A kind of stress wave multi-point exciting method and multi-point exciting device detecting pile quality
Technical field
The invention belongs to Test Technology of Pile Foundation field, particularly a kind of stress wave multi-point exciting method detecting pile quality, also relate to the multi-point exciting device using the method.
Background technology
At present, low strain dynamic method and Large strain method to the Stress Wave Method of pile integrity detection, wherein most widely used with low strain dynamic method, what low strain dynamic method was the most frequently used is adopt low-yield transient state to push up exciting in stake, the speed time-history curves at a top is obtained by detecting instrument, wave theory analysis is carried out to speed time-history curves, speed time-history curves obtains the position of abnormity point, pile body integrity is judged.Above-mentioned testing process all has regulation in industry standard " architecture foundation pile inspection specifications ", " building foundation inspection criterion ".
When using low strain dynamic method, need at some excitings of stake top hand hammer, some excitings of hand hammer are fast easy to detect as the advantage of traditional excitation method, but its shortcoming is that the effective propagation path of hammer vibration energy is shorter, is difficult to effecting reaction long stake deep abnormal information.If adopt weight exciting to detect pile body integrity, although can more effecting reaction stake Deep Information, but can reduce detection efficiency, inadaptable heavy in a large number Detection task needs.
Summary of the invention
First object of the present invention is to provide a kind of not only can react a deep abnormal information effectively, but also can guarantee the stress wave multi-point exciting method of detection pile quality of detection efficiency.
Second object of the present invention is to provide a kind of multi-point exciting device using the stress wave multi-point exciting method of above-mentioned detection pile quality.
First object of the present invention is realized by following technical measures: a kind of stress wave multi-point exciting method detecting pile quality, it is characterized in that adopting two or more synchronous exciters on stake top, produce two row or two and arrange above synchronous exciter stress waves and transient state interference in pile body, because the energy of ripple and Amplitude-squared are directly proportional, the energy of the vibration reinforced region of the interference stresses ripple after interfering is strengthened, be beneficial to interference stresses wave traveling to stake deep, strengthen compared with the reflection wave signal of single point excitation to make the reflection wave signal detected, can more effectively reflect pile quality information.
The present invention adopts two or more synchronous exciters on stake top, the feature that the region energy utilizing the interference wave of two row or multiple row stress wave to vibrate reinforcement is directly proportional to Amplitude-squared, the energy of the ripple of after vibration reinforced region is interfered to be far longer than single-row wave energy, make interference stresses ripple signal compared with single point excitation stress wave, effect spread can be had to obtain in communication process farther, there is the direction propagation ability that more common stress wave is stronger, compared with existing stress wave, the present invention can react a deep abnormal information better, and can guarantee detection efficiency.
The principle that the present invention adopts is: two row or the constant ripple of multiple row frequency same phase difference can interfere phenomenon in communication process, and the vibration in some region is strengthened, and the region energy that vibration is strengthened is directly proportional to Amplitude-squared; The vibration weakening in some region, and the region vibrating region and the vibration weakening strengthened is spaced from each other.
Described synchronous exciter stress wave is the identical and stress wave of constant phase difference of frequency; The present invention produces transient signal at stake top exciting, and utilizes transient state interference effect.
Second object of the present invention is realized by following technical measures: a kind of multi-point exciting device using the stress wave multi-point exciting method of above-mentioned detection pile quality, it is characterized in that: it comprises two or more impulse member, link and the support for being supported on stake top, each impulse member is connected on link, and the bottom of impulse member has jump bit, described each impulse member is regular distribution on link, described link is arranged on the top of described support, described jump bit extends on stake top through described support, so that link under external force, drive each impulse member to move downward and make jump bit impact on stake top simultaneously, realize synchronous exciter.
The present invention can make the jump bit of each impulse member impact on stake top simultaneously, thus realizes synchronous exciter; In addition, structure of the present invention is simple, be convenient for carrying, and easy to use.
As another embodiment of the invention, vertical spring is provided with between described link and described support, described link connects on the bracket by spring, to link applying active force upwards, relies on the restoring force of spring to drive each impulse member and jump bit to move downward.
As a kind of preferred embodiment of the present invention, described link and each impulse member adopt same material to make, described each impulse member is in circumferentially same, namely described each impulse member is centrosymmetric distribution, correspondingly, described link is made up of several connecting rod, and impulse member is arranged on one end of connecting rod, the other end of connecting rod collects and connects as central point, and this central point is the point of application of External Force Acting.
As one embodiment of the present invention, described support is made up of vertical pillar and the level board being fixed on pillar upper end, and the position described level board corresponding to impulse member has pilot hole, and described impulse member is passed down through pilot hole and stretches out.
As a modification of the present invention, between described impulse member and described link, be provided with the lifting regulating mechanism for regulating jump bit upper-lower position.
As one embodiment of the present invention, described lifting regulating mechanism comprises adjustment member and adjustment hole, described adjustment hole is arranged on described link and impulse member, wherein, being positioned at the adjustment hole on impulse member is provided with several along the length direction of impulse member, adjustment member is through fixing in the different adjustment hole of the adjustment hole on link and impulse member and make the height adjustable of jump bit, so that two or more jump bit can contact the different position of the corresponding depth of an end face simultaneously.
As a further improvement on the present invention, the lateral displacement governor motion for regulating impulse member position on link is provided with between described impulse member and described link.
As one embodiment of the present invention, described lateral displacement mechanism comprises adjustment member and adjustment hole, described adjustment hole is arranged on described link and impulse member, wherein, being positioned at the adjustment hole on link is provided with several along the length direction of connecting rod, adjustment member is through fixing in the different adjustment hole of the adjustment hole on impulse member and link and make the position of jump bit on link adjustable, so that different jump bits can contact shock point corresponding on stake top simultaneously.
