A concrete pouring homogeneity intelligent detection system and method

Abstract

The present invention relates to an intelligent detection system and method for concrete pouring homogeneity, which comprises a mobile suspension frame, a free mechanical arm, a multifunctional composite detector and a data processing center. The mobile suspension frame comprises a mobile triangular bracket and a horizontal beam. The mobile triangular bracket is symmetrically mounted on templates on both sides, and a roller is arranged at the bottom end thereof; the horizontal beam is provided with a longitudinal through hole; the free mechanical arm is mounted on the horizontal beam through the through hole, and a pushing component of the free mechanical arm is fixed on the horizontal beam, the upper end of the push rod is connected to the pushing component, and the lower end is connected to a material collector; the multifunctional composite detector is mounted on the mobile triangular bracket, and comprises a material receiver, a weighing system, a screening device and a mobile component, the weighing system is arranged at the bottom of the side wall of the material receiver, the screening device comprises an attached vibration motor and a shock absorbing device, the attached vibration motor is arranged on the side wall of the material receiver, and the shock absorbing device is used to connect the mobile component and the weighing system.

Description

Technical Field

[0001] The invention belongs to the technical field of concrete, and in particular relates to an intelligent detection system and method for concrete pouring homogeneity. Background Art

[0002] Concrete is the largest bulk material in construction projects. The detection and control of homogeneity during pouring construction will directly affect the quality and safety of concrete structures and is of vital importance in engineering construction.

[0003] At present, concrete homogeneity testing is mainly reflected in two aspects: on the one hand, it is mainly concentrated in concrete mixing stations. Such testing methods mainly include visual inspection, slump test, humidity measurement, water resistance measurement, sieve analysis, dielectric constant measurement, etc. These methods can effectively evaluate the homogeneity of concrete preparation, and make homogeneity control decisions such as mix ratio adjustment and preparation process innovation based on this to ensure the quality of commercial concrete. However, such methods belong to pre-testing and cannot guarantee the homogeneity requirements of concrete during the pouring construction stage. On the other hand, it is mainly concentrated on the construction site. The test object is the formed concrete structure. Such testing methods mainly include visual inspection, ultrasonic testing, drilling sampling, etc. However, such methods belong to post-testing. Once the homogeneity does not meet the requirements, the only way is to take the method of breaking down and rebuilding. Otherwise, the fact that the formed concrete structure is inhomogeneous cannot be changed, which is likely to have an adverse impact on the quality, safety, progress and cost control of the project construction.

[0004] Therefore, how to provide an intelligent detection system and method for concrete pouring homogeneity to provide powerful technical guidance for adjusting concrete pouring and vibration construction methods and ensure the quality of concrete construction is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] The present invention provides an intelligent detection system and method for concrete pouring homogeneity, which adopts a concrete pouring homogeneity determination rule based on a standard concrete quality deviation rate and a standard aggregate volume fraction deviation rate, and combines the innovative structural design of the intelligent detection system to effectively solve the problem of real-time, accurate, efficient and scientific evaluation of concrete pouring homogeneity at the construction site, provide powerful technical guidance for on-site real-time adjustment of concrete pouring and vibration construction methods, and ensure the concrete construction quality and structural safety.

[0006] In order to solve the above technical problems, the present invention includes the following technical solutions:

[0007] An intelligent detection system for concrete pouring homogeneity, comprising:

[0008] A mobile suspension frame, the mobile suspension frame comprises a mobile triangular bracket and a horizontal beam, the mobile triangular bracket is symmetrically mounted on the templates on both sides, and the mobile triangular bracket moves forward and backward on the top of the template through the bottom roller; the horizontal beam is fixedly arranged on the mobile triangular bracket, and a longitudinal through hole is provided on the horizontal beam;

[0009] A free mechanical arm, the free mechanical arm is mounted on the horizontal beam through the through hole and can move along the length direction of the horizontal beam, the free mechanical arm comprises a push rod, a material picker and a push component, the push component is fixed on the horizontal beam, the upper end of the push rod is connected to the push component, and the lower end of the push rod is connected to the material picker;

[0010] A multifunctional composite detector, the multifunctional composite detector is mounted on the mobile tripod support, the multifunctional composite detector includes a material receiver, a weighing system, a screening device and a moving part, the weighing system is arranged at the bottom of the side wall of the material receiver, the weighing system includes a wireless gravity sensor and a power supply device, the screening device includes an attached vibration motor and a shock absorbing device, the attached vibration motor is arranged on the side wall of the material receiver, and the shock absorbing device is used to connect the moving part and the weighing system;

[0011] A data processing center is used to receive data information sent by the multifunctional composite detector in real time and process and analyze the data.

