[4] Zuanfeng Pan *, Zhitao Lüand Chung C. Fu
Experimental Study on Creep and Shrinkage of High-Strength Plain Concrete and Reinforced Concrete
Abstract: It is important to accurately estimate creep and shrinkage effects in long-
span continuous box girder bridges. Based on the experiments on creep and shrinkage
of the plain concrete used in the continuous rigid frame of Sutong Bridge, China, the applicability of ACI 209-82, JTG D62-2004, B3 and GL2000 prediction model for
creep and shrinkage on the high-strength concrete is evaluated. Also, a modified
model based upon JTG D62-2004 is presented. Results indicate that the accuracy of
prediction of creep and shrinkage can be enhanced greatly by carrying out short-term
creep and shrinkage measurements on the given concrete and modifying the prediction
model parameters accordingly. Furthermore, the presence of steels can have an impact
on the time-dependent deformations caused by creep and shrinkage, accordingly,
the restraint influence of steels on creep and shrinkage is investigated through the
reinforced specimens with different reinforcement ratio. Formulas of influence
coefficients of steels on creep and shrinkage are derived, and a good agreement is
observed between the calculated values of the influence coefficients of steels on creep
and shrinkage and the measured data in each specimen. The reinforced specimens can
be also used for calibrating the modified model.
摘要：对于大跨度连续箱梁桥重要的是要准确地估计在长期蠕变和收缩的影响。在普通混凝土中基于蠕变和收缩的实验用于中国苏通大桥，中苏通大桥连续刚构使用的适用于ACI 209-82 ，JTG D62 -2004 ，B3和GL2000被评为蠕变性和高强度混凝土的收缩预测模型。此外，修改后的基于JTG D62 - 2004模型出现了。结果表明，通过开展短期预测，可以大大提高蠕变和收缩在给定的具体测量和修改预测的相应的模型参数的测量精度。此外，钢材的存在可以产生影响由收缩和徐变引起的随时间变化的变形，钢材对混凝土徐变和收缩的一直作用通过不同配筋率的钢筋样本调查得到。钢材对徐变和收缩的影响系数可用公式表示，并且由公式得出的钢材对徐变和收缩的影响系数计算值和通过每个试样测得的影响系数符合得很好。钢筋标本也可用于校准修正模型。
[5]Xianmin Li Mengshu Wang Yanhui Liang
Research into Design and Construction Key Technologies of Prestressed Concrete Continuous Rigid Frame Bridge
Abstract—Fengshi River especially big bridge, “The first highest bridge in Zhongyuan”, is the largest large-span concrete continuous rigid frame bridge in Henan express way. The superstructure of main span is the pre-stressed concrete continual rigid frame, and the substructure is rectangle hollow thin wall pier, and the highest pier is 107 meters high and with 2.2 meter width pile group foundation; the self-lifting platform
trap door method of construction is adopte d to construct high pier, and the two “T” synchronous suspending crane construction method, cantilever concreting method, is adopted to construct box girder; for achieving the goal of making formed bridge state of constructing be consistent as the designed bridge state, of making the stress state be reasonable of making the line of formed bridge be smooth, the field construction quality
implementation group is established, and it implements the entire process quality safety control and the technical guarantee such key links as safety, material quality and so on; Thus speed up the construction progress and guaranteed the project quality and the construction security, and accumulated much important project experience for the concrete continual rigid frame bridge structural design and the construction quality control.
摘要冯氏河特大桥，“中原第一高桥，在河南高速公路上，是中原最大的大跨度混凝土连续刚构桥。“上层建筑是主跨预应力混凝土连续刚构，下部结构为矩形空心薄壁墩，最高墩高107米和宽2.2米的群桩基础;高墩采用自升降平台陷阱门施工方法，箱梁是通过构建高两个的“T ”同步悬挂起重机施工方法和悬臂浇筑施工方法，为实现成桥状态与设计的桥梁状态一致，应力状态合理和成桥线形顺利，成立了现场施工质量实施小组，它实现了全过程质量安全控制和技术保障。因此，如何保证关键环节施工安全和材料质量安全等，从而加快施工进度，保证工程质量安全，并积累了非常重要的混凝土连续刚构桥的结构设计和施工质量控制的项目经验。
[6] Wang Guanghui Wei Chenglong Liu Xiaoyan
Research On Key Question Of Joint Of Large Span Pre-Stressed
Box-Girder Concrete Continuous Rigid Frame Bridge With High Piers
ABSTRACT In the construction of a Large Span Pre-stressed Box-girder Concrete Continuous Rigid Frame Bridge with High Piers, the joint plan of the bridge depends
on the construction conditions and design status. In this study, several joint plans
were analyzed using the nonlinear finite element method for finding an optimum
joint plan. In the analysis, the space beam elements were used to simulate the piles,
the piers and the beams, and the link element to simulate pre-stressed reinforcement.
The technology of element life and death was used to simulate the construction
process. The non-line effects associated with big distortion, concrete shrinkage, and
creep were considered in the simulation. Aiming at the high temperature joint of the
bridge, a new technique, namely ‘loading anti-jacking force’, was proposed based on
the analysis of the impaction related to the high temperature joint of the structure. In addition, the formula of the anti-jacking force was given originally. This research demonstrated that the non-linear finite element method is effective in engineering
practice. This research can provide references for the design, the construction, and
the monitoring of similar bridges.
