Which big brother and sister can tell me the testing method and testing basis of corrosion resistant

The test standard for impermeable concrete is PT P 10+. where p is the impermeability level required by the design. Added: s is the old specification, p is the new specification representation. Impermeability tester is used.

Specimen preparation each group of specimens is six, such as when using manual insertion and tamping, it is loaded with concrete mixture in two layers, and each layer is inserted and pounded 25 times, and is cured under standard conditions, if combined with engineering needs, it is made at the pouring site, and each unit of engineering parts is not less than two groups, of which at least one group should be cured under standard conditions.

The rest of the specimens are cured under the same conditions as the components, and the curing period of the test blocks is not less than 28d and not more than 90d. The mold is removed 24 hours after the specimen is formed, and the cement slurry film at both ends is brushed with a wire brush, and the standard curing age is 28d.

After the specimen expires, take it out, dry the surface, brush both ends with a wire brush, and after the surface is dry, roll a layer of melted sealing material (butter mixed with talcum powder) on the side of the specimen and load it on the impermeability meter for testing.

The impermeability of concrete is expressed in terms of impermeability class (p) or permeability coefficient. China's standard adopts impermeability grade. The impermeability grade is determined by the maximum water pressure that can be withstood by the standard specimen at the age of 28 days and tested according to the standard test method.

GB 50164 "Concrete Quality Control Standard" According to the maximum water pressure that concrete specimens can withstand during the impermeability test, the impermeability grades of concrete are divided into five grades: P4, P6, P8, P10, and P12. Correspondingly, it indicates the maximum water pressure of 4 of the 6 specimens in a group of 6 specimens during the concrete impermeability test, when there is no water seepage. The impermeable water pressure value required for the fitting should be higher than the design MPA.

The mixture ratio with the largest water-cement ratio should be used for the impermeability test

Impermeability grade Maximum water-cement ratio C20 C30 C30 or more P6 P8 P12 >P12 The impermeability test results should meet the requirements of the following formula: Pt P 10 in the formula P - the impermeability level required by the design Supplement, S is the old specification. P is the new standard representation method The impermeability index of ordinary concrete reaches P10

Look at the parts and groups of unqualified test blocks. One group is unqualified, one group is drilled, and so on... What is the normative basis? You are responsible for handing over the money, and someone will drill the core.

The unqualified concrete pressure test part indicates that the strength is not enough, and it is based on the corresponding specifications. The specification used for concrete core pulling is the technical specification CECS 03:2007 for detecting concrete strength by core drilling method.

Concrete refers to the general term for engineering composite materials that are cemented into aggregates by cementitious materials. The word concrete usually refers to the use of cement as cementitious material, sand and stone as aggregates; With water, admixtures and admixtures in a certain proportion, the cement concrete obtained by mixing, also known as ordinary concrete, is widely used in civil engineering. When preparing concrete, first of all, according to the requirements of the project for workability, strength, durability, etc., the raw materials should be reasonably selected and their matching ratio should be determined, so as to achieve the purpose of economic application.

The design of the concrete mix is usually carried out according to the requirements of the water-cement ratio law. The calculation of material dosage is mainly based on the assumption bulk density method or the absolute volume method. Concrete material is a durable material, but it is essentially a non-uniform porous material, under the erosion of carbon dioxide, water, chloride ions, sulfate and other media, it is inevitable to be affected by external factors and corroded, concrete will accelerate the damage, and the service life is greatly shortened.

Detection method with steel bar protective layer thickness detector, first to find out the position of the steel bar line, in the detection, the number of detection and supervision to determine. For evaluation: "Code for Construction Quality Acceptance of Concrete Junction Engineering" G50204-2002 (2010 Edition).

1. Allowable deviation and inspection method of steel installation position). In the items to be inspected (not tested), the allowable deviation of the thickness of the protective layer of the stressed steel bar is 10mm for the foundation, 5mm for columns and beams, and 3mm for plates, walls and shells. Its note:

2. In the table, the qualified point rate of the thickness of the protective layer of the longitudinal stressed steel bar on the upper part of the beam and plate components shall reach 90% or more, and shall not exceed the multiple size deviation of the value in the table.

