In the construction of municipal road drainage projects,pipe jacking construction is a relatively common construction method.This construction technology can avoid a large amount of excavation work,improve drainage co...In the construction of municipal road drainage projects,pipe jacking construction is a relatively common construction method.This construction technology can avoid a large amount of excavation work,improve drainage construction efficiency,avoid large-scale damage to the road surface,and exert small traffic impact.Therefore,it is currently widely used in drainage construction,but judging from the current actual application situation,there are still many problems that require further improvement.This article mainly analyzes the advantages of and current technical problems in pipe jacking construction technology in detail,explores corresponding solutions,and lays a foundation for the optimization of municipal road drainage engineering construction.展开更多
Accumulation of sediment and silt in the drainage canals is undesirable, yet inevitable occurrence in the course of the use and operation of any drainage canal network. In this study, D-25 drainage canal group, taking...Accumulation of sediment and silt in the drainage canals is undesirable, yet inevitable occurrence in the course of the use and operation of any drainage canal network. In this study, D-25 drainage canal group, taking place in the Nazilli irrigation system with an area of 1165 ha is the only system where all planned activities have been completed. It has been determined that the drainage system was constructed according to original drainage project. The depth of accumulated sediment in the drainage canals in the research area was determined from the difference between the measured elevation and the elevation given in the design projects. The reasons for siltation in the D-25 drainage canal group have been studied by looking at the results of the elevation measurements made in 2010-2012. The measurements made in D-25 drainage canal group showed that there were significant differences between the actual structure (bridge, culvert, and conduit) bottom elevations and the elevations given in the design projects. In addition, the length of some canals would not coincide with the design project either. 83.3% (93.3% in length) of the canals had differences in structure bottom elevations. Of the total 55 structures 45 (81.8%) had a 0.10 m or more difference in bottom elevation from the project. Of the erroneous structures 73.3% had an average of 0.40 m, and 26.7% had an average of -0.25 m difference in bottom elevations from the design projects.展开更多
Until 1957, the Hula Valley was covered by swampy wetlands and a shallow lake, Lake Hula. In the 1950s, the valley was drained and 6000 ha of land was converted to agricultural development. Seven years later, the Nati...Until 1957, the Hula Valley was covered by swampy wetlands and a shallow lake, Lake Hula. In the 1950s, the valley was drained and 6000 ha of land was converted to agricultural development. Seven years later, the National Water Carrier was inaugurated, granting the only natural freshwater lake in Israel, Kinneret, a national drinking water reservoir function. Agricultural cultivation in the Hula Valley faced significant challenges. A reclamation project, the “Hula Project” (HP), was implemented. Thirty (1994-2024) years of HP management are summarized. TP and TN migration data from the Hula Valley southward into Lake Kinneret was approved as not threatening its water quality. During 40 years of post-drainage period underground fire, heavy dust storms were frequently followed by soil subsidence. Nevertheless, as a result of the HP renovated management, those nuisances faded away and significantly declined. Immediately after drainage, as a result of organic Peat oxidation, a great stock of nitrates in the upper layers was formed. Since the mid-1990s, when nitrogen deficiency was developed and Cyanobacteria replaced the bloom-forming Peridinium dominancy, surplus nitrate input has not threatened Kinneret water quality. The hydrological-eco-touristic component of the reclamation project (HP), Lake Agmon-Hula (LAH) became a successful tourist attraction and also an additional nutrient source through submerged vegetation. Two Peat soil areas of land have been denied: the central and the eastern blocks. Soil moisture enhancement, especially that of the Peat soil block, initiated the lowering of the TP migration range and consequently extra water allocation was assigned for summer irrigation (the “Peat Convention Agreement”). Surface, underground seepage and river discharge flows of freshwaters from the Golan Heights into the Hula valley diluted the concentration of migrated TP concentration contributed by the eastern Peat block.展开更多
This paper introduced the construction of the pumped-storage power station （PSPS）. In the excava- tion of underground power house, the principle of excavation in thin layer and support in time with real time monitor...This paper introduced the construction of the pumped-storage power station （PSPS）. In the excava- tion of underground power house, the principle of excavation in thin layer and support in time with real time monitoring are adopted. The excavation blasting parameters are adjusted timely. Through these, the excavation quality can be guaranteed, the surrounding rock can be prevented from being damaged and the deformation of power house side wall can be controlled. Five security defense lines have been adopted to solve anti-seepage and drainage in the major underground projects.展开更多
文摘In the construction of municipal road drainage projects,pipe jacking construction is a relatively common construction method.This construction technology can avoid a large amount of excavation work,improve drainage construction efficiency,avoid large-scale damage to the road surface,and exert small traffic impact.Therefore,it is currently widely used in drainage construction,but judging from the current actual application situation,there are still many problems that require further improvement.This article mainly analyzes the advantages of and current technical problems in pipe jacking construction technology in detail,explores corresponding solutions,and lays a foundation for the optimization of municipal road drainage engineering construction.
