阅读说明：本技术 深基坑与临边基础工序同步施工的方法 (Method for synchronous construction of deep foundation pit and edge foundation process ) 是由 刘艳鹏 李雷 周曹国 于 2020-11-16 设计创作，主要内容包括：本发明涉及一种深基坑与临边基础工序同步施工的方法,步骤一、地质勘察；步骤二、施工前准备；步骤三、深浅基础同步施工：开挖地下管廊之前,先行将排水沟挖好,沿路的一侧形成缓坡形式的排水渠道,由浅到深从基坑边至厂区主路排水沟；由于该区域地质条件多为岩石,地下管廊深基坑在破凿的同时,将坑边厂房柱基础同时破凿,同步施工。本发明在深基坑基础与周边浅基础位置相近时,能够各部位同时施工,降低成本,缩短工期。(The invention relates to a method for synchronously constructing a deep foundation pit and a temporary edge foundation process, which comprises the following steps of I, geological exploration; step two, preparation before construction; step three, synchronous construction of deep and shallow foundations: before the underground pipe gallery is excavated, a drainage ditch is excavated, a gentle slope type drainage channel is formed along one side of a road, and the drainage channel is from the side of a foundation pit to a main road drainage ditch of a plant area from shallow to deep; because this regional geological condition is mostly the rock, underground pipe gallery deep basal pit is when breaking the chisel, with the broken chisel simultaneously of hole limit factory building post basis, the synchronous construction. When the deep foundation pit foundation is close to the peripheral shallow foundation pit, all parts can be constructed simultaneously, the cost is reduced, and the construction period is shortened.)

1. A method for synchronous construction of deep foundation pit and adjacent edge foundation process is characterized by comprising the following steps:

step one, geological survey:

1.1, the surface layer of the field in the construction range is composed of fully weathered granite, strongly weathered granite and medium weathered granite in sequence except miscellaneous filling soil and residual soil;

step two, preparation before construction:

2.1 in order to ensure the construction safety of the deep foundation, taking the range of 30m around the foundation as a construction area, and forbidding stacking heavy loads or constructing other buildings in the area;

2.2 the excavation depth of the pipe gallery is 8.1-8.2m, the excavation depth of the column foundation is 4.4m, and the excavation breaking difficulty is large. The working surface of the pipe gallery is long, rain seasons are alternated, the drainage workload and the drainage difficulty are high in the rain and precipitation period, and meanwhile, enough mechanical equipment and personnel are required to be invested for ensuring the flow process;

step three, synchronous construction of deep and shallow foundations:

3.1 before excavating the underground pipe gallery, dig the escape canal in advance, form the drainage channel of gentle slope form along one side on way, from shallow to dark from the foundation ditch limit to the main road escape canal in factory.

3.2 because this regional geological conditions is mostly the rock, underground pipe gallery deep basal pit is when breaking the chisel, with the broken chisel simultaneously of hole limit factory building post basis, the synchronous construction.

2. The method for synchronously constructing the deep foundation pit and the limb foundation process according to claim 1, characterized in that: the geological survey of the first step is specifically as follows: the method comprises the steps of drawing a place topography north, high south and low, large overall fluctuation, and in an exploration stage, the ground elevation of an exploration point is generally 61.03-79.56 m, the maximum elevation difference is 18.53m, and landform units of the drawing place belong to hilly mountain foot landforms. The underground water is mainly bedrock fracture water and mainly exists in weathered rocks. The supply source of the underground water is mainly atmospheric precipitation, and the discharge path is mainly artificial exploitation. During exploration, the buried depth of the underground water level is generally 3.00-8.00 m, stable underground water level buried depth is not seen, the underground water level generally changes along with the change of the terrain, but the water inflow is generally small. According to field drilling data, combining results of in-situ test and geotechnical test data, determining that the site foundation soil can be divided into 7 layers within the investigation depth range, and the deeply foundation falls into 4-3 layers of weathered granite (Pt): the rock core is red in meat, grey green, local grey white, medium-coarse-grain structure, blocky in structure, the main mineral components are quartz and feldspar, the structure is partially damaged, weathering cracks develop greatly, the rock core is mostly broken blocky, hammering sound is crisp, the rock core is mostly weathered spherically, and the rock core taking rate is 65-75%.

3. The method for synchronously constructing the deep foundation pit and the limb foundation process according to claim 1, characterized in that: the construction in the third step is specifically as follows: measuring and positioning → 0m to 4.4m, putting slope according to a coefficient of 1:1 → -4.4m (forming the elevation of the column foundation and expanding into a first-layer platform) -, -8.2m, putting slope according to a coefficient of 1:1 → -8.2m, breaking (forming the elevation of the base, namely the underground pipe gallery foundation and expanding into a second-layer platform) → paying off → construction of the underground pipe gallery structure;

if more groundwater or construction in rainy season is met in the excavation process, a water pump and machinery need to be added properly, and the excavation progress is guaranteed to be carried out smoothly. When rock is broken, the elevation of the bottom of the foundation pit is not controlled well, so that a 10cm manual groove is reserved before the bottom of the foundation pit is excavated, the foundation is prevented from being disturbed by overexcavation, when the bottom of the pit is cleared, the bottom of the pit needs to be cleared to the designed elevation, and a height-marking pile is arranged in the groove to ensure that the bottom of the pit is flat;

forming a step-shaped foundation pit bottom after excavation;

in the foundation ditch that has the step form, carry out factory building basis and underground pipe gallery's construction operation in step on different terrace surfaces in proper order.

