CN103104097B - Ultra-long concrete base arrangement cancels the recursion cross construction method of temperature post-cast strip - Google Patents

Abstract

The invention discloses a kind of recursion cross construction method that ultra-long concrete base arrangement cancels temperature post-cast strip, temperature post-cast strip can be cancelled, effectively can control the thermal stresses of ultra-long concrete base arrangement simultaneously, reduce Concrete bottom plate structure cracking, and accelerate duration raising concrete construction quality, according to concrete maximum primary concreting length, ultra-long concrete base plate is divided into plural concrete casting castable, calculate the maximum temperature stress of each block concrete castable in whole work progress, maximum temperature stress is made all to be less than concrete the maximum tensile strength, by concrete casting castable by the precedence of different operation from one of scene to other end continuous recursion block-by-block moulding by casting, period utilize wireless thermodetector and oily avert by prayers formula strain meter to every block concrete castable and between temperature, STRESS VARIATION carries out Real-Time Monitoring, to reach control and maintenance, fundamentally prevent concrete structure from ftractureing.

Description

Ultra-long concrete base arrangement cancels the recursion cross construction method of temperature post-cast strip

Technical field

The present invention relates to a kind of construction method of ultra-long concrete base arrangement, especially a kind of ultra-long concrete base arrangement cancels the recursion cross construction method of temperature post-cast strip.

Background technology

Ultra-long concrete base arrangement is the temperature shrinkage fracture avoiding overlength to cause operating period and construction period, needs set temperature ater-casting.Temperature post-cast strip is generally wide 1 ~ 2 meter, spacing 40 ~ 50 meters, and filling time of temperature post-cast strip is after temperature post-cast strip both sides underplate concrete has been built 2 ~ 3 months.But ater-casting can not solve all bottom slab crack problems, namely it is not omnipotent, many base plates leaving temperature post-cast strip also often ftracture, temperature post-cast strip has become Concrete bottom plate structure and to have constructed the serious hindrance further developed on the contrary, itself bring a series of quality and construction difficult problem as: indwelling after two months temperature post-cast strip is filled by various sewage and building waste, ater-casting cleaning work is difficult, and construction quality is difficult to ensure; Before ater-casting is filled, basement is in the state of leaking all the time, has a strong impact on construction and carries out, and the necessary long-time precipitation of the soil body, ater-casting place base plate long-term existence stability against floating potential safety hazard; The contradiction of ater-casting indwelling and pre-stress construction, when presstressed reinforcing steel strides across after-pouring band, prestressing force must wait after-pouring to close and could stretch-draw after reaching intensity, has a strong impact on construction speed; The problems such as when ater-casting and support replacement base plate horizontal force resistant is not enough; The invention provides a kind of construction method and can cancel temperature post-cast strip, effectively can control the thermal stresses of ultra-long concrete base arrangement simultaneously, reduce Concrete bottom plate structure cracking, and accelerate duration raising concrete construction quality.

Summary of the invention

Technical problem to be solved by this invention is to provide one can replace temperature post-cast strip, the thermal stresses of effective control ultra-long concrete base arrangement, reduce Concrete bottom plate structure cracking, and accelerate the recursion cross construction method that the duration improves the ultra-long concrete base arrangement cancellation temperature post-cast strip of concrete construction quality.

For realizing above-mentioned technique effect, the invention discloses a kind of recursion cross construction method that ultra-long concrete base arrangement cancels temperature post-cast strip, described construction method mainly comprises the following steps:

Concrete maximum primary concreting length is calculated according to mix proportion;

According to described maximum primary concreting length, described ultra-long concrete base plate is divided into plural concrete casting castable;

Calculate the maximum temperature stress of each block concrete castable in whole work progress, and build by adjustment adjacent concrete castable the maximum temperature stress that the time interval adjusts concrete casting castable described in each block, make described maximum temperature stress all be less than concrete the maximum tensile strength;

By described concrete casting castable by the precedence of different operation from one of scene to other end continuous recursion block-by-block moulding by casting;

Complete the cast of described ultra-long concrete.