[0012] Furthermore, the material picker includes an upper movable cover plate, a movable door and a side panel. The upper movable cover plate is located above the material picker and is connected to the push rod on the same side through an upper buckle. The upper movable cover plate has two working states: horizontal and buckled. The upper end of the movable door is connected to the upper movable cover plate through a hinge, and the lower end of the movable door is connected to the push rod on the same side through a lower buckle, and has two working states: closed and open. The side panel side wall is connected to the movable door, and the upper end of the side panel is connected to the upper movable cover plate.

[0013] Furthermore, the bottom of the receiver is a double-layer design, the upper layer is a metal screen, and the lower layer is a free opening and closing bottom plate, and the aperture of the metal screen is smaller than the minimum particle size of concrete coarse aggregate.

[0014] Furthermore, the material receiver is a cylindrical steel barrel.

[0015] The present invention also provides a method for intelligent detection of concrete pouring homogeneity, which comprises the following steps:

[0016] Step S1, providing the concrete pouring homogeneity intelligent detection system for standby;

[0017] Step S2: Select N concrete homogeneity detection points (x, y, and z) with different lengths, widths, and heights at different locations inside the concrete structure. i ,y i ,z i ), i=1~N, and input the coordinates of the detection points into the data processing center; at the same time, input the mass m0 of 1.0L standard homogeneous concrete and its aggregate volume fraction w0 measured in the laboratory into the data processing center;

[0018] Step S3, erecting a mobile suspension frame above the concrete formwork, installing a free mechanical arm on the horizontal beam, and installing a multifunctional composite detector on the mobile tripod bracket;

[0019] Step S4, continuously pouring the concrete mixture into the cavity enclosed by the template;

[0020] Step S5: Move the push rod along the length direction of the through hole so that the material picker is located at the detection point x. i Position, move the mobile tripod forward and backward to make the material picker located at the detection point y i Position, push the push rod up and down to insert the material picker into the concrete until it is at the detection point z i Position, during this process, the upper movable cover of the material picker is always in a horizontal state;

[0021] Step S6, opening the upper buckle to allow the concrete to flow into the material dispensing device, and pressing the upper movable cover plate onto the movable door in the closed state;

[0022] Step S7, lift up and move the push rod to the right until the material taker is placed directly above the material receiver;

[0023] Step S8, open the lower buckle to open the movable door, let the concrete flow into the receiver, smooth the upper surface of the receiver, and ensure that the volume of concrete in the receiver is 1.0L;

[0024] Step S9: Start the weighing system and weigh the mass of concrete in the receiver as m. i , turn off the weighing system;

[0025] Step S10, through the controller, open the free opening and closing bottom plate of the material receiver, start the attached vibration motor, screen the concrete mixture in the material receiver through the metal screen, until there is no slurry remaining in the material receiver, and turn off the attached vibration motor;

[0026] Step S11: Start the weighing system to weigh the mass m of the concrete coarse aggregate in the receiver. 粗 , turn off the weighing system;

[0027] Step S12: In the data processing center, i =m粗 ×1000×100% / ρ / 1.0, the volume fraction w of concrete aggregate in the receiver is calculated i , m 粗 is the mass of coarse aggregate remaining in the receiver after the concrete sample at the detection point is sieved to remove the cement paste, the unit is Kg; ρ is the density of coarse aggregate in concrete, the unit is Kg / m 3 , 1000 is m 3 The conversion factor for converting units to L units is 1.0, which is the volume of concrete in the receiver, i.e. the volume of the receiver, in L;

[0028] Step S13: Calculate the standard concrete quality deviation rate Q m =(m i -m0)×100% / m0; calculate the standard aggregate volume fraction deviation rate Q w =(w i -w0)×100% / w0;

[0029] Step S14, evaluating the concrete pouring homogeneity according to the concrete pouring homogeneity determination rule;

[0030] Step S15, repeat the above steps S5 to S14 to complete the intelligent detection of concrete homogeneity at all detection points.

