At present, it is necessary to strengthen the construction quality control of composite geomembrane, and do a good job in the comprehensive control of personnel, machinery, equipment, materials, etc., Strictly refer to the specific construction preparation procedures, and do a good job in quality research.
Usually, in engineering construction, high-density polyethylene geomembrane is located on the protective layer of nonwoven geotextile. Due to its thin texture, it is easy to burn through the underlying geotextile during hot melt welding, so the geomembrane can be laid by manual welding. The technical indicators of geomembrane shall be strictly controlled, and the control of raw materials shall be strengthened on the premise of ensuring the quality. Generally speaking, when carrying out the specific construction scheme of the composite geomembrane, the first thing to do is to control the climate. The preferred temperature is between 5 ℃ and 40 ℃. The laying of the composite geomembrane is vulnerable to temperature. When the temperature is low, the geomembrane shall be laid tightly. On the contrary, the composite geomembrane is loosely laid to avoid operation in hot seasons.
The laying of composite geomembrane shall meet the requirements of technical specifications. Before operation, there should be acceptance certificates of relevant civil works, and the dimensions must be measured before cutting the composite geomembrane. Especially in corners or complex areas, minimize the degree of jointing. In the laying operation, avoid wrinkles caused by manual operation, and the temperature is low. Try to lay to avoid distortion, overlap and other problems. If the tensile range is exceeded, local cracks or top damage will occur
The anti scour groove is generally a rockfill structure, with the top of the groove flush with the top surface of the apron. The elevation of the groove bottom depends on the high level of scouring, excavation and the number of rockfill. There is no transition layer between the traditional scour control trough and the riverbed foundation soil, and the rockfill directly falls on the riverbed foundation soil. The riverbed foundation soil is prone to erosion damage, and the sand will sink away from the rock. It is often necessary to add riprap to the scour control trough, otherwise the safety of the apron will be affected. The geotextile is laid between the rockfill structure of the scour control trench and the riverbed foundation soil, which can effectively protect the foundation soil from erosion damage.
Many sluices are set along the Liuxi River embankment to ensure that the water does not flow back into the tributary when the water level is high. The soil at the outlet of the sluice is mostly silty fine sand and silt, which is prone to erosion damage. In the original design, there was only riprap in the downstream apron of the stilling basin. After several heavy rains in the flood season, the riprap was quickly washed away, and the riverbed foundation soil was also washed away, affecting the safety of the sluice. Later, it was designed to lay a layer of non-woven geotextile at the bottom of the apron and the anti scour trough, and then lay gravel on the geotextile before placing gabions. After this reconstruction, the outlet section of the sluice has no large scouring deformation. For river sections requiring bottom protection and toe protection in front of embankment with severe water scouring, geotextile can also be set between the protective structure and the foundation soil to protect the foundation soil. But for the common riprap construction, the damage effect of riprap on geotextile should be studied and considered in the design. The allowable bearing capacity is 40kPa, and the compression coefficient is greater than 0.5/MPa. The project is close to the Pearl River estuary, and the cofferdam has high requirements for wind and wave erosion resistance.
Width of rubber waterstop: 250mm, 300mm, 320mm, 350mm, 400mm, 450mm
Thickness: 6mm, 8mm, 10mm, 12mm, 300 × 6300 × 8300 × 10320 × 6320 × 8, 320 × 10350 × 6350 × 8350 × 10400 × 8, 400 × 10400 × 12
six hundred and fifty-one ~Type 659 Selection of rubber waterstop, product applicability and use requirements
1. 651 ~Type 659 Selection of waterstop
The selection of waterstop shall be based on the importance level of buildings, deformation amount of deformation joints, water pressure, use environment and price of waterstop
① Consider the impact of contact medium, such as acid, alkali, oil and other types of corrosion;
② Mould resistance: the mould resistance of waterstop shall be considered to be above Grade II;
③ Service conditions, such as temperature and other influencing factors. Section size. When the structural section size is greater than 500 mm, the width of the waterstop shall not be less than 300 mm
2. Product applicability of rubber waterstop
The series of waterstop products produced by our company are widely used in various types of concrete structures, such as water retaining dams, reservoirs, subways, culverts, tunnels and other underground projects. In these projects, there are deformation joints during pouring due to the failure of continuous pouring, or the deformation of the foundation, or the thermal expansion and contraction of the concrete components caused by temperature change, Construction joints. The leakage prevention problem of these joints should be solved by pouring rubber waterstops at the deformation joints, which can not only prevent groundwater from leaking into the building structure, but also prevent water inside the building from leaking to the outside