The present invention further improves and is, described concrete casting castable is all less than described maximum primary concreting length.

The present invention further improves and is, the size of described concrete casting castable is 40-50m*40-50m.

The present invention further improves and is, is embedded into wireless thermodetector and measures temperature in described concrete casting castable, and carry out thermostatic curing according to measurement result to concrete casting castable described in each block when concrete casting castable is built described in each block.

The present invention further improves and is, the temperature obtained based on described wireless thermodetector measurement carries out following maintenance operations:

At described Massive Concrete Blocks in early days due to the release of hydration heat of cement, in the process that occurrence temperature rises, to the spray carrying out water outside the template of described Massive Concrete Blocks;

Stop spray when described Massive Concrete Blocks internal temperature rises and reaches peak value, and at Massive Concrete Blocks outer side covers film, Massive Concrete Blocks is incubated, delay the rate of temperature fall of body of wall.

The present invention further improves and is, the pre-buried oily avert by prayers formula strain meter in the constuction joint place between adjacent two block concrete castables, measures and calculate the pressure of adjacent two block concrete castables at described constuction joint in conjunction with described wireless thermodetector.

The present invention further improves and is, described adjacent two block concrete castables deduct the temperature strain of described oily avert by prayers formula strain meter at the reading strain equaling described oily avert by prayers formula strain meter by stress-strain that the pressure of described constuction joint is formed, and the actual temperature change course that the temperature strain of described oily avert by prayers formula strain meter equals the described oily avert by prayers formula strain meter utilizing described wireless thermodetector to measure is multiplied by the coefficient of thermal expansion of oil in the oil sac of described oily avert by prayers formula strain meter.

The present invention is owing to have employed above technical scheme, making it have following beneficial effect is: according to concrete maximum primary concreting length, ultra-long concrete base plate is divided into plural concrete casting castable, calculate the maximum temperature stress of each block concrete castable in whole work progress, maximum temperature stress is made all to be less than concrete the maximum tensile strength, by concrete casting castable by the precedence of different operation from one of scene to other end continuous recursion block-by-block moulding by casting, period utilize wireless thermodetector and oily avert by prayers formula strain meter to every block concrete castable and between temperature, STRESS VARIATION carries out Real-Time Monitoring, to reach control and maintenance, fundamentally prevent Concrete bottom plate structure from ftractureing.

Accompanying drawing explanation

Fig. 1 is the flow chart that ultra-long concrete base arrangement of the present invention cancels the recursion cross construction method of temperature post-cast strip.

Fig. 2 is the schematic diagram that ultra-long concrete base arrangement of the present invention cancels the first block concrete pour of the recursion cross construction method of temperature post-cast strip.

Fig. 3 is the schematic diagram that ultra-long concrete base arrangement of the present invention cancels the second block concrete pour of the recursion cross construction method of temperature post-cast strip.

Fig. 4 is the schematic diagram that ultra-long concrete base arrangement of the present invention cancels the 3rd block concrete pour of the recursion cross construction method of temperature post-cast strip.

Fig. 5 is the schematic diagram that ultra-long concrete base arrangement of the present invention cancels the 4th block concrete pour of the recursion cross construction method of temperature post-cast strip.

Fig. 6 is the Massive Concrete Blocks internal water heat-transmission temperature curve under prior art.

Fig. 7 is the Massive Concrete Blocks internal water heat-transmission temperature curve of the present invention after maintenance.

Detailed description of the invention

For the benefit of to the further understanding of structure of the present invention, below in conjunction with specific embodiment, the invention will be further described.

