不能滿足這些高檔次的構(gòu)造物對地基承載力的規(guī)定。20世紀(jì)8090年代，由于人口膨脹土地資源日益緊張，同步軟土路基加固的技術(shù)也有了長足的發(fā)展，經(jīng)濟(jì)條件有所改善，多種軟土加固理論得到了充足的應(yīng)用與驗證，軟基加固技術(shù)也得到長足發(fā)展，在不同的領(lǐng)域里均有涉獵；到20世

2、紀(jì)90年代后來,多種各樣的軟基解決技術(shù)已廣泛地應(yīng)用在多種道路工程中。地基中常用的軟土，一般是指處在軟朔或者流朔狀態(tài)下的粘性土。其特點是天然含水量大、孔隙比大、壓縮系數(shù)高、強(qiáng)度低，并具有蠕變性、觸變性等特殊的工程地質(zhì)性質(zhì)，工程地質(zhì)條件較差。選用軟土作為路基應(yīng)用，必須提出切實可行的技術(shù)措施。這種土質(zhì)如在施工中出目前路基填土或橋涵構(gòu)造物基本中，最佳含水量不易把握，很難達(dá)到規(guī)定的壓實度值，滿足不了相應(yīng)的密實度規(guī)定，在通車后，往往會發(fā)生路基失穩(wěn)或過量沉陷。其危害性顯而易見,故嚴(yán)禁采用。在軟土地基上修筑路堤，特別是橋頭引道，如不采用有效的加固措施，就會產(chǎn)生不同限度的坍滑或沉陷，導(dǎo)致公路破壞或不能正常使用即

3、所說的橋頭跳車。一般地，除要保證新填筑路基的密實度以減少沉降外，涉及原地面的地基總沉降必須達(dá)到基本穩(wěn)定，沉降量大體達(dá)到總沉降量的80%以上時，才容許鋪路面。軟土地基沉降嚴(yán)重時，不僅增長填方數(shù)量，并且沉降或水平位移對臨近填土的橋臺、擋土墻、涵洞，甚至對附近的住宅、農(nóng)田以及路線的技術(shù)原則都會產(chǎn)生很大的影響。為此，根據(jù)地基土的工程特性，選用合適的解決措施。通過長期的實踐，在公路、鐵路中形成了多種形式的軟土地基解決措施，結(jié)合諸多的施工公司近年施工經(jīng)驗及有關(guān)專家學(xué)者的論述進(jìn)行總結(jié)歸納如下：1 換填墊層法當(dāng)軟弱土層厚度不很大時，可將路基面如下解決范疇內(nèi)的軟弱土層部分或所有挖除，然后換填強(qiáng)度較大的土或其他穩(wěn)

4、定性能好、無侵蝕性的材料(一般是滲水性好的中粗砂)稱為換填或墊層法。此法解決的經(jīng)濟(jì)實用高度為23m，如果軟弱土層厚度過大，則采用換填法會增長棄方與取土方量而增大工程成本。通過換填具有較高抗剪強(qiáng)度的地基土，從而達(dá)到增強(qiáng)地基承載力的目的，滿足構(gòu)筑物對地基的規(guī)定。重要加固措施有換填、拋石擠淤、墊層、強(qiáng)夯擠淤幾種。墊層法根據(jù)材料的不同可分為砂(礫石)墊層、碎石墊層、粉煤灰墊層、干渣墊層、土(灰土、二灰)墊層。代表措施有砂墊層法及換填法。砂礫墊層：當(dāng)路堤高度不不小于極限高度的2倍，軟土層較薄，填筑材料比較困難，或雨季施工時，采用砂礫(砂)墊層，在填土與基底之間設(shè)一排水面，從而使地基在受到填土荷載后，迅速

5、地將地基土中的孔隙水排出，加快固結(jié)速度，提高地基的承載力，減少沉降，避免地基局部剪切變形。要注意控制填土速度，所用的材料為含泥量不不小于5%的干凈中粗砂，或最大粒徑不不小于5cm的天然級配砂礫。換填法：在軟土厚度不不小于2m 時，運(yùn)用滲水性材料(砂礫或碎石)進(jìn)行置換填土，可以減少壓縮性，提高承載力，提高抗剪強(qiáng)度，減少沉降量，改善動力特性，加速土層的排水固結(jié)。它的特點是施工工藝簡樸，但費用比較高。拋石擠淤：當(dāng)軟土或沼澤土位于水下，更換土施工困難，且厚度不不小于3m，表層無硬殼、基底含水量超過液限、路堤自重可以擠出的軟土之上，排水比較困難時，采用拋片石(直徑一般不不不小于 30cm)擠淤的措施。從

