检查井通病原因分析

Analysis of causes of common faults in inspection wells

1.1施工工艺所致

1.1 the result of construction process

施工工艺是检查井质量控制消除病害的关键环节，施工质量的优劣直接影响着检查井的使用效果。其原因主要存在以下三个方面

The construction technology is the key link to control the quality of the inspection well and eliminate the disease. The quality of the construction directly affects the use effect of the inspection well. The main reasons are the following three aspects

(1) 检查井地基承载力不够。路面上的重力动荷载是通过检查井的井盖传至检查井井体，再通过井体垂直作用于地基上，即路面检查井上的车荷载最终是作用在检查井地基上的。这就要求检查井地基的承载力必须达到一定的强度，否则在上部长时间动荷载的作用下 ，地基土就会被压缩下沉，致使检查井整体下沉 ，检查井出现凹陷，路面不平整

(1) the bearing capacity of the inspection well foundation is not enough. The gravity dynamic load on the pavement is passed through the cover of the well to check the well body, then the vertical action of the well body on the foundation, that is, the vehicle load on the pavement inspection well is ultimately on the inspection of the well foundation. This requires that the bearing capacity of the foundation of the inspection well must reach a certain strength, otherwise the foundation soil will be compressed and sink under the action of the long time moving load on the upper part, resulting in the overall sinking of the inspection well, the inspection well and the unevenness of the pavement.

(2) 压实度不达标。路面结构与检查井的刚度相差大，存在刚性与柔性转换问题。保证井周回填土压实度至关重要。根据《给水排水工程构筑物施工及验收规范》(G B5014 1—2008) ，检查井周围回填土的压实度应当与道路基层压实度相同，即压实度应大于等于 95 ％(重型压实标准 )，但在井施工过程中普遍做法是在井筒砌筑完成后，井与工作坑之间距离狭小，导致机械碾压困难 ，一般绕

(2) the degree of compaction is not up to standard. There is a big difference between the stiffness of the pavement structure and the inspection shaft, and there is a problem of rigidity and flexibility conversion. It is very important to ensure the compaction degree of the backfill soil. According to the code for construction and acceptance of water supply and drainage engineering structures (G B5014 1 - 2008), the compaction degree of backfill surrounding the well should be the same as that of the road base, that is, the compaction degree should be equal to 95% (heavy compaction standard), but the common practice in the well construction process is the well and the working pit after the wellbore is built. The distance between them is narrow, resulting in difficulty in mechanical rolling and general winding.

过井一定距离碾压；而人工夯实又难 以控制质量，从而导致井周回填土在使用过程中逐渐沉降，引起井周路面下沉，检查井四周开裂。

It is difficult to control the ramming of the cross well, and it is difficult to control the quality by artificial tamping, which leads to the gradual settlement of the backfill soil during the use of the well, causing the sinking of the circumferential pavement and checking the cracks around the well.

(3) 施工时高程控制不严格及施工工期的压缩。很多施工单位都是在道路侧石砌筑完成后，参照侧石的标高确定井盖的标高。忽略了道路的横向坡度，使井盖标高和道路设计标高不协调，检查井盖高出或低于路面，在使用过程中受到车辆荷载冲击作用后会加剧井盖与井周路面的不均匀沉降

(3) the height control is not strict during construction and the construction period is compressed. Many construction units determine the elevation of the well cover according to the elevation of the side stone after the completion of the side stone masonry. The lateral slope of the road is ignored, which makes the height of the shaft cap uncoordinated with the road design elevation, and the cover of the well is higher or lower than the road surface. The uneven settlement of the shaft cover and the well surface will be aggravated by the impact of the vehicle load during the use process.

(4) 市政道路行业的施工工期压缩也是造成检查井病害的一

(4) construction period compression of municipal road industry is also one of the diseases causing inspection wells.

个不容忽视的原因。混凝土达到设计强度所需时间都在 28d 以上，若工期安排不合理，在混凝土强度还未形成前就进行碾压，极易造成施工期间的破坏；另一方面养护时间达不到要求，施工单位为避免重夯造成井身变形 ，不敢对井周回填土进行较强夯实。

A reason that can not be ignored. The time required for the concrete to achieve the design strength is more than 28d. If the schedule is not reasonable and the concrete strength has not been formed before the concrete strength is formed, it is very easy to cause damage during the construction period; on the other hand, the maintenance time can not reach the requirement. The construction unit can avoid the shape of the well body to avoid the heavy ramming, and dare not to carry on the comparison of the backfill soil in the well. Strong tamping.

1.2检查井支座松动，井周路面沥青面层开裂。新晋祠路开井后发现，多数该类检查井井筒完好，井盖和支座均出现了松动，支座下的座浆和井内抹面出现不同程度的脱落。

1.2 the bearing of the inspection well is loose, and the asphalt pavement surface cracks on the well side. After the opening of the new Jinci Road, it is found that most of this kind of inspection well bore is intact, the cover and support of the well have been loosened, and the slurry and the hole surface under the support have different degrees of falling off.

