CN111300619A - Automatic temperature control system of prefabricated box girder steam health preserving - Google Patents
Automatic temperature control system of prefabricated box girder steam health preserving Download PDFInfo
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- CN111300619A CN111300619A CN202010239935.0A CN202010239935A CN111300619A CN 111300619 A CN111300619 A CN 111300619A CN 202010239935 A CN202010239935 A CN 202010239935A CN 111300619 A CN111300619 A CN 111300619A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
- B28B11/24—Apparatus or processes for treating or working the shaped or preshaped articles for curing, setting or hardening
- B28B11/245—Curing concrete articles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
- B28B11/24—Apparatus or processes for treating or working the shaped or preshaped articles for curing, setting or hardening
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B17/00—Details of, or accessories for, apparatus for shaping the material; Auxiliary measures taken in connection with such shaping
- B28B17/0063—Control arrangements
- B28B17/0081—Process control
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D23/00—Control of temperature
- G05D23/19—Control of temperature characterised by the use of electric means
- G05D23/20—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Mechanical Engineering (AREA)
- Structural Engineering (AREA)
- Automation & Control Theory (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
- On-Site Construction Work That Accompanies The Preparation And Application Of Concrete (AREA)
Abstract
The invention discloses a steam curing automatic temperature control system for a prefabricated box girder, and relates to the technical field of concrete curing. The automatic temperature control system for steam curing of the prefabricated box girder comprises a control host (an upper computer), a PLC host (a lower computer), a temperature control module, a temperature sensor, an electromagnetic valve, a ventilator and the like. The control host (upper computer) can be connected with a plurality of (expandable) PLC hosts, and each PLC host (lower computer) is connected with four temperature sensors to respectively measure the temperatures of the top, the bottom, the outside and the inside of the concrete box girder. The automatic temperature control system for steam curing of the prefabricated box girder has the advantages of being high in precision, strong in controllability and automatic. The invention provides a set of perfect automatic temperature control system aiming at the problems of simple and crude equipment, extensive temperature control and the like in construction, so that the steam curing process of concrete is more mature, complete and reliable.
Description
Technical Field
The invention relates to the technical field of concrete curing, in particular to a steam curing automatic temperature control system for a prefabricated box girder.
Background
At present, the research of China in the field of large-volume concrete temperature control is not deep and comprehensive enough, relevant standard provisions are not perfect enough, and many problems in engineering practice only depend on experience and lack of theoretical basis. The large-volume concrete generally has problems in that cracks are generated due to temperature change, so that the anti-permeability, anti-cracking and anti-corrosion properties of the concrete are reduced, and the durability of the whole structure is affected. The concrete box girder belongs to the mass concrete building, so that the concrete is effectively monitored and controlled in temperature, the temperature change rule of the concrete box girder and the influence of various materials on the temperature under different conditions are better mastered, and how to improve the durability of the concrete box girder structure becomes an important problem which needs to be solved urgently by engineering technicians.
The cast-in-place concrete has large geometric dimension, and technical measures must be adopted to avoid cracks caused by cement hydration heat and volume change, and the structure is called as large-volume concrete. In the construction of large-volume concrete foundations at home and abroad, a steam curing temperature control system for a concrete box girder, which is adopted for preventing cracks, is one of effective ways for solving the problems.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides an automatic temperature control system for steam curing of a precast box girder, which solves the problems that the existing steam curing equipment is simple and crude, the precision is low, the temperature control mainly depends on manual intermittent measurement and adjustment, the effectiveness and the precision of temperature control in each stage of steam curing are difficult to ensure, particularly the temperature rising rate and the temperature reduction rate are difficult to control, and the wide application of the technology is seriously limited.
(II) technical scheme
In order to achieve the purpose, the invention is realized by the following technical scheme: a prefabricated box girder steam health-preserving automatic temperature control system comprises a control host (an upper computer), a PLC host (a lower computer), a temperature module, a temperature sensor, an electromagnetic valve and a ventilator, wherein the temperature module collects temperature on site through the temperature sensor, the temperature sensor converts measured temperature (analog signals) into numerical quantity signals which can be identified by a PLC master through A/D conversion, and the converted numerical quantity signals are stored in a certain data storage area of the PLC host so as to be inquired by the control host (the upper computer) at any time;
steam curing parameters (the time and the temperature of a pre-curing period, the heating speed of a heating period, the constant temperature time and the constant temperature of the heating period and the constant temperature and the cooling speed of a cooling period) of the position where the temperature sensor is located are set by a control host (an upper computer);
the parameter value sent by the control host (upper computer) is higher than the temperature value acquired by the temperature sensor from the field, the PLC host (lower computer) can start electromagnetism to open steam, and meanwhile, the ventilator is ensured to be closed, so that the temperature of the concrete box girder can gradually rise until the required temperature is reached;
and if the parameter value sent by the control host (upper computer) is lower than the temperature value acquired by the temperature sensor from the field, the PLC host (lower computer) closes the electromagnetic valve to stop the steam from being turned on and turns on the ventilator at the same time.