6、中部開始拋石，逐漸向兩邊延伸，擠出淤泥，提高路基強(qiáng)度。2 深層密實法采用爆破、夯擊、擠壓和振動及加入抗剪強(qiáng)度高的材料等措施，對地基深層的軟弱土體進(jìn)行振密和擠密的地基加固措施稱為深層密實法。合用于軟土厚度3m的中厚軟土的加固，分布面積廣的軟基加固解決，其加固深度可達(dá)到30m。通過振動、擠壓使地基中土體密實、固結(jié)，并運(yùn)用加入的具有高抗剪強(qiáng)度的樁體材料置換部分軟弱土體中的三相(氣相、液相與固相)部分，形成復(fù)合地基，達(dá)到提高抗剪強(qiáng)度的目的。重要加固措施：強(qiáng)夯法、土(或灰土、粉煤灰加石灰)樁法、砂樁法、爆破法、碎石樁法(振沖置換法)、石灰樁法、水泥粉煤灰碎石樁(CFG樁法)、粉噴樁法、旋噴樁法。代表措施

7、有碎石樁法、強(qiáng)夯法、水泥粉煤灰碎石樁法、粉噴樁法。 強(qiáng)夯法：對于砂土地基及含水量在一定范疇內(nèi)的軟弱粘性土地基，可采用重錘夯實或強(qiáng)夯。它的基本原理是：土層在巨大的沖擊能作用下，土中產(chǎn)生很大的壓力和沖擊波，致使土體局部壓縮，夯擊點周邊一定深度內(nèi)產(chǎn)生裂隙良好的排水通道，使土中的孔隙水(氣)順利排出，土體迅速固結(jié)。強(qiáng)夯后地基承載力可提高34倍，壓縮性可減少200%1000%。其佳夯擊能：從理論上講，在最佳夯擊能作用下，地基土中浮現(xiàn)的孔隙水壓力達(dá)到土的自重壓力，這樣的夯擊能稱最佳夯擊能。因此可根據(jù)孔隙水壓力的疊加值來擬定最佳夯擊能。在砂性土中，孔隙水壓力增長及消散過程僅為幾分鐘，因此孔隙水壓力不能隨夯擊

8、能增長而疊加，可根據(jù)最大孔隙水壓力增量與夯擊次數(shù)關(guān)系來擬定最佳夯擊能。蘭海高速公路某滑坡體的堆積破碎泥巖堆積物厚度412M.從土樣的土工實驗報告可知為低液限黏土含水量29.820.2,凝聚力13.812.2KPA,內(nèi)摩擦角13.820.2.擠密砂樁、碎石樁加固法：屬于復(fù)合地基的一種，當(dāng)軟土層較厚，換填解決比較困難，地基土屬于非飽和粘性土或砂土?xí)r，采用擠密砂樁或碎石樁加固法，可以使地基土密實，容重增長，孔隙比減少，避免砂土在地震或受震動時液化，提高地基土的抗剪強(qiáng)度和水平抵御力，減少固結(jié)沉降，使地基變均勻，起到置換、擠密、排水作用，避免地基產(chǎn)生滑動破壞，提前完畢沉降，減少沉降差。3排水固結(jié)法在軟土

9、地基上加壓并配合內(nèi)部排水，加速軟土地基的排水，加快軟土固結(jié)的解決措施稱為排水固結(jié)法。合用于解決各類淤泥、淤泥質(zhì)粘土及沖填等飽和粘性土地基。軟土地基在附加荷載的作用下，逐漸排出孔隙水，使孔隙比減小，產(chǎn)生固結(jié)變形。在這個過程中，隨著土體超靜孔隙水壓力的逐漸擴(kuò)散，土的有效應(yīng)力增長，并使沉降提前完畢或提高沉降速度。重要加固措施：堆載預(yù)壓法、砂井法、袋裝砂井、真空預(yù)壓法、電滲排水法、減少地下水位法、塑料排水板法。預(yù)壓解決：分為超載預(yù)壓、等載預(yù)壓和欠載預(yù)壓等，其施工工藝簡樸，但工期較長，超載預(yù)壓的時間一般為6個月，一般與排水解決地基相結(jié)合使用。廣州市新窯南路道路工程就是運(yùn)用堆載法加固軟土路基的.新窯南路道

