重铺现有管道和涵洞正日益成为解决老化公共事业的流行方式。

• 最小中断流量
• 在许多情况下成本效益比置换
• 可能更快项目完成
• 较低的环境影响比置换

常规网格通常重125-135磅/立方尺。 轻量填充或低密度手机混凝土(LDCC)槽密度小至30pcf并常用约35-45pcf

In most reline applications, a new pipe is installed inside the existing line and the annulus between the two pipes is filled with grout.  The purpose of the grout is to fill the voids between the existing structure and the new reline pipe as well as to provide structural support for the new pipe.  The grout is typically delivered through a pumping operation.  Depending on the site conditions, the grout is either pumped through pipes of different lengths that are cast into a bulkhead at the ends of the reline pipe or it is pumped through grout ports that are installed throughout the length of the pipe being relined.  Regardless of how the grout is delivered, the mechanics of the filling of the void between the host and reline pipe are the same.  The grouting operation requires the grout to be fluid enough to flow around the annulus of the pipe and along the length of the pipe to fill the voids completely and provide uniform support for the reline pipe.  This assures positive transfer of loads from the host pipe to the reline after installation.

流式混凝土特征一般通过斜坡测试分类 。这涉及到用新混凝土填充集合维度并测量网格清除时水泥展品垂直运动量 。大多数中型可工作性混凝土和石料混合相向缩2至3.5级 。高可工作性混合通常显示斜坡4至5级

轻重水泥等轻点网格常有8到9分间滑动 。 这些材料可抽长距离并流到管道长度上更多距离 光重流中填充废品 。 轻重网格特性增加表示需要更少访问端口填充长线项目 。 此外,它提供更大的保证说明主机管道内外可能存在的任何空格都填充并连通管道有总和网格支持

轻量推理换行应用的另一个重要长处是,用浅推理反浮力需求下降,推理推理过程时重推线管道所传递的浮力。 任何推理过程都会产生易提升力(即推理推理推理过程)。float) the reline pipe until the grout can harden due to curing.  Floatation generally needs to be avoided to maintain the desired flowline elevation.  Therefore, countermeasures must be installed in order to resist the floatation forces.  These countermeasures can include strutting, blocking, spacers or other techniques to brace the pipe and keep it in place during the grouting operation.  The floatation force that has to be restrained is a combination of the grout lift heights used during installation and the density of the grout used to fill the annulus.  By using lighter weight grouts, the strutting required for the pipe can be reduced or the lift heights using during the grouting operation can be increased.  Larger lift heights can help accelerate the installation process.

Some engineers express concerns about the lower compressive strengths of the lightweight fills as compared to heavier, more conventional grouts.  While there is no question that the compressive strengths of lightweight fills is significantly lower than that of conventional grouts, for most applications the strength is still more than adequate to provide proper support and load transfer to the reline pipe.  Most conventional grouts have a compressive strength of 2,500 psi or greater.  Lightweight fill materials may have compressive strengths from 40 – 120 psi.  However, even 40 psi translates to 5,760 psf – which represents a support level similar to a compacted granular backfill.  That would be sufficient for the vast majority of culvert installations with low to moderate cover levels.  Very large structures or those with deep installations may require more strength, but the vast majority of installations would be fine from a strength perspective with the use of lightweight grout materials.

并带来各种优势-即考虑轻填充材料在更多线性应用中的使用时间