Excavation of mineral resources within the construction red line

7. It can exceed the red line of buildings. Many buildings are designed and built according to the red line in the history of architecture. When excavating the foundation, it must exceed the red line of buildings. There are provisions that can not exceed the red line of land use. Article 4.2.1 of general principles for design of civil buildings stipulates that buildings and ancillary facilities shall not be constructed in a way that highlights the red line of road and land use ¨¨¨ Including structural retaining pile, retaining wall, basement, basement floor and its foundation, septic tank, etc.

8. Of course not. The solutions are as follows: 1. To use the land, 2. If the land is not allowed to be expropriated, it is necessary to design and change the slope ratio or change the line or do retaining measures.

9. The red line of land use refers to the boundary line between the land parcel and the surrounding roads and critical land parcel. According to the planning, sunshine, fire protection and other requirements of the local planning bureau, the scope of land use behind the road and adjacent land is the building property line. Permanent buildings can only be built within the red line.

10.

The mineral resources of nonmetallic building materials in Shenzhen are abundant and widely distributed. According to its use, it can be divided into building stone, decorative materials and building materials

Building stone is the dominant mineral resources in Shenzhen with abundant reserves. The main stone minerals are granite, migmatite, metamorphic complex (migmatite, gneiss, metamorphic sandstone, etc.) and hard rocks such as volcanic rocks

The available stone resources are mainly distributed in low mountain and hilly areas. In terms of mineral types and distribution areas, the most important mineral type is Mesozoic granite stone, which is widely exposed in the special zone, Bao'an and Longgang areas. In the special zone, it is mainly distributed in Shekou and meishajian, mainly composed of medium and coarse-grained granite, with a small amount of fine-grained granite; In Bao'an District, it is mainly distributed in Xixiang, Shiyan and Longhua districts, and in the low mountain area with Yangtai mountain as the center, in which medium and coarse-grained granites are the main ones, and only a small amount of fine-grained granites are distributed in datougang of Gongming and southern Guanlan; In Longgang District, it is mainly distributed in the mountain ranges on both sides of Buji and Pinghu, the mountain ranges in the south of Henggang Pingshan, the mountain ranges along the western coast of Dapeng Peninsula, the junction of Pingshan and Kengzi, and the Longxi mountain range in the northwest of Pingdi. The migmatite is mainly distributed in Xiaonanshan and antuoshan in the special zone, and in Damaoshan, miaoziding, mukengding and dayanshan in Bao'an District. The metamorphic complex is mainly distributed in Guangming, Gongming and Songgang areas in the northwest of Bao'an District, to the north of tianxinshan Yuping Kuiyong highway in the east of Longgang District. Volcano rocks are mainly distributed in the Wutong Mountain and the seven Niangshan area, mainly composed of tuff lava, rhyolite and quartz porphyry. p> In addition, Furong quarry is the only diabase quarry in Shenzhen

after the establishment of Shenzhen Special Economic Zone, e to the rapid development of urban and rural construction, there is a huge demand for building stone, and e to the better mining conditions, a large number of stone yards are mined after the completion of the census work. Quarries used to blossom everywhere, and there were at most 600 quarries. However, with the social and economic development of Shenzhen and the continuous improvement of urban environmental protection and landscape requirements, the small and many stone stopes all over the urban and rural areas of Shenzhen have been unable to meet the needs of urban and rural construction and development. Therefore, by the end of 2006, most of the quarries in Shenzhen had been closed, and comprehensive renovation, reclamation and greening had been carried out. According to the general plan of mineral resources of Shenzhen (2002-2010), the exploitation of building stones in Shenzhen should be strictly limited to 12 stone mining areas. The Department of land administration has made a new plan for the layout of quarries in the whole city and worked out the forbidden and restricted mining areas. Since 2007, only 12 quarries within the limited mining area have been retained (currently, 9 quarries are actually mined), and the scale must reach 50 × More than 10 < sup > 4 < / sup > m < sup > 3 < / sup > / A, with reserves of 300 × 10 < sup > 4 < / sup > m < sup > 3 < / sup > above. By 2010, the annual total amount of stone mining will be controlled at 2000 × 10⁴m³

See table 1-9-4

table 1-9-4 for the existing quarries in the restricted mining area of Shenzhen City

(II) the occurrence conditions and basic characteristics of stone materials

Shenzhen quarries are mainly distributed in the weathering and denudation landform area, most of which are exposed or shallow buried, generally the thickness of weathering crust is 5-12m, but different lithology will have some differences. The basic characteristics of main stones are shown in table 1-9-5

table 1-9-5 basic characteristics of stone materials

1) filling materials: mainly used for land reclamation, site filling and leveling

2) masonry materials: corner stone and rubble meeting certain specifications are mainly used for wharf, embankment, retaining wall and other masonry construction sites

3) Road (ground) foundation bedding material: Crushed Stone less than 5cm and stone powder less than 05cm or more than 05cm are mainly used for road subgrade cushion, building foundation cushion or replacement material

4) concrete aggregate: mainly used for pre mixed concrete and prestressed concrete pipe pile materials

Facing materials: Granite and marble with complete rock mass, uniform structure and beautiful color and texture can be used as raw materials for paving slabs and stone columns

In addition, the diabase stone proced by Furong quarry in Pinghu can be used as high-grade (Expressway) pavement material, which has been used in many provincial and municipal high-quality key projects, and has filled the blank of SMA pavement materials in Guangdong and Shenzhen

(4) calculation of stone reserves the calculation of stone reserves of quarry is based on the red line boundary of the mining area as the calculation boundary and the end interface elevation of the mining design as the calculation bottom boundary. The calculation method is vertical section method, which is divided into calculation blocks and calculated according to the volume calculation formula of wedge or ladder

