Ecuador's largest livelihood water project officially completed

Release time：2019-09-25 11:04Number of visits：151times

Ecuador is the "one belt, one road" Latin American "Silk Road Post". Recently, St. Elena water conservancy project, the country's largest people's livelihood water conservancy project, was officially completed. This is also the first water conservancy project of CSCEC to enter the South American market. After completion, it can guarantee irrigation water for nearly 350000 hectares of land, greatly improving the local situation of watching the sky and working, thus benefiting about 560000 people in Ecuador. China Construction and installation International Engineering Co., Ltd. undertakes 2 dam restoration, 5 irrigation stations demolition and reconstruction, 1 pumping station expansion, 2 pump station operation and maintenance, and 3000 m water supply pipeline fabrication and installation. With one belt, one road, the average age group of young people under 30 years old, with professional skills, has been breaking through the land and opening up wasteland, which has injected new vitality into the local economic development and people's livelihood construction.

"Secret of customs clearance" for 40 meters underwater

How can the project team ensure that the construction scheme is safe when the design data 30 years ago is lost and 40 meters underwater operation is carried out? At the beginning of the preparation of the construction scheme, the CSCEC team encountered the first challenge.

Chonggon reservoir was built in the 1980s, which solved the problem of irrigation draught for 300000 people in the lower reaches. However, due to the lack of maintenance for a long time, there is a great potential safety hazard. Therefore, it is urgent to overhaul and maintain the dam, bottom outlet, intake tower and other infrastructure of the reservoir.

It is the first time for CSCEC to try underwater construction for the intake Gallery of dam drainage bottom outlet with vertical depth of 40m and depth of 200m and surrounding geological conditions. It is the first time for CSCEC to try underwater construction, which is a rare and difficult underwater operation in China. The chief engineer of the project, Hu Chengjun, took over the "battle book". Through many discussions with professional diving team and mechanical and water conservancy experts, and organizing underwater exploration, it is found that the geological structure around the intake Gallery of the reservoir has changed, and there are hidden dangers in its concrete structure. The original plan of setting a gate at the entrance of the gallery is not applicable. Through repeated experiments and discussions, the project team decided to set the plugging door at the end of the corridor at 200m, but it increased the construction difficulty. Through the preparation of detailed construction scheme, redesign of underwater blocking gate structure, technical disclosure and safety first aid escort, not only the underwater blocking gate construction was successfully completed, but also the safety of subsequent construction of dam drainage bottom hole was ensured.

“GRACIAS！” Repair "trouble road" as soon as possible

Every weekend, the chongon dam has become a paradise for local sports enthusiasts, but the dilapidated road of the dam is already pitted. One of the important goals of the project team is to repair the "troublesome road" as soon as possible.

Drilling and analysis of road subgrade, inspection of quarry, exploration of road base, acquisition of subgrade geological information, redesign and modification of asphalt concrete road drawings, strict control of the thickness and compactness of road base materials During construction, the project team has overcome many complex problems. In the first week after the road was opened to traffic, the local people's "Gracias" (Spanish: Thank you) let everyone sweep away the hard work of the past. Before we can rest, azucar, another reservoir 100 kilometers away, has the same problem. Everyone began to work out the plan, transport materials and allocate machinery.

"Chinese standard" and "made in China" exported to South America

The construction of the project requires the expansion of two pumps and 3000 meters of Penstock with a diameter of 1.6 meters. However, the local production capacity is insufficient and there is no steel for the production of penstock. The project manager Li depeng resolutely decides to apply for 10 million yuan to build a modern steel pipe manufacturing and processing plant in the local area.

However, the owner did not agree to use the materials of Chinese standards. The engineers of CSCEC installation and petrochemical engineering branch were sent to the site to recalculate and verify the original design, and established water hammer model analysis to prove the absolute reliability of Chinese standards and Chinese materials to the owner with detailed data. After one month's hard negotiation, the owner finally agreed to purchase Chinese standard Q345R steel plate, which saved 4 million yuan of material cost for the project.

At the same time, the domestic procurement team has been constantly making inquiries and inviting tenders for many equipment needed for the construction of the plant, strictly inspected the bidding manufacturers, and gave priority to the selection of high-quality enterprise suppliers with overseas equipment supply experience and strength, driving more than 50 million yuan of large-scale equipment exported to South America, and the export tax rebate reached 5.5 million yuan.

Challenge "acceleration" in dry and rainy season

The penstock manufacturing plant was successfully built, and the steel plate was also transported to the construction site by sea. The normal production period of 3000m steel pipe and 1200 steel plate takes 5-6 months. However, the penstock is installed in the wild, and the construction road is blocked. January to march is the local rainy season, so the construction process is very difficult.

The CSCEC team adopts the day and night shift construction mode, with 20 hours of continuous manufacturing operation and 4 hours of nondestructive testing. It takes only two and a half months from trial production to the completion of the last steel pipe. Foreign owners repeatedly praise: "the Chinese builders are really amazing!"

When the production of penstocks is in full swing, it has encountered the land acquisition problem left over by the owners 20 years ago. Li depeng hired a lawyer to express his reason and emotion, so that the landlords and guayas provincial government could feel the friendship of Chinese builders for their infrastructure transformation and upgrading. Finally, without any compensation for land acquisition, the project team successfully completed the excavation, installation and backfilling of 3000m penstock through five landlords and one nature reserve before the rainy season Work.

As scheduled, the rain failed to stop the progress of the installation personnel of CSCEC. From January to March, the project team successfully completed the construction output value of 6 million US dollars through the relay of raincoats, rain shoes, construction vehicles and ginger soup. "We have full confidence in the Chinese construction management team," said Humberto cholango, Minister of water resources of Ecuador, when inspecting the project.

Solving the problem of water pump maintenance

Four large water pumps have been used for 20 years as an important guarantee of water source. Most of the parts are seriously worn out. Two of them have been unable to start up, and only a few drawings can not guide the maintenance of pump sets. In order to avoid damage to the equipment caused by forced dismantling, the project team formulated a strict mechanical maintenance plan, defined the disassembly and reassembly procedures of the pump set, repeatedly compared and adjusted the mechanical maintenance plan, and produced accessories for the water pump 20 years ago, and went to the site for supervision and acceptance.　　

The team used penetrant inspection method to detect the status of equipment parts, and used epoxy ceramic filler to repair the damaged parts, which not only reduced the construction difficulty, but also greatly improved the construction efficiency. The original plan of 90 days of construction period of two pumps, and finally only 35 days to complete the task.

One belt, one road, 22 months, 7 major operation areas and 16 construction sites, and China Construction, with the first-class quality and professional technology, will break the land and polish the brand along the "one belt and one road", and will inject new vitality into the local economic development and people's livelihood construction. From cultural integration to one win win win, one belt, one road, one new road to the construction of the "one belt and one road", is built from the dream to the common people. (contributed by CSCEC installation)