2. 检查井通病解决方案

2. solution of common fault in inspection well

2.1基础施工

2.1 basic construction

检查井的地基必须符合设计或施工规范要求，在天然地基上施工时不得扰动原状土，在软弱地基上施工时必须先进行处理，使地基达到设计承载力，以保证检查井施工的质量。待地基整平压实后，先浇筑素混凝土底板，其强度等级不应小于C15，厚度不小于15cm ，宽度大于井身 10cm以上为宜，而后方可进行井身施工。在检查井地基整平压实及混凝土底板浇筑过程中，严禁带水作业，若在雨季等雨水不可避免的条件下施工时应在基础以外设置排水沟及集水井，及时排水，保证施工质量。

The foundation of the inspection well must conform to the requirements of the design or construction specification. The original soil should not be disturbed during the construction of the natural foundation. It must be treated first in the construction of soft ground so that the foundation can reach the design bearing capacity so as to ensure the quality of the construction of the inspection well. After the foundation is leveled and compacted, the plain concrete floor is poured first, its strength grade should not be less than C15, the thickness is not less than 15cm, the width is more than 10cm above the shaft, and then the well body construction can be carried out. In the process of inspection and compaction of the foundation of the well and the pouring of the concrete floor, it is strictly forbidden to carry water operation. If the rain season and other rainwater are unavoidable, the drainage ditch and the water collecting well should be set outside the foundation to ensure the quality of the construction in time.

2.2检查井井身施工

2.2 inspection well body construction

若条件允许，应优先考虑采用预制混凝土检查井，其能有效减少施工周期，并提供高强度的井身结构，施工时随路基的填筑不断加高直至设计高程；若采用砖砌工艺，砌筑前先将砖充分润湿，砂浆标号不低于M7.5，每层砖的砌筑砂浆应填充饱满，检查井高度以道路基层底部高程为准。若检查井有管道接入，在管道与井身连接处必须将缝隙填充严密，防止漏水、渗水，对于直径大于300mm 的管道，须在接口外砌筑砖圈加固，防止渗水。检查井内外壁必须在填筑路基前粉刷1：2防水水泥砂浆，厚度不得小于2cm ，对于接缝、管口等位置需要重点处理。严禁先施工管道后砌筑检查井或者先施工检查井再浇筑混凝土底板。

If the conditions permit, the prefabricated concrete inspection well should be given priority, which can effectively reduce the construction period and provide high strength wellbore structure, with the filling of the subgrade up to the design elevation in the construction. If the brick process is used, the bricks are fully wetted before the masonry, and the mark of the sand slurry is not less than M7.5, and the masonry of each layer of brick is built. The mortar should be filled with full height and the height of the inspection well shall be based on the bottom elevation of the road base. If the inspection well has pipeline access, it is necessary to fill the gap between the pipe and the shaft to prevent leakage and seepage. For the pipe with a diameter greater than 300mm, the brick ring must be reinforced outside the interface to prevent water seepage. The inside and outside walls of the inspection well must be painted with 1:2 waterproof cement mortar before filling the foundation. The thickness should not be less than 2cm. It is strictly prohibited to construct the inspection well after construction of the pipeline, or to construct the inspection well before pouring the concrete floor.

2.3检查井周边路基回填和压实

2.3 the backfill and compaction of the subgrade surrounding the inspection well

对于检查井周边，选择合适的回填材料和压实方法是关键。当每层路基填筑压实后，由检查井周边向外反挖50cm ，然后采用粗砂、或直径不大于3厘米的碎石回填并立式冲击夯压实，压实度不小于95%。

For the periphery of the inspection well, the right backfill material and compaction method are the key. When the subgrade is filled and compacted each layer, the 50cm is dug from the periphery of the inspection well, and then the coarse sand, or the crushed stone which is not more than 3 cm in diameter, is filled and compacted with vertical impact ramming, and the degree of compaction is not less than 95%.

2.4检查井井圈施工

2.4 inspection well ring construction

为了使检查井井盖和井身能够很好的连接共同受力，在井身顶部设置井圈，采用C50钢纤维速凝混凝土浇筑。井圈标高一般与水泥稳定层相同即可。施工时在井口安放一块直径稍大的厚钢板（或其他承重物）盖住井口，当做临时井盖，并做好标记，与水泥稳定层一并摊铺碾压，防止出现压实压实死角。待养护期到后反挖，取出临时钢板井盖，浇筑井。

In order to make the manhole cover and well body of the inspection well connect well with each other, the well ring is set up on the top of the well body, and C50 steel fiber concrete is used for quick setting concrete. The elevation of well ring is generally the same as that of cement stabilized layer. During construction, a thick steel plate (or other load-bearing material) is placed in the wellhead to cover the wellhead, as a temporary well cover, and a mark is made and rolled up with the cement stabilized layer to prevent the compaction and compaction of the dead angle. After the maintenance period is back, dig out the temporary steel cover and pour the well.

2.5检查井井盖安装

2.5 inspection well cap installation

井盖安装和沥青路面的摊铺配合完成。一般沥青道路面层分为两层或三层，可利用临时钢板（或其他承重物）覆盖井盖与道路一并摊铺碾压，然后根据井盖大小反挖，再进行井盖安装，安装完成后填充压实周

The installation of the manhole cover and the paving of the asphalt pavement are completed. The general asphalt road surface layer is divided into two or three layers, and the temporary steel plate (or other load-bearing) can be used to cover the shaft cover and the road, and then the road is spread and rolled, then the well cover is back to the shaft, then the shaft cover is installed, and the compaction week is filled after the installation is completed.