(5) mining technology and method of stone material. The height of steps is generally 20-40 M; The width of the platform is 30-55 m, and the angle of the temporary slope is controlled at 40 °～ seventy ° between. At present, the quarry has been mechanized scientific mining, has a relatively complete proction line, the annual output has reached 30% × 10 < sup > 4 < / sup > m < sup > 3 < / sup > above

(VI) the impact of stone mining on the environment and natural landscape

1. Vegetation damage and soil erosion

the quarries in Shenzhen are open-pit mining, the quarries need to excavate mountains, cut down trees, strip topsoil, and the waste materials also need to occupy a certain space. At the same time, it is necessary to build supporting roads, houses and other facilities, which will directly damage the vegetation. Generally, the vegetation coverage area destroyed by quarries is about 5-10 times of that of pits. Due to the stripping of topsoil, the pit forms a slope. Under the climatic conditions of abundant rainfall, heavy rain and concentration, soil erosion (soil erosion) is very easy to occur. According to statistics, the damage area of obvious soil erosion caused by quarry is about 1.8 times of the pit mouth area

Land occupation the proction and construction of quarries need to occupy a certain amount of land, even arable land. Including stone mining face, stone proction and stacking site, waste disposal site, proction and management buildings (structures) and transportation roads and sites, etc. all need to occupy a lot of land

3. Environmental pollution

environmental pollution mainly refers to noise pollution caused by mining blasting and gravel machine proction, st pollution caused by mining and finished proct proction, as well as pollution of surface water and underground water caused by oil pollution of mechanical equipment and domestic waste

4. Impact on natural landscape

quarries destroy the integrity of the mountain, destroy vegetation, and are generally located at high places or near the roadside, so it is difficult to renovate ring mining, so it seriously affects the surrounding landscape

at present, the land and planning departments of Shenzhen City have carried out comprehensive planning and renovation on the quarries, closed most of the quarries, and demarcated the no mining area and limited mining area. The closed quarries should be renovated, reclaimed and afforested, and strict requirements for proction, construction and environmental protection should be put forward for the limited number of quarries in the restricted mining area

(7) demand forecast and supply-demand balance analysis of building stone in Shenzhen City

1. Current situation of stone supply in quarries

through on-site investigation and interview by survey and mapping units, the calculation of proction scale of 17 quarries in 12 restricted mining areas before 2006 (table 1-9-6) shows that the stone supply in restricted mining areas in Shenzhen city is about 423 × 10⁴m ³/a In addition, the amount of stone supplied by the social leveling project is about 514.53 × 10 < sup > 4 < / sup > m < sup > 3 < / sup >, the total supply of stone resources in 2006 is about 937.53 × 10⁴m³

table 1-9-6 proction status of quarries in Shenzhen before 2006 table 1-9-7 stone demand in Shenzhen from 2006 to 2010 ×< Sub > 1 < / sub > 0 < sup > 4 < / sup > m < sup > 3 < / sup >

2. Supply and demand analysis of stone market, The annual demand for stone is calculated (table 1-9-7)

table 1-9-6 proction status of quarries in Shenzhen before 2006 table 1-9-7 stone demand in Shenzhen from 2006 to 2010 ×< Sub > 1 < / sub > 0 < sup > 4 < / sup > m < sup > 3 < / sup >

it can be seen from the above table that the demand for stone in 2006 was 796.65 × 10 < sup > 4 < / sup > m < sup > 3 < / sup >, as mentioned above, the supply of stone in 2006 was 937.53 × 10 < sup > 4 < / sup > m < sup > 3 < / sup >, reflecting that the supply of stone materials in the market was slightly greater than the demand or basically balanced in the year. By 2010, according to the above data analysis, the supply of stone materials in Shenzhen may exceed the demand. *** In addition, with the change of land use in Shenzhen, for example, the 2.2km < sup > 2 < / sup > land in Pinghu of Longgang District has been listed in the Financial District of Shenzhen. In this way, e to the change of function, the stone supply in some of the stone limited mining areas may be reced by 200% × 10 < sup > 4 < / sup > m < sup > 3 < / sup > or so. This will lead to a gap in the supply market of stone materials in Shenzhen, and the need to import stone materials from other places

in short, by 2010, Shenzhen will achieve the goal of becoming a national ecological garden city, and some stone limited mining areas will not be able to proce and supply continuously. However, e to the uncertainty of stone supply in social leveling projects, the supply of stone may be in short supply in the future. Therefore, in order to ensure the urban construction of Shenzhen and not be seriously affected by the lack of building stone resources, some suggestions are put forward for the future work:

1) scientific analysis and evaluation of Shenzhen stone market. It includes the analysis and evaluation of the construction stone resource market in the city, and the analysis and evaluation of the stone market outside the city (adjacent areas). On the basis of the above contents, it formulates specific contingency measures for the shortage of stone resources

2) establish Shenzhen stone market information management system. Including the accurate quantity of proction and supply of stone limited mining area, the accurate quantity of supply of social leveling Engineering (including project location, construction nature, earthwork nature and quantity, purpose, etc.) and other relevant information

The utilization rate of stone resources in the city should be improved as far as possible. We should unify the utilization planning of stone resources, expand the mining scale of some quarries, expand the scope of some restricted mining areas or appropriately increase the restricted mining areas on the premise of ensuring that the environment and resources are fully protected

In the surrounding mountainous areas of Shenzhen City, the general survey, investigation and environmental assessment of the reserve base of quarries should be carried out in the areas that do not affect the urban landscape

5) open wide channels, conct in-depth feasibility study on stone resource input outside the city (adjacent areas), and establish relatively stable overseas stone supply base

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