Technical Field

The invention relates to the technical field of civil engineering, in particular to a method for synchronously constructing a deep foundation pit and a near-edge foundation process.

Background

In recent years, in steel-making engineering construction, deep foundation pit construction is particularly prominent, the condition that a deep foundation pit and a shallow foundation pit are adjacent to each other basically exists in both a cyclone pool and an underground pipe gallery, the traditional construction process usually adopts the principle of 'deep first and shallow later', the method has the biggest defects of long construction period, the construction difficulty of the deep foundation pit is large in excavation difficulty, long in construction period and high in danger, and collapse easily occurs in the construction process particularly in rainy seasons, so that the whole construction plan is relatively prolonged. Before the construction of the deep foundation pit is not completed, the peripheral shallow foundation cannot be constructed, and even the construction of other specialties is influenced, so that the promotion of the whole project is delayed.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, provides a method for synchronously constructing a deep foundation pit and a near-edge foundation, and solves the problem that a peripheral shallow foundation cannot be constructed before the construction of the deep foundation pit is not finished.

In order to solve the technical problem, the invention is realized as follows:

a method for synchronous construction of deep foundation pit and adjacent edge foundation process is characterized by comprising the following steps:

step one, geological survey:

1.1, the surface layer of the field in the construction range is composed of fully weathered granite, strongly weathered granite and medium weathered granite in sequence except miscellaneous filling soil and residual soil;

step two, preparation before construction:

2.1 in order to ensure the construction safety of the deep foundation, taking the range of 30m around the foundation as a construction area, and forbidding stacking heavy loads or constructing other buildings in the area;

2.2 the excavation depth of the pipe gallery is 8.1-8.2m, the excavation depth of the column foundation is 4.4m, and the excavation breaking difficulty is large. The working surface of the pipe gallery is long, rain seasons are alternated, the drainage workload and the drainage difficulty are high in the rain and precipitation period, and meanwhile, enough mechanical equipment and personnel are required to be invested for ensuring the flow process;

step three, synchronous construction of deep and shallow foundations:

3.1 before excavating the underground pipe gallery, dig the escape canal in advance, form the drainage channel of gentle slope form along one side on way, from shallow to dark from the foundation ditch limit to the main road escape canal in factory.

3.2 because this regional geological conditions is mostly the rock, underground pipe gallery deep basal pit is when breaking the chisel, with the broken chisel simultaneously of hole limit factory building post basis, the synchronous construction.

The method for synchronous construction of the deep foundation pit and the adjacent edge foundation process is characterized in that: the geological survey of the first step is specifically as follows: the method comprises the steps of drawing a place topography north, high south and low, large overall fluctuation, and in an exploration stage, the ground elevation of an exploration point is generally 61.03-79.56 m, the maximum elevation difference is 18.53m, and landform units of the drawing place belong to hilly mountain foot landforms. The underground water is mainly bedrock fracture water and mainly exists in weathered rocks. The supply source of the underground water is mainly atmospheric precipitation, and the discharge path is mainly artificial exploitation. During exploration, the buried depth of the underground water level is generally 3.00-8.00 m, stable underground water level buried depth is not seen, the underground water level generally changes along with the change of the terrain, but the water inflow is generally small. According to field drilling data, combining results of in-situ test and geotechnical test data, determining that the site foundation soil can be divided into 7 layers within the investigation depth range, and the deeply foundation falls into 4-3 layers of weathered granite (Pt): the rock core is red in meat, grey green, local grey white, medium-coarse-grain structure, blocky in structure, the main mineral components are quartz and feldspar, the structure is partially damaged, weathering cracks develop greatly, the rock core is mostly broken blocky, hammering sound is crisp, the rock core is mostly weathered spherically, and the rock core taking rate is 65-75%.

The method for synchronous construction of the deep foundation pit and the adjacent edge foundation process is characterized in that: the construction in the third step is specifically as follows: measuring and positioning → 0m to 4.4m, putting slope according to a coefficient of 1:1 → -4.4m (forming the elevation of the column foundation and expanding into a first-layer platform) -, -8.2m, putting slope according to a coefficient of 1:1 → -8.2m, breaking (forming the elevation of the base, namely the underground pipe gallery foundation and expanding into a second-layer platform) → paying off → construction of the underground pipe gallery structure;

if more groundwater or construction in rainy season is met in the excavation process, a water pump and machinery need to be added properly, and the excavation progress is guaranteed to be carried out smoothly. When rock is broken, the elevation of the bottom of the foundation pit is not controlled well, so that a 10cm manual groove is reserved before the bottom of the foundation pit is excavated, the foundation is prevented from being disturbed by overexcavation, when the bottom of the pit is cleared, the bottom of the pit needs to be cleared to the designed elevation, and a height-marking pile is arranged in the groove to ensure that the bottom of the pit is flat;

forming a step-shaped foundation pit bottom after excavation;

in the foundation ditch that has the step form, carry out factory building basis and underground pipe gallery's construction operation in step on different terrace surfaces in proper order.

