CN102943493A - Method for measuring internal force and deformation of precast pile - Google Patents

Method for measuring internal force and deformation of precast pile Download PDF

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CN102943493A
CN102943493A CN2012105147380A CN201210514738A CN102943493A CN 102943493 A CN102943493 A CN 102943493A CN 2012105147380 A CN2012105147380 A CN 2012105147380A CN 201210514738 A CN201210514738 A CN 201210514738A CN 102943493 A CN102943493 A CN 102943493A
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pile
section
sensor
anchorage head
power transmission
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CN102943493B (en
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邬俊杰
陈锦剑
王建华
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Shanghai Jiaotong University
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Abstract

The invention provides a method for measuring the internal force and the deformation of a precast pile. After a piling procedure is accomplished, a sensor and vertical pile foundation static load experiment equipment which is connected with the sensor are installed; before the next stage of load is exerted, the numerical reading of the sensor under one stage of load is recorded, namely, the relative deformation at an observation point (at which a force transmission rope is connected) and a reference part; the relative deformation is divided by the pile length of the section so as to obtain the relative strain of the observation section relative to a reference plane; the strain difference between two sections is obtained through the strains of two adjacent observation sections relative to the reference plane; and the axial force of the pile body at each anchoring head section is calculated according to the elastic modulus calibration result of the pile body concrete. According to the method for measuring the internal force and the deformation of the precast pile provided by the invention, the sensor is installed after the piling procedure is accomplished, so that the sensor is prevented from being damaged in the piling process, and moreover the measurement precision is high, and the cost can be controlled effectively.