[0031] Furthermore, the concrete pouring homogeneity determination rule in step 14 includes:

[0032] 1) If -3%≤Q m ≤3%, -2.5%≤Q w ≤2.5%, it indicates that the concrete pouring homogeneity is better;

[0033] 2) If Q m >3%, Q w >2.5%, it indicates that the internal homogeneity of the poured concrete is poor, the coarse aggregate is agglomerated, and the mortar is insufficient;

[0034] 3) If Q m <-3%, Q w <-2.5%, it indicates that the internal homogeneity of the poured concrete is poor, the coarse aggregate is insufficient, and there is more mortar.

[0035] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] The present invention provides a concrete pouring homogeneity intelligent detection system and method, which can implement fully automatic on-site intelligent sampling and analysis of concrete mixtures poured on site, obtain cast-in-place concrete mixtures and coarse aggregate samples in different structural parts, and adopt concrete pouring homogeneity determination rules based on standard concrete mass deviation rate and standard aggregate volume fraction deviation rate to meet the real-time, accurate, efficient and scientific evaluation needs of concrete pouring homogeneity at the construction site, provide powerful technical guidance for the adjustment of concrete pouring and vibration construction methods, and ensure the quality of concrete construction and structural safety. Moreover, the concrete pouring homogeneity intelligent detection system and method are generally applicable to various concrete structure pouring scenes such as frames, columns, slabs, beams, etc., and are particularly applicable to concrete pouring scenes in special structural parts such as steel bar-intensive areas, meeting the evaluation needs of concrete pouring homogeneity at the construction site. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a structural schematic diagram of an intelligent detection system for concrete pouring homogeneity according to an embodiment of the present invention;

[0038] Figure 2 This is a structural schematic diagram of a free mechanical arm taking materials in an intelligent detection system for concrete pouring homogeneity according to an embodiment of the present invention;

[0039] Figure 3 This is a structural schematic diagram of a free mechanical arm discharging material in an intelligent detection system for concrete pouring homogeneity according to an embodiment of the present invention;

[0040] Figure 4 It is a schematic diagram of the structure of a multifunctional composite detector in an intelligent detection system for concrete pouring homogeneity according to an embodiment of the present invention.

[0041] In the figure:

[0042] 10-mobile hanging frame, 11-mobile tripod, 12-horizontal beam, 13-template; 20-free mechanical arm, 21-push rod, 22-feeder, 23-pushing component, 24-upper movable cover, 25-movable door, 26-side panel, 27-upper buckle, 28-lower buckle, 29-hinge; 30-multifunctional composite detector, 31-feeder, 32-moving component, 33-wireless gravity sensor, 34-power supply equipment, 35-attached vibration motor, 36-shock absorption equipment, 37-metal screen, 38-free opening and closing bottom plate, 39-controller; 40-data processing center; 50-concrete. DETAILED DESCRIPTION

[0043] The following is a further detailed description of a concrete pouring homogeneity intelligent detection system and method provided by the present invention in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will become clearer. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. For the convenience of description, the "upper" and "lower" described below are consistent with the upper and lower directions of the accompanying drawings, but this cannot be a limitation of the technical solution of the present invention. Embodiment 1

[0044] Combine the following Figures 1 to 4 , and detailedly explains the structural composition of the intelligent detection system for concrete pouring homogeneity.

[0045] Please refer to Figures 1 to 4 , a concrete pouring homogeneity intelligent detection system, including a movable suspension frame 10, a free mechanical arm 20, a multifunctional composite detector 30 and a data processing center 40.

[0046] The mobile suspension frame 10 includes a mobile triangular bracket 11 and a horizontal beam 12. The mobile triangular bracket 11 is symmetrically mounted on the templates 13 on both sides. The mobile triangular bracket 11 moves forward and backward on the top of the template 13 through the bottom rollers; the horizontal beam 12 is fixedly arranged on the mobile triangular bracket 11, and a longitudinal through hole is provided on the horizontal beam 12.