Consult shown in Fig. 1, the recursion cross construction method that ultra-long concrete base arrangement of the present invention cancels temperature post-cast strip can cancel temperature post-cast strip, effectively can control the thermal stresses of ultra-long concrete base arrangement simultaneously, reduce Concrete bottom plate structure cracking, and accelerate duration raising concrete construction quality, construction method is as follows:

S01 calculates concrete maximum primary concreting length according to mix proportion;

Described ultra-long concrete base plate is divided into plural concrete casting castable by maximum primary concreting length by S02;

S03 calculates the maximum temperature stress of each block concrete castable in whole work progress, and build by adjustment adjacent concrete castable the maximum temperature stress that the time interval adjusts concrete casting castable described in each block, make described maximum temperature stress all be less than concrete the maximum tensile strength;

S04 by described concrete casting castable by the precedence of different operation from one of scene to other end continuous recursion block-by-block moulding by casting;

Shown in composition graphs 2 ~ 5, first build the first block concrete castable 11, wireless thermodetector is embedded into when pouring into a mould, and oily avert by prayers formula strain meter is imbedded at the constuction joint place of the first block concrete castable 11 and the second block concrete castable 12 before cast second block concrete castable 12, pour into a mould the second block concrete castable 12, and pre-buried wireless thermodetector, by that analogy, 3rd block concrete castable 13, 4th block concrete castable 14 and other pouring concrete blocks, by the precedence of different operation from one of scene to other end continuous recursion block-by-block moulding by casting,

S05 completes the cast of described ultra-long concrete base plate.

The Specific construction content that ultra-long concrete base arrangement of the present invention cancels the recursion cross construction method of temperature post-cast strip is as follows:

(1) by the reasonable arrangement to site operation progress, flowing water, place, first ultra-long concrete base arrangement is divided into some concrete casting castables, the concrete casting castable number divided requires to form construction flowing water, the size of each block general is 40-50m*40-50m, underplate concrete construction is by the precedence of different operation, from one of scene to other end, continuous recursion is carried out, and does not stay between two block concretes and establish temperature post-cast strip.

(2) each operation that each block concrete castable is constructed is arranged sequentially, calculate each operation as surveying setting-out, set up steel pipe support, formwork supporting plate, wire-tie, the operation such as concreting, curing concrete determining the time required under the quantity of labour force, determine to build the time what determine every adjacent block concrete casting castable under the quantity of labour force, thus obtain every adjacent block concrete casting castable build the time interval, this time interval is designated as T _i, general adjacent block concrete casting castable build Separation control in 5-10 days, after 5-10 days, namely adjacent block concrete casting castable builds connected, and no longer stays between two pieces of base plates and establish temperature post-cast strip.

(3) concrete raw material and mix proportion are strictly controlled, reduce the cementitious material in concrete and water consumption as far as possible.

(4) after determining mix proportion, by formula:

$\[L_{max}\]=1.5\sqrt{\frac{HE}{Cx}}ar\cosh \frac{\left|\mathrm{\α}T\right|}{\left|\mathrm{\α}T\right|-\mathrm{\ϵ}\mathrm{\ρ}}$

Calculate concrete maximum primary concreting length, determine that each Massive Concrete Blocks divided all is less than the maximum primary concreting length of calculating (in formula: H-base plate thickness; E-modulus of elasticity of concrete; T-concrete total cooling; The horizontal resistance coefficient of Cx-ground; α-concrete coefficient of thermal expansion; ε ρ-concrete ultimate tensile strength).

(5) by formula:

${\mathrm{\σ}}_i^1(3~T_i)=\frac{\mathrm{\α}}{1-\mathrm{\μ}}{\mathrm{\ΔT}}_{3~7}\×\frac{E\left(3\right)+E\left(T_i\right)}{2}\×H(5~T_i)\×\frac{R_{Li1}\left(3\right)+R_{Li1}\left(T_i\right)}{2}$

(in formula: build T for-the i-th piece _imaximum temperature stress after it; build T for-the i-th piece _icore cooling in it; E (3), E (T _i)-concrete 3 days and T _iit bullet mould; H (5 ~ T _i)-concrete is loaded into T on the 5th day _iit coefficient of relaxation; R _li1(3)-the i-th piece build after the constraint factor of the 3rd day; R _li1(T _i)-i-th piece builds rear T _iit constraint factor)

And formula:

$\begin{array}{c}{\mathrm{\σ}}_i^j{\left(\left(j-1\right)\×T_i)~j\×T\right)}_i={\mathrm{\σ}}_i^1(3~T_i)\×\frac{H(5~j\×T_j)}{H(5~7)}+{\mathrm{\σ}}_i^2(7~14)\×\frac{H(7~j\×T_i)}{H(7~14)}+{\mathrm{\σ}}_i^3(14~21)\×\frac{H(14~j\×T_i)}{H(14~21)}+...+\\ {\mathrm{\σ}}_i^{j-1}\left(\right(j-2)\×T_i~(j-1)\×T_i)\×\frac{H\left(\right(j-2)\×T_i~(j)\×T_i)}{H\left(\right(j-2)\×T_i~(j-1)\×T_i)}+\frac{\mathrm{\α}}{1-\mathrm{\μ}}{\mathrm{\ΔT}}_{(j-1)\×T_i~j\×T_i}\×\frac{E\left(\right(j-1)\×T_i)+E(j\×T_i)}{2}\\ \×H\left(\left(j-1\right)\×T_i)~j\×T_i\right)\×\frac{R_{Lij}\left(\right(j-1)\×T_i)+R_{Lij}(j\×T_i)}{2}\end{array}$

(in formula: build j × T for-the i-th piece _imaximum temperature stress after it; H (5 ~ j × T _i)-concrete is loaded into j × T on the 5th day _iit coefficient of relaxation; build for-the i-th piece _{(j-1) ×}t _iarrive _{j ×}t _icore cooling in it; E ((j-1) × T _i)-concrete _{(j-1) ×}t _iit bullet mould; R _lij((j-1) × T _i)-i-th piece build after the _{(j-1) ×}t _iit constraint factor)

Calculate the maximum temperature stress of each block concrete pour in whole work progress, guarantee that the maximum temperature stress of each block concrete pour in whole work progress is all less than concrete the maximum tensile strength, when by calculating the thermal stresses that finds that there is Massive Concrete Blocks when being greater than concrete tensile strength sometime, then must build time interval T by adjustment adjacent block Massive Concrete Blocks _ireduce the thermal stresses of this part.

(6) be embedded into the temperature in wireless thermodetector measurement concrete casting castable when each block concrete castable is built, and according to measurement result, thermostatic curing carried out to concrete casting castable described in each block.Specifically consult shown in Fig. 6, concrete casting castable is in early days due to the release of hydration heat of cement, temperature can be caused to rise and to cause volume expansion, after hydration heat of cement rate of release slows down, concrete wall volume contraction is caused because concrete casting castable surface radiating can cause temperature to decline, and the Swelling and contraction of concrete casting castable will be subject to the constraint of peripheral member as base plate or basis, can not freely occur, thus thermal stresses is produced in concrete wall, when thermal stresses is greater than concrete tensile strength, namely temperature shrinkage fracture can be produced.Therefore in order to reduce the generation of temperature shrinkage fracture, wireless thermodetector is utilized at Massive Concrete Blocks in early days due to the release of hydration heat of cement, in the process that occurrence temperature rises, to the spray carrying out water outside template; Spray is stopped when Massive Concrete Blocks internal temperature rises and reaches peak value, and at Massive Concrete Blocks outer side covers film, body of wall is incubated, delay the rate of temperature fall of Massive Concrete Blocks, carry out the maintenance work of Massive Concrete Blocks, the temperature value that wireless thermodetector is measured reaches stable, as shown in Figure 7.