Description

Measure the method for preformed pile internal force and distortion
Technical field
The present invention relates to a kind of method of civil engineering pile foundation technical field of quality detection, be specifically related to a kind of method of measuring preformed pile internal force and distortion.
Background technology
Pile foundation is as a large amount of base forms that adopt of engineering construction at present, and is little except having sedimentation, the bearing capacity advantages of higher, and it also relates to the important component part of structural safety, and therefore the detection for pile foundation is vital.
Main method for the Internal forces test has reinforcing rib meter method and slip micrometer method at present.(1) reinforcing rib meter method: reinforcing rib meter is embedded on the pile body master muscle according to substructure, the ess-strain at the bottom of the detection a certain cross section of pile body and the post.This method of testing principle is simple, testing element is easy to install, but strain that can only measuring point, and the distortion between 2 can only be leaned on deduction, and because reinforcing rib meter is the average internal force of extrapolating stake according to the strain of any on the reinforcing bar, can there be no small error like this.Because the sensor such as reinforcing rib meter need to be embedded in the pile body, in the making of stake and piling process, cause damage easily, and affect test performance and the calibration coefficient of sensor, thereby can be lowered into motility rate and affect test result.In addition, because sensor can not be recycled after pre-buried, belong to medical disposable material, the cost of the test of increase.(2) slip micrometer method: with respect to the reinforcing rib meter method, slip micrometer method can be measured the strain under all each point axis directions loads at different levels on the whole pile body axis continuously, and can effectively revise and float zero.Measuring point is many although it has, and continuity is good, and precision advantages of higher, the shortcoming that its cost is high also are the factors that needs are considered.
Patent 200910056699.2 provides a kind of method, by vertical service sleeve or directly at the pile body longitudinal drilling, installs and measures system at pile body in sleeve pipe or boring, and this measuring system is comprised of anchor head, multiple position extensometer, extension bar and force pipe.According to the vertical deformation between adjacent two the anchor head positions with all of stake top vertical displacement observed result, a layering frictional resistance, stake end bearing power and the anchor head of each soil layer of reckoning stake side are buried the vertical displacement of section underground, thereby realize Internal forces and section vertical displacement measurement.
All there is at least one shortcoming in the above traditional method.For example, the former precision is not high enough, and because sensor is installed first, produces easily damage problem; Although latter's precision can reach requirement, high cost, economical not.
Summary of the invention
The problem that the object of the invention is to solve in the prior art low precision when measuring preformed pile internal force and distortion or high cost.
To achieve these goals, the present invention proposes a kind of method of measuring preformed pile internal force and distortion, it is characterized in that, may further comprise the steps: determine observation point anchorage head quantity and the position of burying section underground; Service sleeve on the pile body of described preformed pile is vertical; The benchmark anchorage head that has the hole is installed on stake top at described preformed pile; In the described position of burying section underground described observation point anchorage head is installed, and described observation point anchorage head and described sleeve pipe are fixedly linked, if run into the situation of pile extension, one anchoring temporarily point then is set in stake the last period, be used for fixedly passing the power transmission rope of pile extension section, the hole of passing through for described power transmission rope is set on the described anchoring temporarily point; The operation of driving piles if need pile extension, is then proceeded the pile extension operation; One sensor is provided, by the hole on the described benchmark anchorage head, is installed on the described power transmission rope, and described sensor is demarcated; The pile foundation vertical static loading experiment equipment that links to each other with described sensor is installed, is applied before the next stage load, record the sensor reading under certain grade of load, namely this power transmission rope connects the relative deformation of observation point place and benchmark place; This relative deformation is long divided by this section stake, obtain measuring frequency section with respect to the relative strain of datum, with the strain of adjacent two measuring frequency sections with respect to datum, obtain the strain value between these two sections, according to pile concrete modulus of elasticity calibration result, calculate the pile body axle power of each anchorage head section part.
Optionally, may further comprise the steps: the first step, determine that according to geotechnical investigation report, construction note, regional experience and the designing requirement in place, test pile place suitable observation point anchorage head quantity and its bury cross section place underground; Second step, casing axis should be parallel to the pile body longitudinal axis, and sleeve pipe should mate with the anchorage head of selecting; Burying sleeve pipe underground should be arranged symmetrically with along the cross-section center axis direction, the benchmark anchorage head of installing at place, stake top, in the middle of need perforate, convenient at last sensor is packed into, at determined section part the observation point anchorage head is installed, anchorage head and sleeve pipe is firmly fixing, if meet the situation that pile extension is arranged, then the anchoring temporarily point need to be set in stake the last period, convenient fixing need to be passed the power transmission rope of pile extension section, the anchoring