[0047] The free manipulator 20 is mounted on the horizontal beam 12 through the through hole and can move along the length direction of the horizontal beam 12. The free manipulator 20 includes a push rod 21, a material picker 22 and a push component 23. The push component 23 is fixed on the horizontal beam 12. The upper end of the push rod 21 is connected to the push component 23, and the lower end of the push rod 21 is connected to the material picker 22. The push component 23 provides power for the push rod 21 to take materials up and down. The material picker 22 has a volume of 1.2L and is used to take concrete 50 poured on site at a fixed point.

[0048] The multifunctional composite detector 30 is mounted on the mobile tripod support 11. The multifunctional composite detector 30 includes a material receiver 31, a weighing system, a screening device, and a moving part 32. The weighing system is arranged at the bottom of the side wall of the material receiver 31. The weighing system includes a wireless gravity sensor 33 and a power supply device 34. The screening device includes an attached vibration motor 35 and a shock absorbing device 36. The attached vibration motor 35 is arranged on the side wall of the material receiver 31. The shock absorbing device 36 is used to connect the moving part 32 and the weighing system. The weighing system is used to weigh the quality of concrete or aggregate in the material receiver 31 and send the data to the data processing center 40.

[0049] The data processing center 40 is used to receive the data information sent by the multifunctional composite detector 30 in real time, and process and analyze the data, so as to scientifically and accurately evaluate the pouring homogeneity of concrete and guide the construction.

[0050] In this embodiment, more preferably, the material picker 22 includes an upper movable cover plate 24, a movable door 25 and a side panel 26. The upper movable cover plate 24 is located above the material picker 22 and is connected to the push rod 21 on the same side through an upper buckle 27. The upper movable cover plate 24 has two working states: horizontal and buckled; the upper end of the movable door 25 is connected to the upper movable cover plate 24 through a hinge 29, and the lower end of the movable door 25 is connected to the push rod 21 on the same side through a lower buckle 28, and has two working states: closed and open; the side wall of the side panel 26 is connected to the movable door 25, and the upper end of the side panel 26 is connected to the upper movable cover plate 24.

[0051] In this embodiment, more preferably, the bottom of the receiver 31 is a double-layer design, the upper layer is a metal screen 37, and the lower layer is a free opening and closing bottom plate 38, and the aperture of the metal screen 37 is smaller than the minimum particle size of the concrete coarse aggregate.

[0052] In this embodiment, more preferably, the receiver 31 is a cylindrical steel barrel, and the volume of the receiver 31 is 1.0L.

[0053] Please continue to refer to Figures 1 to 4 This embodiment also provides a method for intelligent detection of concrete pouring homogeneity, which includes the following steps:

[0054] Step S1, providing the concrete pouring homogeneity intelligent detection system for standby;

[0055] Step S2: Select N concrete homogeneity detection points (x, y, and z) with different lengths, widths, and heights at different locations inside the concrete structure. i ,y i ,z i ), i=1~N, and input the coordinates of the detection points into the data processing center; at the same time, input the mass m0 of 1.0L standard homogeneous concrete and its aggregate volume fraction w0 measured in the laboratory into the data processing center 40;

[0056] Step S3, erecting a mobile suspension frame 10 above the concrete formwork 13, installing a free mechanical arm 20 on the horizontal beam 12, and installing a multifunctional composite detector 30 on the mobile tripod bracket 11;

[0057] Step S4, continuously pouring a concrete mixture 50 into the cavity enclosed by the template 13;

[0058] Step S5: Move the push rod 21 along the length direction of the through hole so that the material picker 22 is located at the detection point x. iPosition, move the mobile tripod support 11 forward and backward, so that the material picker 22 is located at the detection point y i The push rod 21 is pushed up and down to insert the material picker 22 into the concrete 50 until it is located at the detection point z. i Position, during which the upper movable cover plate 24 of the material picker 22 is always in a horizontal state;

[0059] Step S6, opening the upper buckle 27 to allow the concrete 50 to flow into the material extractor 22, and pressing the upper movable cover plate 24 onto the movable door 25 in the closed state;