Preferably, the PLC host (lower computer) controls the opening and closing of the electromagnetic valve according to the parameter value sent by the control host (upper computer) and the temperature value acquired by the temperature sensor to realize the on-off of the steam supply, and the starting and the opening of the ventilator are directly controlled by the PLC host (lower computer).
Preferably, the automatic temperature control system for steam curing of the precast box girder is characterized in that an industrial control computer of a control host (an upper computer) is mainly used for an industrial real-time measurement and control system, a DVP series programmable controller SS modular standard functional host DVP14SS11R2 of a Taida is selected as the PLC host (a lower computer), a host power supply is DC24V, four temperature sensors are connected to the temperature modules and each PLC (the lower computer), and the temperature sensors are platinum temperature sensors (PT1003 line 100 omega 3850PPM/° C).
(III) advantageous effects
The invention provides a steam curing automatic temperature control system for a prefabricated box girder. The method has the following beneficial effects:
this automatic temperature control system of precast box girder steam health preserving, through using with roof beam steam health preserving device cooperation, ensure that newly-poured concrete is high at a certain time internal precision, the controllability is strong and the hardening in the temperature environment under the automatic characteristics, prevent effectively that the concrete from drying and splitting early, guarantee concrete later stage intensity and durability, its operating method is simple, easy operation, safe and reliable controls the temperature maintenance effectually simultaneously.
Drawings
FIG. 1 is a schematic diagram of the temperature control of the present invention;
FIG. 2 is a diagram of a PLC standard function host and an extended configuration according to the present invention;
FIG. 3 is a diagram of the PLC installation dimensions of the present invention;
FIG. 4 is a connection diagram of the control host and the PLC according to the present invention;
FIG. 5 is a flowchart of a temperature control procedure according to the present invention.
In the figure: 1. a control host; 2. a PLC host; 3. a temperature module; 4. a temperature sensor; 5. an electromagnetic valve; 6. a ventilator; 21. 1# PLC host; 22. 2# PLC host; 23. 3# PLC host; 24. 4# PLC host.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, the present invention provides a technical solution: the utility model provides a prefabricated box girder steam health preserving automation temperature control system, includes that temperature module 3 passes through temperature sensor 4 and gathers the temperature at the scene, then converts the numerical value signal that PLC host computer 2 can discern into temperature (analog signal) that record through the AD conversion to the numerical value signal after the conversion has a certain data storage area of PLC host computer 2, inquires at any time in order to be prepared for control host computer (host computer) 1. Steam-curing parameters (time and temperature of a pre-curing period, heating speed of a heating period, heating time, constant-temperature time and constant-temperature of a constant-temperature period, cooling speed of a cooling period and the like) of positions measured by the temperature sensors 4 are set by a control host (upper computer) 1. If the parameter value sent by the control host (upper computer) 1 is higher than the temperature value collected by the temperature sensor 4 from the field, the PLC host (lower computer) 2 can open the electromagnetic valve 5 to open the steam, and simultaneously ensures that the ventilator 6 is closed, so that the temperature of the concrete box girder can gradually rise until the required temperature is reached. If the parameter value sent by the control host (upper computer) 1 is lower than the temperature value acquired by the temperature sensor 4 from the field, the PLC host (lower computer) 2 closes the electromagnetic valve 5 to stop the steam from being turned on, and simultaneously turns on the ventilator 6.
The PLC host (lower computer) 2 controls the opening and closing of the electromagnetic valve 5 according to the parameter value sent by the control host (upper computer) 1 and the temperature value collected by the temperature sensor 4 to realize the on-off of the supplied steam, and the starting and the opening of the ventilator 6 are directly controlled by the PLC host (lower computer) 2.
Referring to fig. 2-4, the industrial control computer of the control host (upper computer) 1 is mainly used for an industrial real-time measurement and control system, and has different characteristics from a general computer. The PLC host (lower computer) 2 selects a DVP series programmable controller SS modular standard functional host DVP14SS11R2 of the Taida, and the power supply of the host is DC 24V. The temperature module 3, each DVP04PT-S temperature module 3 is connected with four temperature sensors 4PT 100, and the PT100 uses 3-wire temperature sensors 4. A # 1 PLC host 21, a # 2 PLC host 22; the 3# PLC host 23 and the 4# PLC host 24 are connected with four temperature sensors 4 respectively through each PLC (lower computer) 2. The temperature sensor 4 is a platinum temperature sensor (PT1003 line 100 omega 3850 PPM/DEG C).
Referring to fig. 5, after the concrete box girder starts to be cured by combining with the steam curing device, the temperature data of the site is measured by the thermal resistance temperature sensor 4, converted into digital quantity by the temperature module 3 and stored in the storage area of the temperature module 3, and the PLC host 2 reads the numerical value of the temperature module 3 by the FROM command and transmits the numerical value to the industrial control computer (upper computer) 1 by the data signal line; the industrial control computer (upper computer) 1 sends the set parameters of each stage of steam curing to the lower computer, and the lower computer adjusts the control algorithm according to the parameter values sent by the upper computer and sends out the control quantity. In order to realize the continuous adjustability control of the temperature control, a PID controller adjusting mode is adopted, a speed parameter value is preset, and the PID controller adjusts and automatically follows the set speed value. The steam curing device is combined, so that the concrete of the whole beam body is continuously wetted, and the curing effects of heat preservation, moisture preservation and temperature control are achieved.