10、路工程起點為廣州大道K4+600,終點為北山村K11+700,全長約7KM.道路沿線地層構(gòu)造自上而下分別為:地殼硬殼涉及松散狀雜填土,素填土和軟塑狀耕土,厚度為0.402.20;軟土層涉及流塑狀淤泥和淤泥質(zhì)土,厚度為1.519.39,沿線厚度變化大;下伏層涉及粘性土和砂層.堆載預(yù)壓時間從1995年到,大概78年.袋裝砂井：對于軟土厚度大、路堤穩(wěn)定、填土高的軟土路基，采用袋裝砂井，可增長軟土豎直方向的排水能力，縮短水平方向的排水距離，加速軟土的強(qiáng)度。砂袋灌入砂后，砂井可采用錘擊法或振動法施工。它的施工工藝復(fù)雜，費用相對較高，所用的時間較長，可采用矩形或梅花形布樁。珠江地區(qū)某市公路的地質(zhì)勘探表白，

11、地基土質(zhì)分布比較均勻，除表層1。0m左右耕植土外，接著為8.6m厚的高含水量、高壓縮性、低強(qiáng)度，高含粘性的超軟弱淤泥。第三層為厚約1.0m的貝殼粉砂土；第四層又為7.6m厚的淤泥質(zhì)粘土；如下分別是0.5m厚粘土和3.0m厚粉細(xì)砂。往下為擊數(shù)（SPT）不小于19擊的含礫粗砂層，再往下土質(zhì)更好。地基土質(zhì)為20m左右深厚的淤泥，含水量高達(dá)85.7%，十字板剪切強(qiáng)度僅4Kpa，且淤泥分布深度大體由前方向后方陸域傾斜，前淺后深，前方相對有利。在這樣大面積超軟弱的淤泥地基上筑路需作軟基深層解決，以避免施工期軟基沉降緩慢，引起工程竣工后仍有較大剩余沉降量，同步不致因加載引起地基失穩(wěn)破壞。這一帶因軟基不當(dāng)而浮

12、現(xiàn)工程質(zhì)量或安全事故是較常用的，就設(shè)計采用7cm袋裝砂井加砂墊層堆載預(yù)壓排水固結(jié)進(jìn)行軟基加固，目的是通過打設(shè)砂井使第二、四層淤泥土排水固結(jié)后，土質(zhì)強(qiáng)度獲得提高、減少工程投產(chǎn)后的沉降，保證工程的正常使用，滿足工程設(shè)計規(guī)定。塑料排水板：排水原理與袋裝砂井相似，由于是工廠制作，它的質(zhì)量穩(wěn)定、重量輕、運(yùn)送保管以便，施工工藝比較簡樸，投入勞力少，費用相對較低，并且滲濾吸水性好，具有一定的強(qiáng)度和延伸率，對土的擾動小，預(yù)壓時間較長，在工程中得到廣泛應(yīng)用，但對于提高土層的抗剪能力不如袋裝砂井。Overview of Soft Subgrade TreatmentAbstract: The reinforcem

13、ent of soft soil roadbed There are many ways, several to explain the reinforcement mechanism of the role, scope, and individual project example elaboration. New reinforcement materials and new technology development and utilization of soft subgrade reinforcement played an important role to do with t

14、he simple description. When road works are often encountered in soft soil subgrade, the carrying capacity of the foundation have become increasingly demanding due to the development of highway, railway, natural soft ground is far from meeting these high-grade structures are the foundation bearing fo

15、rce requirements. 1980s and 1990s, due to population expansion of land resources are becoming increasingly tense, soft soil subgrade reinforcement technology has made great progress, and economic conditions have improved, a variety of soft soil reinforcement theory has been fully Application and ver

