Question:
Bored Piles in Runyang Yangtze River Highway Bridge stent based on the successful application processing
Answer:
Bored Piles in Runyang Yangtze River Highway Bridge stent based on the success of treatment 1.1 an overview of the use of an engineering project Runyang Yangtze River Highway Bridge H2 S (Yuejin Road Interchange) project area is located in Zhenjiang City润州five ferry town of Jiang Qiao Village, sharing the main line of northbound access Runyang Yangtze River Highway Bridge South Approach. Yuejin Road Interchange 8 in conjunction the main line of the bridge, long bridge design 1392.44m, the cross-hole span for a single 43.4-48m range, the upper structure of prestressed concrete continuous box girder, single-or dual-chamber box, Room structure, each bridge high beam bridge centerline 2.8m, box-girder bridge to the bottom level, cross-slope from the formation of non-high box rib, the lower part of the use of thin-walled bridge piers, dumbbell-shaped cross-section, the maximum pier height of 41m. Yuejin Road exchange set up A, B, C, D, E ramp bridge and the bridge connecting the main line, main line of changing the width of the bridge box girder, the use of sliding-mode method can not only support use of hole-by-construction method. 1.2 exchange of hydrogeological conditions project area is located in the alluvial plain of the Yangtze River flood plain areas of engineering geology, surveys revealed that the exchange zone for the upper layers of the Yangtze River floodplain sediment layer red, muddy soil as the gray sub-clay, silty clay Asia through crystals, soft - plastic flow state, in - the high-compression, thick slice; middle layer for the Pleistocene clay sallow, sub-clay, hard - plastic state, in the - low-compression. Types of groundwater exchange zone pore water and fissure water two major endowed with the pore water in the Yangtze River alluvial floodplain, surface diving and is closely linked to the Yangtze River water, shallow depth. About 1.3 stent construction program Runyang Yangtze River Highway Bridge S H2 exchange Yuejin Road, the main line of cast-in-place box girder bridges are used less stent buttress construction method-by-hole construction. Divided into small buttress support beam, beams, steel pipes, such as the main part of the support. Detailed structure shown in figure 1. Box on the map by the known stent longitudinal bridge support to set up five-row, in which two rows of piers on pier was located in the bearing bracket to the middle three rows of steel box girder construction support will be conveyed to the foundation load, so, how to choose a stent based on the quality of the construction of the box, security, economic is vital. 2 stent treatment options based on 2.1 and comparison of stent loading and geological conditions in accordance with the results of structural calculations of the upper box, the basis of the load for the following: while the fulcrum of the basis of the carrying capacity of ≥ 850KN fulcrum ≥ 1850KN the basis of the carrying capacity of the district according to the hydrogeological conditions of exchange, if the basis of the traditional programs to expand capacity and unable to meet settlement requirements, can only be considered to deal with pile foundation program. 2.2 Comparison and Selection of a program selection table, according to a comprehensive comparison table drawn: Bored Piles processing the case as the basis in the construction are widely used in construction, technology mature and less environmental pollution, the construction cycle, fast, good economic indicators can be used as the basis for dealing with the main line of the bridge support the program of choice. Comparison of sub-items into the immersed tube of precast piles bored pile foundation technology that will have a pre-set at the bottom tip of the steel pipe pile hammering or vibration sink to the design requirements for steel pipe buried in the depth of placement in the cage of reinforced concrete and reperfusion, in the vibration extubation into piles at the same time. Pile hammer on the impact energy will pile into the earth. Drilling holes into the use of the roundabout, under the cage of reinforced concrete pile reperfusion. Advantage of the construction site at any time can be adjusted according to length, process maturity, less environmental pollution. Can be factory-produced, high reliability and good reliability can be immersed tube as a result of the shortcomings of the role of the extrusion, in the soft clay, or soft and hard layer at the junction of necking easily. Pile length to be determined in advance, to be the carrying capacity of the foundation construction noise. High load-bearing capacity of foundation, pile the end of the second to be carried out on-site clean-up. Preliminary design (in the first hole of the first pivot joint as an example) using 5 φ4 Address: interactive real estate information network resources2008-04-30
问题:
沉管灌注桩在润扬长江公路大桥支架基础处理中的成功运用
回答:
沉管灌注桩在润扬长江公路大桥支架基础处理中的成功运用 1 工程概述 1.1工程简介 润扬长江公路大桥H2标（跃进路互通）工程位于镇江市润州区蒋乔镇五摆渡村，互通主线桥北接润扬长江公路大桥南引桥。 跃进路互通立交主线桥共8联，设计桥长1392.44m，各孔单跨跨径为43.4—48m不等，上部结构为预应力混凝土连续箱梁，单箱双室或三室结构，每幅桥桥梁中心线梁高2.8m，箱梁横桥向底板水平，横坡由不等高箱肋形成，下部采用薄壁桥墩，哑铃型断面，{zg}墩身高度为41m。 跃进路互通设置A、B、C、D、E匝道桥与主线桥相连接，主线桥箱梁宽度不断变化，无法采用滑模法施工，只能采用有支架逐孔施工方法。 1.2 工程水文地质条件 互通区位于长江漫滩冲积平原工程地质区，勘察揭示，互通区上部土层为长江漫滩相冲淤积层，土性为灰色淤泥质亚粘土、亚粘土粉砂透晶体，软—流塑状态，中—高压缩性，层厚较厚；中层土层为上更新统灰黄色粘土、亚粘土，硬—可塑状态，中—低压缩性。互通区地下水类型有孔隙水和裂隙水两种，孔隙水主要赋有于长江漫滩冲积层，表层潜水与长江水联系密切，埋深较浅。 1.3支架施工方案简介 润扬长江公路大桥跃进路互通H2标主线桥现浇箱梁采用少支墩有支架的逐孔施工方法施工。少支墩支架分为纵梁、横梁、钢管支撑等几个主要部分。详细结构见图1。 由上图知箱梁支架纵桥向设五排支撑，其中靠桥墩两排通过在墩身上设牛腿来承载，中间三排钢管支撑将箱梁施工荷载传到地基上，因此，如何选择支架基础对整个箱梁施工的质量、安全、经济都是至关重要的。 2 支架基础处理方案选择与比较 2.1 支架荷载及地质状况 根据箱梁上部结构计算结果，基础所承 荷载如下： 边支点基础承载能力≥850KN 中支点基础承载能力≥1850KN 根据互通区水文地质条件，若采用传统扩大基础方案无法满足承载力及沉降要求，只能考虑采用桩基础处理方案。 2.2 方案比选 方案比选见表一，根据表中综合比较得出：沉管灌注桩作为基础处理案在建筑施工中被广泛采用，工艺成熟，对环境污染少，施工周期快，经济指标良好，可作为主线桥支架基础处理的{sx}方案。 分项比较 沉管灌注桩 预制打入桩基础 钻孔灌注桩 工艺说明 将底部套有预制桩尖的钢管锤击或振动下沉到设计要求入土深度后在钢管内安放钢筋笼灌注砼，在振动的同时拔管成桩。 靠桩锤的冲击能量将桩打入土中。 利用回旋钻机成孔，下设钢筋笼灌注砼成桩。 优点 可根据现场施工随时调整桩长，工艺成熟，环境污染少。 可工厂化制作，可靠性高 可靠性能好 缺点 由于沉管的挤压作用，在软粘土或软、硬土层交界处易产生缩颈。 桩长需事先确定，施工地基需承载能力噪音大。 地基基础承载能力高，桩基结束需对现场进行二次清理。 初步设计（以{dy}联{dy}孔中支点为例） 采用5根φ4 地址：地产互动资源信息网2008-04-30