[0060] Step S7, lift up and move the push rod 21 to the right until the material taker 22 is placed directly above the material receiver 31;

[0061] Step S8, open the lower buckle 28, so that the movable door 25 is in an open state, the concrete 50 flows into the inside of the receiver 31, and the upper surface of the receiver 31 is smoothed to ensure that the volume of the concrete 50 in the receiver 31 is 1.0L;

[0062] Step S9: Start the weighing system to weigh the mass of the concrete 50 in the receiver 31 as m i , turn off the weighing system;

[0063] Step S10, through the controller 39, the free opening and closing bottom plate 38 of the material receiver 31 is opened, the attached vibration motor 35 is started, and the concrete mixture in the material receiver 31 is screened through the metal screen 37 until there is no slurry remaining in the material receiver 31, and the attached vibration motor 35 is turned off;

[0064] Step S11, start the weighing system to weigh the mass m of the concrete coarse aggregate in the receiver 31 粗 , turn off the weighing system;

[0065] Step S12: In the data processing center 40, by w i =m 粗 ×1000×100% / ρ / 1.0, the concrete aggregate volume fraction w in the receiver 31 is calculated i , m 粗 is the mass of coarse aggregate remaining in the receiver after the concrete sample at the detection point is sieved to remove the cement paste, the unit is Kg; ρ is the density of coarse aggregate in concrete, the unit is Kg / m 3 , 1000 is m 3 The conversion factor for converting units to L units is 1.0, which is the volume of concrete in the receiver, i.e. the volume of the receiver, in L;

[0066] Step S13: Calculate the standard concrete quality deviation rate Q m =(m i-m0)×100% / m0; calculate the standard aggregate volume fraction deviation rate Q w =(w i -w0)×100% / w0;

[0067] Step S14, evaluating the concrete pouring homogeneity according to the concrete pouring homogeneity determination rule;

[0068] Step S15, repeat the above steps S5 to S14 to complete the intelligent detection of concrete homogeneity at all detection points.

[0069] In this embodiment, more preferably, the concrete pouring homogeneity determination rule in step 14 includes:

[0070] 1) If -3%≤Q m ≤3%, -2.5%≤Q w ≤2.5%, it indicates that the concrete pouring homogeneity is better;

[0071] 2) If Q m >3%, Q w >2.5%, it indicates that the internal homogeneity of the poured concrete is poor, the coarse aggregate is agglomerated, and the mortar is insufficient;

[0072] 3) If Q m <-3%, Q w <-2.5%, it indicates that the internal homogeneity of the poured concrete is poor, the coarse aggregate is insufficient, and there is more mortar.

[0073] The above examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. The above embodiments only express several embodiments of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An intelligent detection system for concrete pouring homogeneity, characterized in that: include: A mobile suspension frame, the mobile suspension frame comprises a mobile triangular bracket and a horizontal beam, the mobile triangular bracket is symmetrically mounted on the templates on both sides, and the mobile triangular bracket moves forward and backward on the top of the template through the bottom roller; the horizontal beam is fixedly arranged on the mobile triangular bracket, and a longitudinal through hole is provided on the horizontal beam; A free mechanical arm, the free mechanical arm is mounted on the horizontal beam through the through hole and can move along the length direction of the horizontal beam, the free mechanical arm comprises a push rod, a material picker and a push component, the push component is fixed on the horizontal beam, the upper end of the push rod is connected to the push component, and the lower end of the push rod is connected to the material picker; A multifunctional composite detector, the multifunctional composite detector is mounted on the mobile tripod support, the multifunctional composite detector includes a material receiver, a weighing system, a screening device and a moving part, the weighing system is arranged at the bottom of the side wall of the material receiver, the weighing system includes a wireless gravity sensor and a power supply device, the screening device includes an attached vibration motor and a shock absorbing device, the attached vibration motor is arranged on the side wall of the material receiver, and the shock absorbing device is used to connect the moving part and the weighing system; A data processing center, the data processing center is used to receive the data information sent by the multifunctional composite detector in real time and process and analyze the data; The material extractor comprises an upper movable cover plate, a movable door and a side plate. The upper movable cover plate is located above the material extractor and is connected to the push rod on the same side through an upper buckle. The upper movable cover plate has two working states: horizontal and buckled. The upper end of the movable door is connected to the upper movable cover plate through a hinge, and the lower end of the movable door is connected to the push rod on the same side through a lower buckle, and has two working states: closed and open. The side wall of the side plate is connected to the movable door, and the upper end of the side plate is connected to the upper movable cover plate. The bottom of the receiver is a double-layer design, the upper layer is a metal screen, and the lower layer is a free opening and closing bottom plate. The aperture of the metal screen is smaller than the minimum particle size of the concrete coarse aggregate.