temporarily point needs perforate, so that the power transmission rope can be passed through; The 3rd step began piling, according to normal construction process stake was squeezed into, if need pile extension, also carried out as requested pile extension; The 4th step after stake is squeezed into, by the hole of stake top benchmark anchorage head, installed to sensor on the power transmission rope, and sensor requires can free-hand perforate by the reference point anchorage head to pack in the sleeve pipe, and is stuck on the power transmission rope; The 5th step, conventional pile foundation vertical static loading experiment equipment is installed, record according to a conventional method load after on-test; The 6th step, stable at certain grade of load action bottom offset, apply before the next stage load, record the sensor reading under certain grade of load, namely this power transmission rope connects the relative deformation of observation point place and benchmark place, this relative deformation is long divided by this section stake, obtain measuring frequency section with respect to the relative strain of datum, with the strain of adjacent two measuring frequency sections with respect to datum, obtain the strain value between these two sections, according to pile concrete modulus of elasticity calibration result, calculate the pile body axle power of each anchorage head section part.
The useful technique effect that the present invention measures the method for preformed pile internal force and distortion is: the present invention measures the method for preformed pile internal force and distortion and takes sensor installation after finishing the piling operation, avoided sensor impaired in the piling process, and certainty of measurement is high, can effectively control cost.
Description of drawings
Fig. 1 is the apparatus structure schematic diagram of the present invention's method of measuring preformed pile internal force and distortion.
The specific embodiment
Below, 1 the present invention is described in further detail by reference to the accompanying drawings.Label among Fig. 1: 1-observation point anchorage head; The 2-sleeve pipe; 3-reference point anchorage head; The 4-sensor; 5-power transmission rope; The temporary fixed point of 6-power transmission rope; 7-pile extension head; The 8-data acquisition instrument.
Please refer to Fig. 1, Fig. 1 is the apparatus structure schematic diagram of the present invention's method of measuring preformed pile internal force and distortion, and the concrete steps of the inventive method are:
(1) determines that according to geotechnical investigation report, construction note, regional experience and the designing requirement in place, test pile place suitable observation point anchorage head quantity and its bury cross section place underground.Observation point anchorage head 1 generally can be embedded in two kinds of heterogeneity soil layers at the interface.
(2) when the system stake, bury sleeve pipe 2 underground.The sleeve pipe material will not limit, but requires casing axis should be parallel to the pile body longitudinal axis, and sleeve pipe 2 should mate with the observation point anchorage head 1 of selecting and reference point anchorage head 3; Burying sleeve pipe underground should be arranged symmetrically with along the cross-section center axis direction.At place, stake top reference for installation anchorage head 3, need perforate in the middle of the benchmark anchorage head 3, conveniently at last sensor 4 is packed into.At determined section part observation point anchorage head 1 is installed, with observation point anchorage head 1, reference point anchorage head 3 is firmly fixing with sleeve pipe 2.With power transmission rope 5 each observation point anchorage head 1 is connected with benchmark anchorage head 3 respectively, if meet the situation that pile extension is arranged, then anchoring temporarily point 6 need to be set in stake the last period, convenient fixing need to be passed the power transmission rope 5 of pile extension section.Anchoring temporarily point 6 needs perforate, so that the power transmission rope can be passed through
(3) begin piling, according to normal construction process stake is squeezed into, if need pile extension, also carry out as requested pile extension.
(4) after stake is squeezed into, by the hole of stake top benchmark anchorage head 3, sensor 4 is put into stake, and be installed on the power transmission rope 5.Transmitting wire by data links to each other with the data acquisition instrument 8 of outside.Install the demarcation of laggard line sensor, be that standard volume inputs to sensor undetermined 4, obtain simultaneously the output quantity of sensor 4, the sensor input and output amount that obtains is compared and treated, thereby obtain the calibration curve of both corresponding relations of a series of signs, obtain the measured result of sensor performance index.
(5) conventional pile foundation vertical static loading experiment equipment is installed, is recorded according to a conventional method load after on-test.
(6) stable at certain grade of load action bottom offset, apply before the next stage load, record the reading of the data acquisition instrument 8 under certain grade of load, i.e. the observation point place that connects of this power transmission rope and the relative deformation δ of benchmark place.This relative deformation δ divided by the long L of this section stake, then can be obtained measuring frequency section for the relative strain ε of datum.ε=δ/L。With the strain of adjacent two measuring frequency sections with respect to datum, then can obtain the strain value between these two sections.dε ii+1i。ε iBe that i observation point anchorage head place is with respect to the strain value of datum.According to pile concrete modulus of elasticity calibration result E=f (ε), pile body cross sectional area A then can calculate the pile body axle power N of each anchorage head section part i=EA d ε i
Although the present invention discloses as above with preferred embodiment, so it is not to limit the present invention.Have in the technical field of the present invention and usually know the knowledgeable, without departing from the spirit and scope of the present invention, when being used for a variety of modifications and variations.Therefore, protection scope of the present invention is as the criterion when looking claims person of defining.