During operation, the temperature control in the whole steam curing process is divided into six stages: a pre-curing stage, a temperature rise I stage, an intermediate rest stage, a temperature rise II stage, a constant temperature stage and a temperature reduction stage. The temperature sensors 4 measure the temperature values of four points of the upper part, the lower part, the inner part and the outer part of the concrete box girder, an electromagnetic valve 5 is arranged near each temperature measuring point to control the supply and the stop of steam, and the whole control system is provided with a ventilator 6 for cooling.
In conclusion, the automatic temperature control system for steam curing of the precast box girder ensures that newly poured concrete is hardened in a temperature environment with the characteristics of high precision, strong controllability and automation within a certain time through being matched with the girder steam curing device, effectively prevents early-stage dry cracking of the concrete, ensures later-stage strength and durability of the concrete, and has the advantages of simple operation method, easy operation, safety, reliability and good temperature control curing effect.
The device can provide the technical measure for the great concrete box girder of geometric dimension and avoid the crack that cement hydration heat and volume change arouse, concrete surface's heat preservation, it is effectual to keep moist maintenance, avoid appearing the dry and wet circulation, prevent that box girder concrete surface from forming phenomenons such as crack, the device is easy to be operated moreover, safe and reliable, repeatedly usable, the installation, it is convenient to dismantle, it is energy-saving to save labour, save the water source, both guarantee concrete health preserving effect, can improve the inherent quality of concrete again, guarantee concrete later stage intensity and durability.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (3)
1. The utility model provides an automatic temperature control system of prefabricated box girder steam health preserving, includes main control system (host computer) (1), PLC host computer (lower computer) (2), temperature module (3), temperature sensor (4), solenoid valve (5) and ventilation blower (6), its characterized in that: the temperature module (3) collects temperature on site through a temperature sensor (4), the temperature sensor (4) converts measured temperature (analog signal) into a numerical quantity signal which can be identified by the PLC host (2) through A/D conversion, and the converted numerical quantity signal is stored in a certain data storage area of the PLC host (2) for the control host (upper computer) (1) to inquire at any time;
steam curing parameters (the time and the temperature of a pre-curing period, the heating speed of a heating period, the constant temperature time and the constant temperature of a heating period and the cooling speed of a cooling period) of the position measured by the temperature sensor (4) are set by a control host (an upper computer) (1);
the parameter value sent by the control host (upper computer) (1) is higher than the temperature value acquired by the temperature sensor (4) from the field, the PLC host (lower computer) (2) can open the electromagnetic valve (5) to open the steam, and simultaneously ensures that the ventilator (6) is closed, so that the temperature of the concrete box girder can gradually rise until the required temperature is reached;
the parameter value that control host computer (host computer) (1) sent is less than the temperature value that temperature sensor (4) gathered from the scene, then PLC host computer (host computer) (2) can close solenoid valve (5) and make steam stop opening, and open ventilation blower (6) simultaneously.
2. The automatic steam curing temperature control system for the precast box girder according to claim 1, is characterized in that: the PLC host (lower computer) (2) controls the opening and closing of the electromagnetic valve (5) to realize the on-off of the supplied steam according to the parameter value sent by the control host (upper computer) (1) and the temperature value collected by the temperature sensor (4), and the starting and the opening of the ventilator (6) are directly controlled by the PLC host (lower computer) (2).
3. The automatic steam curing temperature control system for the precast box girder according to claim 1, is characterized in that: the control host (upper computer) (1) industrial control computer is mainly used for an industrial real-time measurement and control system, the PLC host (lower computer) (2) selects a DVP series programmable controller SS modular standard functional host DVP14SS11R2 of a Taida, a host power supply is DC24V, the temperature modules (3), each PLC (lower computer) (2) is connected with four temperature sensors (4), and the temperature sensors (4) select platinum temperature sensors (PT1003 line 100 omega 3850PPM/° C).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010239935.0A CN111300619A (en) | 2020-03-31 | 2020-03-31 | Automatic temperature control system of prefabricated box girder steam health preserving |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010239935.0A CN111300619A (en) | 2020-03-31 | 2020-03-31 | Automatic temperature control system of prefabricated box girder steam health preserving |
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| CN111300619A true CN111300619A (en) | 2020-06-19 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112720815A (en) * | 2020-12-16 | 2021-04-30 | 保利长大工程有限公司 | Steam curing system for bridge concrete precast beam plate |
| CN116793098A (en) * | 2023-08-29 | 2023-09-22 | 山西华茂智能新材料有限公司 | Waste heat recycling method for annealing process slow cooling section of spheroidal graphite cast tube |
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