2. The intelligent detection system for concrete pouring homogeneity according to claim 1 is characterized in that: The material receiver is a cylindrical steel barrel.

3. A method for intelligent detection of concrete pouring homogeneity, characterized in that: The steps include: Step S1, providing the intelligent detection system for concrete pouring homogeneity according to claim 1 or 2 for standby; Step S2: Select N concrete homogeneity detection points (x, y, and z) with different lengths, widths, and heights at different locations inside the concrete structure. i ,y i ,z i ), i=1~N, and input the coordinates of the detection points into the data processing center; At the same time, the mass m0 of 1.0L standard homogeneous concrete and its aggregate volume fraction w0 measured in the laboratory are input into the data processing center; Step S3, erecting a mobile suspension frame above the concrete formwork, installing a free mechanical arm on the horizontal beam, and installing a multifunctional composite detector on the mobile tripod bracket; Step S4, continuously pouring the concrete mixture into the cavity enclosed by the template; Step S5: Move the push rod along the length direction of the through hole so that the material picker is located at the detection point x. i Position, move the mobile tripod forward and backward to make the material picker located at the detection point y i Position, push the push rod up and down to insert the material picker into the concrete until it is at the detection point z i Position, during this process, the upper movable cover of the material picker is always in a horizontal state; Step S6, opening the upper buckle to allow the concrete to flow into the material dispensing device, and pressing the upper movable cover plate onto the movable door in the closed state; Step S7, lift up and move the push rod to the right until the material taker is placed directly above the material receiver; Step S8, open the lower buckle to open the movable door, let the concrete flow into the receiver, smooth the upper surface of the receiver, and ensure that the volume of concrete in the receiver is 1.0L; Step S9: Start the weighing system and weigh the mass of concrete in the receiver as m. i , turn off the weighing system; Step S10, through the controller, open the free opening and closing bottom plate of the material receiver, start the attached vibration motor, screen the concrete mixture in the material receiver through the metal screen, until there is no slurry remaining in the material receiver, and turn off the attached vibration motor; Step S11: Start the weighing system to weigh the mass m of the concrete coarse aggregate in the receiver. 粗 , turn off the weighing system; Step S12: In the data processing center, i =m 粗 ×1000×100% / ρ / 1.0, the volume fraction w of concrete aggregate in the receiver is calculated i ;m 粗 is the mass of coarse aggregate remaining in the receiver after the concrete sample at the detection point is sieved to remove the cement paste, the unit is Kg; ρ is the density of coarse aggregate in concrete, the unit is Kg / m 3 , 1000 is m 3 The conversion factor for converting units to L units is 1.0, which is the volume of concrete in the receiver in L; Step S13: Calculate the standard concrete quality deviation rate Q m =(m i -m0)×100% / m0; calculate the standard aggregate volume fraction deviation rate Q w =(w i -w0)×100% / w0; Step S14, evaluating the concrete pouring homogeneity according to the concrete pouring homogeneity determination rule; Step S15, repeat the above steps S5 to S14 to complete the intelligent detection of concrete homogeneity at all detection points.

4. The method according to claim 3, characterized in that The concrete pouring homogeneity determination rule in step 14 includes: 1) If -3%≤Q m ≤3%, -2.5%≤Q w ≤2.5%, it indicates that the concrete pouring homogeneity is better; 2) If Q m >3%, Q w >2.5%, it indicates that the internal homogeneity of the poured concrete is poor, the coarse aggregate is agglomerated, and the mortar is insufficient; 3) If Q m <-3%, Q w <-2.5%, it indicates that the internal homogeneity of the poured concrete is poor, the coarse aggregate is insufficient, and there is more mortar.

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