文摘Accumulation of sediment and silt in the drainage canals is undesirable, yet inevitable occurrence in the course of the use and operation of any drainage canal network. In this study, D-25 drainage canal group, taking place in the Nazilli irrigation system with an area of 1165 ha is the only system where all planned activities have been completed. It has been determined that the drainage system was constructed according to original drainage project. The depth of accumulated sediment in the drainage canals in the research area was determined from the difference between the measured elevation and the elevation given in the design projects. The reasons for siltation in the D-25 drainage canal group have been studied by looking at the results of the elevation measurements made in 2010-2012. The measurements made in D-25 drainage canal group showed that there were significant differences between the actual structure (bridge, culvert, and conduit) bottom elevations and the elevations given in the design projects. In addition, the length of some canals would not coincide with the design project either. 83.3% (93.3% in length) of the canals had differences in structure bottom elevations. Of the total 55 structures 45 (81.8%) had a 0.10 m or more difference in bottom elevation from the project. Of the erroneous structures 73.3% had an average of 0.40 m, and 26.7% had an average of -0.25 m difference in bottom elevations from the design projects.
文摘Until 1957, the Hula Valley was covered by swampy wetlands and a shallow lake, Lake Hula. In the 1950s, the valley was drained and 6000 ha of land was converted to agricultural development. Seven years later, the National Water Carrier was inaugurated, granting the only natural freshwater lake in Israel, Kinneret, a national drinking water reservoir function. Agricultural cultivation in the Hula Valley faced significant challenges. A reclamation project, the “Hula Project” (HP), was implemented. Thirty (1994-2024) years of HP management are summarized. TP and TN migration data from the Hula Valley southward into Lake Kinneret was approved as not threatening its water quality. During 40 years of post-drainage period underground fire, heavy dust storms were frequently followed by soil subsidence. Nevertheless, as a result of the HP renovated management, those nuisances faded away and significantly declined. Immediately after drainage, as a result of organic Peat oxidation, a great stock of nitrates in the upper layers was formed. Since the mid-1990s, when nitrogen deficiency was developed and Cyanobacteria replaced the bloom-forming Peridinium dominancy, surplus nitrate input has not threatened Kinneret water quality. The hydrological-eco-touristic component of the reclamation project (HP), Lake Agmon-Hula (LAH) became a successful tourist attraction and also an additional nutrient source through submerged vegetation. Two Peat soil areas of land have been denied: the central and the eastern blocks. Soil moisture enhancement, especially that of the Peat soil block, initiated the lowering of the TP migration range and consequently extra water allocation was assigned for summer irrigation (the “Peat Convention Agreement”). Surface, underground seepage and river discharge flows of freshwaters from the Golan Heights into the Hula valley diluted the concentration of migrated TP concentration contributed by the eastern Peat block.
文摘This paper introduced the construction of the pumped-storage power station （PSPS）. In the excava- tion of underground power house, the principle of excavation in thin layer and support in time with real time monitoring are adopted. The excavation blasting parameters are adjusted timely. Through these, the excavation quality can be guaranteed, the surrounding rock can be prevented from being damaged and the deformation of power house side wall can be controlled. Five security defense lines have been adopted to solve anti-seepage and drainage in the major underground projects.