Claims (2)

1. a method of measuring preformed pile internal force and distortion is characterized in that, may further comprise the steps:
Determine observation point anchorage head quantity and the position of burying section underground;
Service sleeve on the pile body of described preformed pile is vertical;
The benchmark anchorage head that has the hole is installed on stake top at described preformed pile;
In the described position of burying section underground described observation point anchorage head is installed, and described observation point anchorage head and described sleeve pipe are fixedly linked, if run into the situation of pile extension, one anchoring temporarily point then is set in stake the last period, be used for fixedly passing the power transmission rope of pile extension section, the hole of passing through for described power transmission rope is set on the described anchoring temporarily point;
The operation of driving piles if need pile extension, is then proceeded the pile extension operation;
One sensor is provided, by the hole on the described benchmark anchorage head, is installed on the described power transmission rope, and described sensor is demarcated;
The pile foundation vertical static loading experiment equipment that links to each other with described sensor is installed, is applied before the next stage load, record the sensor reading under certain grade of load, namely this power transmission rope connects the relative deformation of observation point place and benchmark place;
This relative deformation is long divided by this section stake, obtain measuring frequency section with respect to the relative strain of datum, with the strain of adjacent two measuring frequency sections with respect to datum, obtain the strain value between these two sections, according to pile concrete modulus of elasticity calibration result, calculate the pile body axle power of each anchorage head section part.
2. Internal forces according to claim 1 and deformation measuring device is characterized in that, may further comprise the steps:
The first step determines that according to geotechnical investigation report, construction note, regional experience and the designing requirement in place, test pile place suitable observation point anchorage head quantity and its bury cross section place underground;
Second step, casing axis should be parallel to the pile body longitudinal axis, and sleeve pipe should mate with the anchorage head of selecting; Burying sleeve pipe underground should be arranged symmetrically with along the cross-section center axis direction, the benchmark anchorage head of installing at place, stake top, in the middle of need perforate, convenient at last sensor is packed into, at determined section part the observation point anchorage head is installed, anchorage head and sleeve pipe is firmly fixing, if meet the situation that pile extension is arranged, then the anchoring temporarily point need to be set in stake the last period, convenient fixing need to be passed the power transmission rope of pile extension section, the anchoring temporarily point needs perforate, so that the power transmission rope can be passed through;
The 3rd step began piling, according to normal construction process stake was squeezed into, if need pile extension, also carried out as requested pile extension;
The 4th step after stake is squeezed into, by the hole of stake top benchmark anchorage head, installed to sensor on the power transmission rope, and sensor requires can free-hand perforate by the reference point anchorage head to pack in the sleeve pipe, and is stuck on the power transmission rope;
The 5th step, conventional pile foundation vertical static loading experiment equipment is installed, record according to a conventional method load after on-test;
The 6th step, stable at certain grade of load action bottom offset, apply before the next stage load, record the sensor reading under certain grade of load, namely this power transmission rope connects the relative deformation of observation point place and benchmark place, this relative deformation is long divided by this section stake, obtain measuring frequency section with respect to the relative strain of datum, with the strain of adjacent two measuring frequency sections with respect to datum, obtain the strain value between these two sections, according to pile concrete modulus of elasticity calibration result, calculate the pile body axle power of each anchorage head section part.
CN201210514738.0A 2012-12-04 2012-12-04 Method for measuring internal force and deformation of precast pile Active CN102943493B (en)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103967057A (en) * 2014-04-30 2014-08-06 河海大学 Soil body displacement field visualization testing device used in pile sinking process and using method
CN104075664A (en) * 2014-07-02 2014-10-01 中国矿业大学 Shaft deformation rapid scanning and obtaining device
CN104631518A (en) * 2015-01-04 2015-05-20 东南大学 Device and method for monitoring internal force of rear sensor opening steel pipe pile
CN104662442A (en) * 2013-08-16 2015-05-27 皇家飞利浦有限公司 System and method for detecting physical deformation of a pole
CN105133671A (en) * 2015-08-26 2015-12-09 上海交通大学 Device for connecting indoor vertical static load model pile with pressure sensor
CN105696633A (en) * 2016-03-31 2016-06-22 中国电建集团华东勘测设计研究院有限公司 Monitoring system and monitoring method for support effect of slide-resistant piles
CN105821912A (en) * 2016-04-01 2016-08-03 上海筑邦测控科技有限公司 Method for detecting supporting axial force of foundation pit, intelligent foundation pit supporting device and intelligent foundation pit supporting system
CN111576504A (en) * 2020-05-29 2020-08-25 武汉至科检测技术有限公司 PHC pile body internal force testing method based on optical fiber strain and optical fiber layout method
CN111576507A (en) * 2020-05-29 2020-08-25 海安东大岩土桩基工程检测有限公司 Method for measuring displacement and internal force of pile foundation
CN115075309A (en) * 2022-07-27 2022-09-20 河海大学 System and method for testing axial force and side friction resistance of pile body