16、ification of soft base reinforcement technology has made rapid progress in different areas are covered; to the 1990s, a variety of soft foundation treatment technology has been widely used in various road projects. Foundation in soft soil, usually in soft new moon or under the state of the flow of n

17、ew moon of the clay. Which is characterized by the natural water content, void ratio, compressibility factor, low strength and creep, thixotropy, and other special engineering geological properties, poor engineering geological conditions. Selection of soft soil roadbed application must be put forwar

18、d practical measures.Soil, such as in the construction of the base of the embankment or bridge and culvert structures, optimum moisture content is not easy to grasp, is extremely difficult to achieve the required degree of compaction can not meet the density requirements after the opening, often a r

19、oadbed instability or excessive settlement. Its obvious dangers, therefore prohibiting the use. Construction of embankment on soft ground, especially Bridge Approach, if not take effective measures for the reinforcement, it will have varying degrees of collapse slip or subsidence, resulting in road

20、damage or is not working is known as the Bump. In general, in addition to ensure that the new subgrade Using density to reduce the settlement In addition, the total settlements of the foundations of the original ground must meet the basic stability of the settlement roughly more than 80% of the tota

21、l settlement amount, to allow resurfacing. Serious settlement of soft ground, not only to increase the amount of fill, and subsidence or horizontal displacement of the bridge near the filling, retaining walls, culverts, and even the technical standards of the nearby residential, farmland, and the ro

22、ute will have a huge impact .To this end, according to the engineering properties of foundation soil, the selection of appropriate measures to deal with. After a long practice, the formation of roads, railways, various forms of soft ground, combined with a lot of construction companies many years of

23、 experience in construction and related experts and scholars discussed summarized as follows: 1 replacement cushion methodWhen the thickness of the soft soil, soft soil below the subgrade surface within part or all of the excavation, then change to fill the greater intensity of soil or other stabili

24、ty, non-erosive materials (usually good water permeability in coarse sand) called Replacement Cushioning. This economical and practical method to deal with the height of 2 to 3m, if the thickness of the soft soil is too large, then using the replacement method will increase the disposable side and d

25、ug side content and increase the cost of the project. Replacement higher shear strength of soil, so as to achieve the goal of enhanced foundation bearing capacity to meet the requirements of the structures on the foundation. Reinforcement Method Replacement, Stone Fill, cushion, COMPACTED silt sever

26、al. Cushioning according to the different materials can be divided into the sand (gravel) cushion, gravel pads, fly ash cushion, the cushion of dry residue, soil (dust, ash) cushion. Representatives of sand cushion method and replacement method. Gravel cushion: when the embankment height is less tha

27、n 2 times the limit height, soft soil layer is thin, the filling material is more difficult, or rainy season, construction, gravel (sand) cushion between the fill and the basement to set up a drainage face, so that the foundation by filling load in the foundation soil pore water discharge speed to a

28、ccelerate the consolidation to improve the bearing capacity of foundations, reduce sedimentation, to prevent the foundation of local shear deformation. Pay attention to controlling the filling speed, the materials used to clean coarse sand with mud is not more than 5%, or maximum particle size less

29、than 5cm natural gradation gravel. Replacement Method: water permeability material (gravel or crushed stone) in the soft soil thickness is not greater than 2m, filling replacement can reduce the compression to increase bearing capacity, shear strength, and reduce the settlement to improve the dynami

30、c characteristics accelerate soil consolidation by drainage. It is characterized by the construction process is simple, but the cost is relatively high. Stone Fill: When the soft soil or marsh soil located underwater, replace the soil construction difficulties, and the thickness is less than 3m, the

31、 surface without a hard shell, the substrate water content over liquid limit, embankment above the weight of the soft soil that can be squeezed out, drainage more difficult when using cast stone tablets (diameter generally less than 30cm) to squeeze the deposition method. Start from the middle of th

32、e rubble, gradually extending to the sides, out of mud, to improve the subgrade strength.2 deep compaction，The use of blasting, compacting, extrusion and vibration and join the high shear strength of materials, etc., the foundation of deep soft soil density vibration and compaction of the foundation

33、 reinforcement method is called deep compaction. For soft soil thickness 3m thick soft soil reinforcement, distribution of a wide area of soft Reinforcement processing, has consolidated its depth is up to 30m.Vibration, squeezing ground Turkey body dense consolidation, and added with high shear stre

