CN201713810U - Pile foundation structure applied to Karst region - Google Patents

Abstract

The utility model discloses a pile foundation structure applied to a Karst region, which comprises a pile foundation body (10), a supporting body (13) is arranged in the middle of the pile foundation body (10), and a padding layer (7) is arranged at the lower part of the supporting body (13). The pile foundation structure is applied to construct the pile foundation in the Karst region with better developed pile-end horizontal bedrock and ensures the construction safety.

Description

A kind of piling strtucture that is applicable to the karst region

Technical field

The utility model patent relates to a kind of piling strtucture that is applicable to the karst region, refer in particular in the process of karst region excavation pile foundation, run into that the horizontal karst of an end is extremely grown and during the complete relatively situation of ground top rock, at character expanded hole of construction in the ground preferably, it is carried out arrangement of reinforcement and the bed course with certain thickness and rigidity condition is set under expanded hole, expanded hole place supporting body forms, and makes pile foundation middle part supporting body bring into play bearing capacity by design idea, to guarantee engineering safety.

Background technology

During the pile foundation that constructs a bridge in the karst region, because the solution cavity developmental state is very complicated, boring is difficult to reflect fully virtual condition, builds to engineering and brings many difficulties.Though comparatively typical situation is that boring does not disclose solution cavity, construction finds have folder mud and solution cavity to exist in the stake end certain limit, owing to lack good technical scheme, generally takes at present the pile foundation lengthening, until the way punishment that stake is arranged on the complete basement rock.But adopt this method to handle following problem is still arranged: though 1. pile foundation lengthening back supporting capacity increases, stake top rigidity reduces, and the actual bearer proterties is a friction pile, and stake top displacement is difficult to control; 2. in pile foundation when lengthening,, past more deep excavation be difficult more, constructs dangerous and cost is significantly increased; 3. as the ground deep horizontal when the situation that karst is very grown, it will be very difficult finding suitable bearing stratum in the scope of economical rationality; Even 4. stake is embedded complete basement rock, pile end groundwork following and around the solution cavity situation that contains still be difficult to prediction, can't guarantee fully that bearing capacity of pile tip can bring into play by design load.In fact, vertical karst of growing has the feature that is significantly weakened to the deep by the face of land in the ground, but the karst that level is grown then is subjected to lava position and phreatic the influence and certain buried depth is arranged, the normal interior rock mass engineering project proterties of ground top certain limit of meeting is fair in the engineering, and toward the interior all relatively poor complex situations of foundation condition of the longer scope in deep.If can will allow proterties provide some supporting forces in the rock stratum preferably, the pile foundation that can needn't extend simply reduces unnecessary waste, also can better guarantee engineering safety more.

The utility model content

Technical problem to be solved in the utility model provides the piling strtucture that is applicable to the karst region that a kind of energy adapts to the karst region that the horizontal karst of end an is grown installation and can guarantee engineering safety.

In order to solve the problems of the technologies described above, the piling strtucture that is applicable to the karst region that the utility model provides comprises the pile foundation body, is provided with supporting body at described pile foundation body middle part, is provided with bed course in the bottom of described supporting body.

Adopt the pile base construction method that is applicable to the karst region and the piling strtucture thereof of technique scheme, by pile foundation is retrofited, utilize pile body middle part engineering properties preferably rock mass certain supporting force is provided, carrying out reaming at the better position of rock mass, pile body middle part handles, form the middle part bearing surface, bed course with certain thickness and rigidity requirement is set on this bearing surface face then, after forming pile foundation, the middle part bearing surface can provide certain supporting force, can reach the pile foundation that to extend simply, also can better guarantee the purpose of engineering safety.When pile foundation was born vertical uniform load q, because the initial stiffness of reaming place bed course is less, the side friction of pile foundation is performance earlier, and along with the increase of load, reaming place bed course rigidity increases, and the middle part supporting force is performance fully gradually, the bearing capacity of pile foundation value of reaching capacity.

In sum, the utility model is a kind of energy adaptation karst region that the horizontal karst of end is grown installation pile foundation and the pile base construction method that is applicable to the karst region and the piling strtucture thereof that can guarantee engineering safety.

Description of drawings

Fig. 1 is a pile foundation remodeling processing scheme flow chart;

Fig. 2 is a middle part reaming pile foundation carrying schematic diagram;

Fig. 3 is an A place enlarged drawing among Fig. 2.

The specific embodiment

The utility model is described in further detail below in conjunction with the drawings and specific embodiments.

Referring to Fig. 1, Fig. 2 and Fig. 3, be provided with supporting body 13 at pile foundation body 10 middle parts, be provided with bed course 7 in the bottom of supporting body 13.

Referring to Fig. 1, Fig. 2 and Fig. 3, the karst ground is made up of the solution cavity 3 in last overburden layer 1, rock 2 and the ground, adopt the manually digging hole mode to form a hole 4, because the following karst of stake end is very grown, in the rock 2 on top hole enlargement being carried out in stake hole 4 this moment handles, form expanded hole 5 and form bearing surface 6, construction one deck bed course 7 on bearing surface 6 then, behind the 4 interior install reinforcing cages 8 of stake hole, again in expanded hole 5 places artificial colligation expanded hole reinforcing cage 9, last 4 interior placing of concrete form pile foundation body 10 toward the stake hole, and pile foundation body 10 forms supporting body 13 at expanded hole 5 places.

Referring to Fig. 1, Fig. 2 and Fig. 3, when being subjected to pile top load 11, pile foundation body 10 does the time spent, because bed course 7 initial stiffnesses are less, each pile cutoff frictional resistance 12 of pile foundation body 10 is at first brought into play, when pile top load 11 increased gradually, the rigidity of bed course 7 increased gradually, and the bearing capacity 14 of the bearing surface 6 of the supporting body 13 at expanded hole 5 places is performance fully gradually, this pile foundation body 10 reaches the bearing capacity limiting value, to guarantee engineering safety.

Claims (1)

1. a piling strtucture that is applicable to the karst region comprises pile foundation body (10), it is characterized in that: be provided with supporting body (13) at described pile foundation body (10) middle part, be provided with bed course (7) in the bottom of described supporting body (13).

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