Second, the thickness inspection of the protective layer of the reinforcement of the structural entity.

Only beam and plate components are allowed to be inspected.

During the inspection of the thickness of the reinforcement protective layer, the allowable deviation of the thickness of the longitudinal stressed reinforcement protective layer is 10mm, 7mm for beam components and 8mm and 5mm for plate components.

The thickness of the protective layer of the longitudinal stressed steel bars of beams and plate components should be accepted separately.

The acceptance of the thickness of the reinforcement protective layer of the structural entity shall comply with the following provisions:

1. When the pass rate of the thickness inspection of all reinforcement protective layers is 90% or above, the inspection results of the thickness of the reinforcement protective layer shall be judged to be qualified;

2. When the pass point rate of the thickness inspection of all steel reinforcement protective layers is less than 90% but not less than 80%, the same component can be extracted for inspection; When the pass rate calculated by the sum of the two samples is 90% or more, the test result of the thickness of the reinforcement protective layer should still be judged to be qualified;

3. The maximum deviation of the unqualified points in the results of each sampling inspection shall not be greater than the times of the allowable deviation specified in this appendix.

Concrete press, specific test standard GB T 50081

Entity testing is to use instruments to carry out concrete rebound test or reinforcement protective layer detection on the structure that has been completed, as a kind of inspection of structural quality in addition to concrete test blocks, and it is a mandatory item in the main body of the structure inspection. Before the main body is accepted, the main body must be tested and qualified. Concrete generally has a strength test and a steel bar cover test.

Methods include rebound method, ultrasonic rebound comprehensive method, coring method (damage method). The floor thickness detection method is the ultrasonic countermeasure method.

What are the regulations for the physical inspection of concrete structures?

There are two types of items for the physical inspection of concrete structures: concrete strength and the thickness of the reinforcement protective layer of the main reinforcement of beams and slabs.

The concrete strength physical test can be carried out by the method of "structural solid test with the same condition specimen". According to the provisions of the Code for Acceptance of Construction Quality of Concrete Structure Engineering [GB 50204-2002 (2011 Edition)] "Structural Entity Inspection" and Appendix D "Specimens with the Same Conditions for Structural Entity Inspection", they are summarized as follows:

1. The production of the "test piece with the same conditions for the inspection of structural entities" shall be witnessed by the supervision unit, organized and implemented by the construction unit, and sent to a testing institution with witness qualification for testing.

2. The number of specimens in the appendix is retained: according to the strength level. For concrete with a strength grade above C20, at least 3 groups of specimens should be left in each strength grade, and the specification suggests that more than 10 groups should be left in each strength grade when conditions permit.

4. Appendix Paragraph 2 The specimens under the same conditions for structural entity inspection shall be maintained under the same conditions as the structure. The test was carried out when the curing age reached 600 ·d. The pressure test result of the specimen should be multiplied by the conversion coefficient and judged according to the "Concrete Strength Inspection and Evaluation Standard" (GB T 50107-2011).

5. Acceptance under abnormal conditions: when the strength of the maintenance specimen under the same conditions is judged to be unqualified, a testing institution with the corresponding qualification level shall be entrusted to conduct testing in accordance with the provisions of the relevant national standards, and then accept the test according to the test results.

The standard of cement, the formula of concrete, the requirements of steel bars "whether to meet international standards", the time of demoulding of finished concrete, the length of curing time "according to the temperature", the strength of concrete when lifting, the curing time after demolition, the position of the embedded line pipe and the bottom box of the line pipe in the concrete products, whether the line pipe and the bottom box, the line pipe joint have no glue, and the quality requirements of the line pipe and the bottom box. Wait a minute... There are also requirements for big pebbles, small pebbles, river sand...

As far as I know, the mainland does not have very high requirements for these!

The other is the construction specification of highway tunnels and railway tunnels.