Share comprehensive inspection and reinforcement solutions for bridges

At present, there are many critically ill, old, and low-load bridges in our country, some bridges are about to reach their design service life, and some bridges are "aging before they die".

Therefore, timely and comprehensive inspection of the bridge, fully understanding the safety status of the bridge structure, and taking effective reinforcement measures for the problem bridge are one of the important ways to avoid major accidents and disasters. Below we will introduce you to the comprehensive inspection content of bridges and conventional reinforcement methods.

1. Comprehensive inspection of bridges

(1) Inspect and measure the approach road and the surrounding environment of the bridge site

1. Check whether the connection between the main bridge and the approach bridge and approach road (line) is normal, and whether there is any change compared with the situation at the time of completion.

2. Whether the bridge site and its vicinity water flow channel have changed, and if necessary, the water flow speed and direction of the main river channel should also be measured; whether the clear width under the bridge has changed; Whether the local scouring at the pier is increased compared with the relevant design data.

3. Whether the soil and stone cone slope of the bridgehead on both sides of the river has been scoured, slipped and damaged.

(2) Measure the elevation and alignment of the whole bridge

1. The elevation of the bridge is related to the alignment, but there is a difference. The former refers to a certain pointElevation value, the latter is the connection of the relevant points of the bridge. A bridge with good design and construction quality should meet the design expectations in terms of elevation and alignment.

2. The main parts and items of measurement are: the top surface of the supporting cushion (i.e., the support backing plate) of the pier, the top surface of the bearing platform and the elevation at the bottom of the beam; The pier body is tilted in the vertical and horizontal directions of the bridge. (1) For cable-stayed bridges and suspension bridges, the main tower body should also be measured whether there is a deviation and tilt in the longitudinal and transverse directions of the bridge, and the displacement of the top of the tower. (2) For suspension bridges, the alignment of the main cable should also be measured. (3) For arch bridges, the alignment of the arch rib axis should also be measured.

(3) Inspection and measurement of beam arches of the wall

1. Check whether the worker has weathering, peeling, damage and cracks, and pay special attention to the variable section, reinforcement and repair andWaterproof layersituation. For the peeling and cracks of the work, attention should be paid to the rust of the steel bars.

2. Reinforced concrete beams should focus on checking the width of more than 0.2mmVertical cracks, and pay attention to check whether there are oblique cracks and longitudinal cracks in the forward direction. The change of the upper arch of the prestressed reinforced steel composite beam should be observed, and pay attention to check whether there are vertical cracks perpendicular to the main bar that are not allowed.

3. The arch bridge should be measured in realityarch axisand arch circle (or arch rib) size, and check them for lateral (perpendicular to the direction of the route) cracks.

(4)Steel structureCheck the measurement

1. Check the integrity of the paint coating of steel structure components, whether there is peeling, peeling, rust spots, etc. In particular, there is rust in parts that are prone to water accumulation and dust accumulation or lack of ventilation. If the rust is serious, the actual remaining thickness of the steel plate or component should be measured to consider the impact of section weakening.

2. Check whether the components have cracks, perforations, hard injuries, hard bends, crooked twists, burst skin and material interlayers. Pay special attention to whether there are fatigue cracks in the following parts: withstand tensile force orRepeated stressThe members are withNode boardthe connection or rod (component) joint; Due to the damage, the section of the rod (component) is weakened andStress concentrationplace; the connecting angle steel between the longitudinal beam and the cross beam; Upper flange angle steel of longitudinal beam without cover; the connection point of the longitudinal connection system between the main beams; Single cut rivet; Substrate at and near the weld end; welds at the connection between the U-shaped rib and the diaphragm, etc.

3. InspectionSteel box girdersWhether there is any abnormality in the large annular weld (i.e., the perimeter weld of the roof→web→ bottom plate→ web) and the U-shaped ribbed patch section of the same section of the same section.

4. Check whether the rivet head is rusted and whether the rivet is loose. Check whether the high-strength bolts are intact and whether there is looseness and delayed breakage. whether there is a reduction in friction force due to rust or other reasons; And pay close attention to the slippage of the nodeArchChange.

(5) Inspection and measurement of masonry

One of the characteristics of masonry masonry is that it has less tensile strength, greater structural brittleness, and the cracking load is relatively close to or almost equal to the failure load. Therefore, when masonry appears as a resultLoadCracks are often a feature or precursor to masonry failure.

(6) Inspection and measurement of piers and foundations

1. The main manifestations of the defects of the pier are: cracks, spalling, cavities, exposed steel bars and rust, aging, deformation and displacement, etc.

2. During inspection, the specific location, width, length and depth of cracks and damages should be measured and described, and drawn into a map.

(7) Inspection of foundation

When it is found that the pier has settlement, tilt and displacement, the foundation must be detected and discussed. It is more difficult and troublesome to inspect the foundation of the bridge. It can be used by contact and drilling sampling, or it can be tested by load plate. However, it is difficult to do it in situ, often only close to the foundation in situ. For rock foundations, they can be inspected at the outcropping sites of the bedrock.

2. Conventional bridge reinforcement methods

Bridge reinforcement is to make the components and even the entire structure through certain measuresCarrying capacityand its use performance has been improved to meet new requirements. After the bridge is strengthened, the service life of the bridge can be extended, and the loss of people and property caused by the bridge collapse can be prevented and avoided.