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3823255B2 (en) * 2004-03-15 2006-09-20 株式会社竹中工務店 Measuring method of axial force of ground improved pile
CN1900434A (en) * 2006-07-25 2007-01-24 南京大学 Distributive optical fiber detecting method and system for prefabricated pile damage
CN101638902A (en) * 2009-08-20 2010-02-03 高飞 Method for measuring pile shaft internal force and cross section displacement in vertical dead-load test of foundation pile
CN102409705A (en) * 2011-09-22 2012-04-11 深圳思量微***有限公司 System for monitoring and pre-warning pile foundation damage in real time

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3823255B2 (en) * 2004-03-15 2006-09-20 株式会社竹中工務店 Measuring method of axial force of ground improved pile
CN1900434A (en) * 2006-07-25 2007-01-24 南京大学 Distributive optical fiber detecting method and system for prefabricated pile damage
CN101638902A (en) * 2009-08-20 2010-02-03 高飞 Method for measuring pile shaft internal force and cross section displacement in vertical dead-load test of foundation pile
CN102409705A (en) * 2011-09-22 2012-04-11 深圳思量微***有限公司 System for monitoring and pre-warning pile foundation damage in real time

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104662442A (en) * 2013-08-16 2015-05-27 皇家飞利浦有限公司 System and method for detecting physical deformation of a pole
US9983313B2 (en) 2013-08-16 2018-05-29 Philips Lighting Holding B.V. System and method for detecting physical deformation of a pole
CN103967057B (en) * 2014-04-30 2016-08-17 河海大学 Soil displacement field visual test device and using method in a kind of pile driving process
CN103967057A (en) * 2014-04-30 2014-08-06 河海大学 Soil body displacement field visualization testing device used in pile sinking process and using method
CN104075664A (en) * 2014-07-02 2014-10-01 中国矿业大学 Shaft deformation rapid scanning and obtaining device
CN104631518A (en) * 2015-01-04 2015-05-20 东南大学 Device and method for monitoring internal force of rear sensor opening steel pipe pile
CN105133671B (en) * 2015-08-26 2017-03-22 上海交通大学 Device for connecting indoor vertical static load model pile with pressure sensor
CN105133671A (en) * 2015-08-26 2015-12-09 上海交通大学 Device for connecting indoor vertical static load model pile with pressure sensor
CN105696633A (en) * 2016-03-31 2016-06-22 中国电建集团华东勘测设计研究院有限公司 Monitoring system and monitoring method for support effect of slide-resistant piles
CN105696633B (en) * 2016-03-31 2018-08-07 中国电建集团华东勘测设计研究院有限公司 A kind of friction pile supporting effect monitoring system and monitoring method
CN105821912A (en) * 2016-04-01 2016-08-03 上海筑邦测控科技有限公司 Method for detecting supporting axial force of foundation pit, intelligent foundation pit supporting device and intelligent foundation pit supporting system
CN105821912B (en) * 2016-04-01 2017-12-22 上海筑邦测控科技有限公司 Detect method, intelligent foundation ditch support meanss and the intelligent foundation pit support system of foundation ditch axial force of the supports
CN111576504A (en) * 2020-05-29 2020-08-25 武汉至科检测技术有限公司 PHC pile body internal force testing method based on optical fiber strain and optical fiber layout method
CN111576507A (en) * 2020-05-29 2020-08-25 海安东大岩土桩基工程检测有限公司 Method for measuring displacement and internal force of pile foundation
CN115075309A (en) * 2022-07-27 2022-09-20 河海大学 System and method for testing axial force and side friction resistance of pile body
CN115075309B (en) * 2022-07-27 2023-08-18 河海大学 Pile shaft axial force and side friction resistance testing system and method

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