At 21:50 on December 12, about 500 square meters of property development land collapsed at the lucuo intersection of Xiamen Metro Line 2, causing water pipe to burst. Two cars were trapped on the site and the personnel on board were evacuated safely. No casualties have been found and measures are being taken to deal with it.
According to xiamen Daily, the public security, fire, water and other departments have arrived at the scene and are actively organizing the rush repair. Traffic police on the scene, no traffic congestion occurred.
On the evening of December 3, the latest news of the landfall in Panyu Avenue, Guangzhou city, the scene of the exposure, Panyu Avenue south to the north of the south village in Guangzhou Panyu pavement ground collapse, the current collapse of the ground has been timely backfill, fortunately no casualties.
At about 10 a.m. on August 28, a leakage occurred in the construction of the connecting passage between Baoxanqiao Station and Jianguo North Road station of Subway Line 5, which caused the road collapse of Jianguo North Road (Stadium Road - Fengqi section), accompanied by some gas leakage.
The formation causes of surface collapse are complex and there are many types. The common classification includes natural collapse and man-made collapse.
The former is caused by the surface rock and soil due to natural factors, such as earthquake vibration, infiltration of rainfall into the ground, dead weight pressure, underground erosion and tunneling, etc. The latter is the ground collapse caused by human action, such as water inrush in underground mining, drainage of tunnel or construction, a large number of groundwater exploitation, reservoir water diversion and so on. In these two categories, according to the specific inducing factors that cause collapse can be further divided into many types, such as earthquake collapse, mine goaf collapse, rainfall infiltration collapse, drainage collapse, pumping collapse, water storage collapse, ground load collapse, blasting and other vibration collapse.
5 effectively prevent scaffold collapse during construction
The foundation construction must have the protection plan, the foundation pit depth exceeds 5m, must have the special support design. Scaffolding before use also pay attention to the following content.
1. Ensure the stability of the slope. When excavating trench, foundation pit, etc., the slope slope shall be fully released according to the soil quality and excavation depth, etc. If the site is not allowed to release slope for excavation, solid wall support or support structure system shall be set up. The distance between excavated soil stacking and the edge of pits and grooves shall not be less than the design requirements, and the stacking height shall not exceed 1.5m. In the process of excavation, the soil stability of the side wall should be checked frequently. If cracks, looseness or support are found, measures should be taken at any time.
2. The excavation sequence shall conform to the provisions of construction organization design. Follow the principle of excavating layer by layer from top to bottom.
3. Drain and lower the water table. When excavating earthworks lower than the groundwater level, drainage or precipitation measures should be determined according to geological data and excavation depth, and groundwater should be effectively treated in the whole process of underground construction to prevent collapse.
Operators must strictly follow safe operation procedures. Before the operation, to check the slope soil changes, cracks should be timely excavation. Take breaks on the ground to prevent the slope from collapsing or being buried. No earth wall support or other supporting facilities shall be removed.
4. Monitoring measures. Check the slope and support frequently, take measures in time if any abnormity is found, and inform the underground workers to evacuate, so as to prevent the soil from collapsing and causing casualties.
5. Support facilities to remove scaffolding. It should be carried out in accordance with the provisions of the construction organization design, usually from bottom to top, with the process of filling soil, filling and dismantling layer by layer, not once to the top.