The invention has the beneficial effects that: in combination with the actual geological condition, all the adjacent column foundations are broken and chiseled out in the process of digging and chiseling the deep foundation pit, so that the earthwork load of the upper side slope is reduced, and the possibility of collapse is reduced; on the other hand, synchronous construction of deep and shallow foundations can be guaranteed, construction can be carried out without waiting for deep foundation backfilling, the construction period and the maintenance period of a deep foundation pit are avoided, the construction period is greatly shortened, and great help is provided for promoting the whole project.

Drawings

The invention is described in further detail below with reference to the following figures and embodiments:

fig. 1 is a schematic view of a foundation pit bottom formed with a step shape after excavation.

Detailed Description

As shown in fig. 1: a method for synchronous construction of deep foundation pit and adjacent edge foundation process comprises the following steps:

step one, geological survey:

1.1, the surface layer of the field in the construction range is composed of fully weathered granite, strongly weathered granite and medium weathered granite in sequence except miscellaneous filling soil and residual soil;

step two, preparation before construction:

2.1 in order to ensure the construction safety of the deep foundation, taking the range of 30m around the foundation as a construction area, and forbidding stacking heavy loads or constructing other buildings in the area;

2.2 the excavation depth of the pipe gallery is 8.1-8.2m, the excavation depth of the column foundation is 4.4m, and the excavation breaking difficulty is large. The working surface of the pipe gallery is long, rain seasons are alternated, the drainage workload and the drainage difficulty are high in the rain and precipitation period, and meanwhile, enough mechanical equipment and personnel are required to be invested for ensuring the flow process;

step three, synchronous construction of deep and shallow foundations:

3.1 before excavating the underground pipe gallery, dig the escape canal in advance, form the drainage channel of gentle slope form along one side on way, from shallow to dark from the foundation ditch limit to the main road escape canal in factory.

3.2 because this regional geological conditions is mostly the rock, underground pipe gallery deep basal pit is when breaking the chisel, with the broken chisel simultaneously of hole limit factory building post basis, the synchronous construction.

The method comprises the following operation steps:

(1) the method comprises the steps of drawing a place topography north, high south and low, large overall fluctuation, and in an exploration stage, the ground elevation of an exploration point is generally 61.03-79.56 m, the maximum elevation difference is 18.53m, and landform units of the drawing place belong to hilly mountain foot landforms. The underground water is mainly bedrock fracture water and mainly exists in weathered rocks. The supply source of the underground water is mainly atmospheric precipitation, and the discharge path is mainly artificial exploitation. During exploration, the buried depth of the underground water level is generally 3.00-8.00 m, stable underground water level buried depth is not seen, the underground water level generally changes along with the change of the terrain, but the water inflow is generally small. According to field drilling data, combining results of in-situ test and geotechnical test data, determining that the site foundation soil can be divided into 7 layers within the investigation depth range, and the deeply foundation falls into 4-3 layers of weathered granite (Pt): the rock core is red in meat, grey green, local grey white, medium-coarse-grain structure, blocky in structure, the main mineral components are quartz and feldspar, the structure is partially damaged, weathering cracks develop greatly, the rock core is mostly broken blocky, hammering sound is crisp, the rock core is mostly weathered spherically, and the rock core taking rate is 65-75%.

(2) Earlier digging through with the escape canal before the piping lane excavation, the water pump is prepared to target in place, avoids the more influence excavation progress of groundwater.

The column foundation is an independent foundation, so that a two-stage slope-releasing and large-excavation mode is planned in combination with the actual situation of a site.

(3) The specific construction process comprises the following steps: measurement positioning → 0m to 4.4m slope release according to a coefficient of 1:1 → -4.4m breaking → -4.4m (forming the elevation of the column foundation and expanding into a first-layer platform) -, -8.2m slope release according to a coefficient of 1:1 → -8.2m breaking (forming the elevation of the base, namely the underground pipe gallery foundation and expanding into a second-layer platform) → pay-off → construction of the underground pipe gallery structure.

(4) If more groundwater or construction in rainy season is met in the excavation process, a water pump and machinery need to be added properly, and the excavation progress is guaranteed to be carried out smoothly. Because rock is broken when chisel, is not good to control foundation ditch bottom elevation, consequently, should reserve 10cm before digging the foundation ditch bottom and clear the groove by the manual work, prevent to surpass and dig disturbance ground, when the hole bottom is cleared up soil, must clear the hole bottom to design elevation, should set up the standard height stake when the groove, guarantee that the hole bottom is level and smooth.

(5) Forming a step-shaped foundation pit bottom after excavation (figure 1);

(6) in the foundation ditch that has the step form, carry out the construction operation of factory building basis 1 and underground pipe gallery 2 in proper order on different terrace surfaces in step.