(7) imbed oily avert by prayers formula strain meter at the constuction joint place of adjacent two block concrete castables, the stress of adjacent two block concretes at constuction joint measured by combining wireless temperature measurer, and according to stress intensity, change the concrete maintenance work in constuction joint place.Because the concrete defevent experiment on constuction joint both sides is built, the concrete strength of constuction joint place concrete strength ratio primary concreting is low, simultaneously at constuction joint place concrete due to first after-pouring, the concrete of building for rear time can produce the Swelling and contraction of volume due to heat of hydration reason, this cubic deformation can form compressive stress and tensile stress on the interface of constuction joint New-old concrete, be exactly the constuction joint place generation pressure when rear concreting heats up particularly, when rear concrete cooling of time to build, constuction joint place stress transfers tensile stress to by compressive stress gradually, when tensile stress is greater than the concrete tensile strength in constuction joint place, constuction joint will ftracture.The concrete stress size at current constuction joint place can't by concrete formulae discovery out, for the situation of change understanding constuction joint place stress is necessary the size of surveying out constuction joint place thermal stresses, thus concrete maintenance process is stitched at guiding construction place, avoid the concrete cracking in constuction joint place.When using oily avert by prayers formula strain meter to measure constuction joint place stress, because the concrete of building for the second time has the process of a hydration heat temperature change, therefore the oily avert by prayers formula strain meter being embedded in constuction joint place also has the process of a corresponding variations in temperature, the reading strain that now oily avert by prayers formula strain meter is read is the temperature strain sum caused by stress-strain and oil sac variations in temperature of oil sac, wireless thermodetector must be utilized to measure the actual temperature change course of oily avert by prayers formula strain meter, be multiplied by coefficient of thermal expansion oily in oil sac with this thermal history thus obtain the temperature strain of oily avert by prayers formula strain meter, constuction joint place accurately finally could be obtained again concrete real by stress-strain by the temperature strain that the oily avert by prayers formula strain meter strain value read deducts oily avert by prayers formula strain meter.

Below embodiment is to invention has been detailed description by reference to the accompanying drawings, and those skilled in the art can make many variations example to the present invention according to the above description.Thus, some details in embodiment should not form limitation of the invention, the present invention by the scope that defines using appended claims as protection scope of the present invention.

Claims (6)

1. ultra-long concrete base arrangement cancels a recursion cross construction method for temperature post-cast strip, it is characterized in that described construction method mainly comprises the following steps:

Concrete maximum primary concreting length is calculated according to mix proportion;

According to described maximum primary concreting length, described ultra-long concrete base plate is divided into plural concrete casting castable;

Calculate the maximum temperature stress of each block concrete castable in whole work progress, and build by adjustment adjacent concrete castable the maximum temperature stress that the time interval adjusts concrete casting castable described in each block, make described maximum temperature stress all be less than concrete the maximum tensile strength;

By described concrete casting castable by the precedence of different operation from one of scene to other end continuous recursion block-by-block moulding by casting;

Complete the cast of described ultra-long concrete base plate;

Wherein, described concrete casting castable is all less than described maximum primary concreting length.

2. construction method as claimed in claim 1, is characterized in that: the size of described concrete casting castable is 40-50m*40-50m.

3. construction method as claimed in claim 1, it is characterized in that: be embedded into wireless thermodetector when concrete casting castable is built described in each block and measure temperature in described concrete casting castable, and according to measurement result, thermostatic curing is carried out to concrete casting castable described in each block.

4. construction method as claimed in claim 3, is characterized in that the temperature obtained based on described wireless thermodetector measurement carries out following maintenance operations:

At described Massive Concrete Blocks in early days due to the release of hydration heat of cement, in the process that occurrence temperature rises, to the spray carrying out water outside the template of described Massive Concrete Blocks;

Stop spray when described Massive Concrete Blocks internal temperature rises and reaches peak value, and at Massive Concrete Blocks outer side covers film, Massive Concrete Blocks is incubated, delay the rate of temperature fall of body of wall.

5. construction method as claimed in claim 3, is characterized in that: the pre-buried oily avert by prayers formula strain meter in the constuction joint place between adjacent two block concrete castables, measures and calculate the pressure of adjacent two block concrete castables at described constuction joint in conjunction with described wireless thermodetector.

6. construction method as claimed in claim 5, it is characterized in that: described adjacent two block concrete castables deduct the temperature strain of described oily avert by prayers formula strain meter at the reading strain equaling described oily avert by prayers formula strain meter by stress-strain that the pressure of described constuction joint is formed, the actual temperature change course that the temperature strain of described oily avert by prayers formula strain meter equals the described oily avert by prayers formula strain meter utilizing described wireless thermodetector to measure is multiplied by the coefficient of thermal expansion of oil in the oil sac of described oily avert by prayers formula strain meter.