1. The bridge deck reinforcement layer reinforcement method chiseled or chiseled all the original bridge deck pavements, and then laid a certain thickness of reinforcement layer to increase the effective height of the main beam and improve the lateral distribution capacity of the bridge load, so as to improve the bearing capacity of a single girder or the overall bearing capacity of the bridge structure.

2、Paste steel plate reinforcement methodThe pasted steel plate reinforcement method is a structural reinforcement method of bonding steel plates and concrete with epoxy resin, which has a fast construction, no wet operation on site or only a small amount of wet operation such as plastering, which has little impact on production and life, and has a small impact on the appearance and original structure after reinforcementHeadroomNo significant effect. But the reinforcement effect depends a lotAdhesive processwith operating level, suitable for withstandingStaticbending orTension Membersreinforcement.

3. Enlarged section reinforcement method Increasing the section method is used to enlarge the concrete structureCross-sectional areaand reinforcement for reinforcement. This reinforcement method requires the bridge to be reinforcedsubstructureable to withstand more dead weight, able to provide higherBearing capacity

4. Paste carbon fiber composite reinforcement method Carbon fiber has the advantages of high strength, light material and corrosion resistance. This method uses a special resin to paste carbon fiber on the tensile surface of the concrete structure, and the carbon fiber and the original structure form a new stress whole, and the carbon fiber and the steel bar bear the load together, reducing the stress of the steel bar, so that the structure can achieve the effect of reinforcement and reinforcement. It has almost no increase in the weight and cross-sectional size of the structure, does not change the headroom, is convenient for construction, almost does not cause new damage to the original structure, and has good corrosion resistance, durability and durabilityFatigue resistanceand other advantages.

5、Extracorporeal prestress reinforcement methodExternal prestress reinforcement is usually reinforced by adding prestressed stiffening wire cables, prestressed coarse steel bars or prestressed carbon fiber plates at the bottom of the beam or the lower part of the beam side, and anchored at both ends of the beam respectively.

6. Add stressed components and changeStructural systemWhen the bearing capacity of the bridge is insufficient or the bridge is damaged due to various reasons, new stressed components can be added to the original structure through certain processes and structural measures, so as to improve the bearing capacity of the structure.

7. Add horizontal connection reinforcement method To increase horizontal connection, it is also a more common reinforcement method in recent years. This method improves the lateral distribution law of the load of the superstructure by adding the lateral connection of the bridge, so as to achieve the reinforcement method to improve the overall bearing capacity of the structure.

CCCC Road and Bridge Technology Co., Ltd. was established in 2009 and is professionalEngineering inspectionmonitoring, urban safety monitoring, early warning and evaluation, and digital intelligent research and development as one of the composite typesHigh technologyGroup enterprises.

At present, it has obtained the industry testing qualifications issued by the railway industry, highway industry and construction industry, as well as the measurement certification qualification of the Hebei Provincial Technical Supervision BureauChina Transportation Construction Supervision AssociationThe deputy secretary-general unit of the test and testing committee and the director unit of the Zhongguancun Zhimeng Environmental Civil Engineering Intelligent Testing and Monitoring Industry Alliance is the only testing institution in the construction and highway testing industry in Hebei Province that has both "specialized, special and new" and "high-tech enterprises".

Combined with years of advanced experience in the industry, integrating the development needs of the digital economy and national security system, we will build an "engineering hospital+"Intelligent detection+ technology leadership + digital empowerment"Brand strategy, forming engineering testing, urban safety monitoring, digital research and development, and wisdomSmart designFour major business segments.

The company has strong technical strength, and currently has a team of high-quality engineering doctors, including railway engineering, urban roads and highways, bridge engineering,Tunnel engineering, construction engineering, water conservancy engineering,Engineering geophysical prospecting, safety technology, electricity, signaling,Integrated circuits, intelligent science and other majors. The company is fully equipped with testing, testing and monitoring instruments, with more than 1,000 sets of instruments and equipment for testing, surveying and mapping, which provides hardware guarantee for the scientific and accurate testing and monitoring data.

Since its establishment, the company's research projects have reached the international advanced and domestic leading level for many times, relying on the enterprise science and technology collaborative innovation center to achieve many new breakthroughs, and have passed for many yearsNational high-tech enterprise recognition, actively participate in the formulation of national and industry standards, and independently innovate a number of thingsIntellectual PropertyTechnology.

The company always adheres to and implements "fair, just, scientific and efficient"Quality policyWith the business philosophy of "integrity based on integrity, innovation and far-reaching", backed by "high standards, high starting point, and modern management", we are committed to building a modern, technological, and compound professional and technical institution based on engineering testing, with urban safety monitoring and digital research and development as the highlights, and is determined to become a modern, technology-based, and compound professional and technical institution with owner satisfaction, employee satisfaction, high partner dependence and high industry recognition.

Some bridge testing cases

1. Static load test and testing of 26 bridges of Inner Mongolia High-grade Highway Construction and Development Co., Ltd.;

2、Muzati River, XinjiangPermanent bridges No. 1, 2 and 3 and temporary bridges No. 4 of tertiary hydropower stationsStatic loadtest and testing;

3、ZhangjiakouStatic load test and detection of bridges;

4. Static load test and detection of Beijing Fangshan Qiyi Bridge bridge;

5. Inner Mongolia National Highway 110 overpass completion acceptance test and testing;

6. Static load test and testing of the first and second bridges of the Yellow River in Baomao, Inner Mongolia.

7. Static load test test and testing of Pingshan Yehe Bridge.