Compared with prior art, the present invention has following significant effect:
The present invention adopts two or more synchronous exciters on stake top, the feature that the region energy utilizing the interference wave of two row or multiple row stress wave to vibrate reinforcement is directly proportional to Amplitude-squared, the energy of the ripple of after vibration reinforced region is interfered to be far longer than single-row wave energy, make interference stresses ripple signal compared with single point excitation stress wave, effect spread can be had to obtain in communication process farther, there is the direction propagation ability that more common stress wave is stronger, compared with existing stress wave, the present invention can react a deep abnormal information better, and can guarantee detection efficiency.
Accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.
Fig. 1 is the structural representation of checkout gear of the present invention.
Detailed description of the invention
Embodiment 1
A kind of stress wave multi-point exciting method detecting pile quality of the present invention, two or more synchronous exciters are adopted on stake top, produce two row or two and arrange above synchronous exciter stress waves and transient state interference in pile body, because the energy of ripple and Amplitude-squared are directly proportional, the energy of the vibration reinforced region of the interference stresses ripple after interfering is strengthened, be beneficial to interference stresses wave traveling to stake deep, to make the reflection wave signal detected strengthen compared with the reflection wave signal of single point excitation, can more effectively reflect pile quality information.
As shown in Figure 1, a kind of multi-point exciting device using the stress wave multi-point exciting method of above-mentioned detection pile quality, it comprises two impulse members 1, link 2 and the support 3 for being supported on stake top, link adopts the material of stronger rigidity to make, each impulse member 1 is vertically connected on link 2, and the bottom of impulse member 1 has jump bit 6, link 2 is positioned at the top on support 3, each impulse member 1 is regular distribution on link 2, so that link 2 under external force, drive each impulse member 1 to move downward and make jump bit 6 impact on stake top 4 simultaneously, realize synchronous exciter.
In the present embodiment, link 2 and each impulse member 1 adopt same material to make, link 2 is a connecting rod, two impulse members 1 are symmetric with the centre of connecting rod, vertical spring 5 is provided with between link 2 and support 3, link 2 is fixed on support 3 by spring 5, spring 5 is connected to the centre of connecting rod, support 3 is made up of with the level board 32 being fixed on pillar 31 upper end vertical pillar 31, position level board 32 corresponding to impulse member has pilot hole, and impulse member is passed down through pilot hole and stretches out.Link applies active force upwards, relies on the restoring force of spring to drive each impulse member to move downward and jump bit 6 is impacted on stake top.
The lifting regulating mechanism (not shown in FIG.) for regulating jump bit 6 upper-lower position is provided with between impulse member and link.Lifting regulating mechanism comprises adjustment member and adjustment hole, adjustment member is screw, adjustment hole is screw, adjustment hole is arranged on link and impulse member, wherein, being positioned at the adjustment hole on impulse member is provided with several along the length direction of impulse member, and adjustment member is through fixing in the different adjustment hole of the adjustment hole on link and impulse member and make the height adjustable of jump bit 6, so that jump bit 6 contacts the different position of the depth corresponding on stake top.
The lateral displacement governor motion (not shown in FIG.) for regulating impulse member position on link is provided with between impulse member and link.Lateral displacement mechanism comprises adjustment member and adjustment hole, adjustment member is screw, adjustment hole is screw, adjustment hole is arranged on link and impulse member, wherein, be positioned at the adjustment hole on link and be provided with several along the length direction of connecting rod, adjustment member is through fixing in the different adjustment hole of the adjustment hole on impulse member and link and make the position of impulse member on link adjustable, namely the lateral displacement of jump bit is adjustable, so that different jump bits can contact shock point corresponding on stake top simultaneously.By the adjustment of above governor motion, make two jump bit spacing, relative bearing and vertical height all adjustable.
Use procedure of the present invention is: the present invention is placed on stake top, shock point is chosen on stake top, by shock point corresponding for two jump bit contacts, and impulse member is fixed on link, upwards pull link to make spring produce potential energy, decontrol link at suitable height, at this moment, link drives jump bit to implement to impact to stake top under elastic potential energy of the spring effect, and make two jump bits synchronously to stake face exciting, two row stress waves of generation interfere in pile body.
Embodiment 2
The present embodiment is with the difference of embodiment 1: be not directly connected between link and support, link is bearing on stake top by impulse member, applies downward active force to link, drives each impulse member to move downward, jump bit is impacted on stake top simultaneously, realizes synchronous exciter.Each impulse member is in circumferentially same, and namely each impulse member is centrosymmetric distribution, correspondingly, link is made up of several connecting rod, impulse member is arranged on one end of connecting rod, and the other end of connecting rod collects and connects as central point, and this central point is the point of application of External Force Acting.
Use procedure of the present invention is: the present invention is placed on stake top, shock point is chosen on stake top, by shock point corresponding for two jump bit contacts, and impulse member is fixed on link, firmly hammer the middle part of striking link into shape and make each jump bit synchronously to stake face exciting, each row stress wave of generation interferes in pile body.
Embodiments of the present invention are not limited thereto; according to foregoing of the present invention; according to ordinary technical knowledge and the customary means of this area; do not departing under the present invention's above-mentioned fundamental technics thought prerequisite; the structure of the link of multi-point exciting device of the present invention, support, impulse member also has other embodiment; therefore the present invention can also make the amendment of other various ways, replacement or change, all drops within rights protection scope of the present invention.