34、ngth of the pile material replacement of part of the soft soil of the three-phase (gas, liquid and solid phase) portion to form a composite foundation, to improve the shear strength of purpose. Main reinforcement methods: dynamic compaction, soil (or dust, fly ash plus lime) piles, sand piles, blast

35、ing, gravel pile (vibration and substitution method), lime piles, cement, fly ash gravel pile pile (CFG), the DJM France, jet grouting piles. On behalf of rubble piles, dynamic compaction, cement and fly ash gravel piles, DJM France. The dynamic compaction method can be used to hammer compaction or

36、dynamic compaction: sand foundation and the water content in a range of soft clay foundation. Its basic principle is: the soil under the huge impact in the soil to produce a lot of pressure and shock wave, resulting in the soil of local compression, tamping points around within a certain depth to pr

37、oduce the fissures good drainage channel, so that the soil pore water (gas) discharged smoothly, the rapid consolidation of soil. Dynamic compaction, foundation bearing capacity can be increased 3-4 times, compression can be reduced from 200% to 1000%. Good ram is able to hit: In theory, the best ta

38、mping can function in the foundation soil pore water pressure reaches the soil weight pressure, such tamping energy known as the best tamping energy. Therefore, according to the superposition of the pore water pressure value to determine the best tamping energy. In sandy soil, the growth and dissipa

39、tion of pore water pressure of only a few minutes, the pore water pressure can not be with the tamping can increase and overlay, the maximum pore water pressure increment and the number of tamping relations to determine the best tamping can. Sea highway landslide accumulation of broken mudstone depo

40、sits thickness of 4 12M from the soil samples of the soil test report shows that for low liquid limit clay containing.Water 29.8 to 20.2, the cohesiveness 13.8 12.2KPA internal friction angle of 13.8 20.2. Sand compaction piles, rubble pile reinforcement method: a kind of composite foundation, thick

41、 soft soil replacement to handle the more difficult, the foundation soil is unsaturated cohesive soil or sand, sand compaction piles or broken Shizhuang reinforcement method, the foundation soil compacting bulk density increased, pores less than to prevent liquefaction of sand in the earthquake or b

42、y vibration and improve the foundation soil shear strength and the level of resistance, reducing the consolidation settlement, so that the foundation to change uniform , play replacement, compaction, drainage and to prevent the foundation to produce sliding failure, completed ahead of the settlement

43、 to reduce the differential settlement. 3 drainage consolidation method Pressure on the soft ground and in line with internal drainage, accelerate the drainage of the soft ground, speed up the processing of soft soil consolidation known as drainage consolidation method. For saturated cohesive soil f

44、oundation in handling all types of mud, silt clay and red fill.Soft ground in the role of the additional load is gradually passed to the pore water, the void ratio decreases, resulting in consolidation deformation. In this process, with the gradual diffusion of excess pore water pressure in soil, so

45、il effective stress, and settlement in advance or improve the settling velocity. Reinforcement methods: heap preloading method sand wells France, packed sand, vacuum preloading method, electro-osmosis water method, dewatering method, plastic drainage plate method. Preloading: divided into the surcha

46、rge preloading, set Preloading and less preloading, the construction process is simple, but a longer duration, surcharge preloading time is generally six months, usually used in conjunction with wastewater treatment foundation . New kiln South Road, Guangzhou City, road works is to use a heap load r

47、einforcement of soft soil roadbed. New kiln South Road road works starting point for Guangzhou Avenue K4, +600, and finish at North Village K11, to +700, total length of about 7KM road along the stratigraphic architecture were as follows: the crust hard shell loose, miscellaneous fill, fill factors,

48、 and soft plastic like cultivated soil, thickness of 0.40 to 2.20; soft layers including the flow of plastic-like silt and silty soil, thickness of 1.51 9.39, along thickness variation; underlying layer of cohesive soil and sand heap preloading time from 1995 to , about 7 to 8 years. Packed sand: so

49、ft soil subgrade for soft soil thickness, embankment stability, high filling, packed sand, increase the soft soil the vertical drainage capacity, shorten the horizontal direction of the drainage distance, accelerate the soft soil strength. Sand bags poured into the sand, sand wells can be used to hammering or vibration method of construction. Complexity of its construction process, the r