On the issue of road and bridge construction and Countermeasures

[Abstract] With the construction of roads and bridges in China expanded scale in road construction, bridges occupy a large amount of work, but the resulting quality problems are increasing, these problems are many and varied reasons for this paper begins by describing the proposed bridge construction in some of the problems, results described measures to improve these issues.

[Keywords] roads and bridges, construction, problems, strategies

Road is an important lifeline of national economy, because of its flexibility and unique advantages of other modes of transport play an irreplaceable role of national road construction is one of the most important basic industries, and its rapid development, for the promotion of the national economy , driving the development of other related industries have very important significance. a vast territory, and more mountainous terrain, coupled with China is in the primary stage of socialism, economic development is uneven, the overall level is not high, so the construction of more roads in China China's economic development was its special importance to some extent we can say that the quality of roads and bridges is often due to careless construction workers caused by, for road and bridge construction process should be noted that attention should be problems, and construction workers did not give the necessary attention. To this end, the problem for the construction of roads and bridges, the officer must be given sufficient attention.

1 bridge cracks
Cracks in roads and bridges will not only affect the appearance and structure of normal use, and will weaken the structural strength and stiffness of the bridge, thus leading to accidents. Our main materials used in road construction is concrete, and cracks in concrete structures currently on the road technical problems in the construction of a universal, which in addition to the reasons for poor quality of raw materials of concrete bridges, and partly because there is no reasonable construction workers caused by the use of concrete, such as: do not attach importance to the strength grade of concrete, the concrete exposure time is too long resulting in degeneration of the concrete damp; in the construction process of concrete mix did not meet regulatory requirements, not just by personal experience standard arbitrarily according to the ratio in the casting process of concrete vibrator concrete enough or too much strength; in concrete After removal of mold, does not give the necessary maintenance, leading to concrete cracking and other surface water there, for construction workers in the construction process should be routine for the calculation of concrete bridges. reinforced concrete structures in China provides maximum crack width of 0.2 to 0.3 mm. In addition, we calculated the temperature cracks, take insulation design, consider the location of the concrete structure, choose the concrete strength grade of concrete reinforcement ratio calculated using the appropriate model, from the material aspects of performance and structure take effective and comprehensive measures, combined with the reasonable construction process, according to the designed concrete strength requirements for construction, control the amount of cement and water-cement ratio, emphasis on concrete vibrator technology, calculate the removal time, use a certain amount of admixture and admixtures (for contraction and less impact on water heating, hot weather encountered in the use of well water mixing concrete, which can reduce the water temperature, although the bridge cracks in concrete structures is inevitable, but the construction workers should be based on crack causes the status quo and adopt a rational management approach to ensure completion of roads and bridges and beautiful shape and safe to use.

2 bridge steel corrosion
Life of steel is closely related with the life of the bridge, bridge corrosion of steel bars, then that would seriously endanger the life and safety of roads and bridges. Affecting steel corrosion by many factors, such as raw materials, environmental, construction, etc., as well as other states such as the steel stress and other factors can lead to reinforcement corrosion. bridge steel corrosion mechanism is very complex, roads and bridges, steel corrosion is a system which needs a lot of comprehensive measures. construction workers building roads and bridges in the process will strengthen the bridge steel protection awareness, to use of coated steel, this steel is low carbon steel surface with ordinary anti-corrosion coating to match the corrosive environment (acid rain, exhaust, de-icing agent to isolate, so that we can achieve the common purpose of low-carbon steel corrosion . coating material can not be destroyed, whether in transport, storage or during the installation process, this material is in poor condition has a certain durability and continuity in the life cycle of reinforced roads and bridges can maintain its structure and function In addition, the construction workers can also use the electrochemical corrosion protection method to prevent the bridge steel. This protection method has some technical content, is to make the steel to carry a sufficient number of extra electrons, so no matter how corrosive liquid hardness, steel will not corrosion, always in a stable condition for corrosion of the steel has to actively fix: removed all occurrences of the corrosion area of ​​concrete, sand blasting method to get rid of rust, according to the actual situation in order to increase the number of steel beams to ensure that the body tendons containing the amount. The last point to be emphasized that the construction workers to strengthen the bridge steel corrosion at the same time pay attention to the actual situation with the local combination of roads and bridges, according to the political and economic status, climatic conditions, geographic location, etc. of bridges classification, according to the classification of screening meet requirements, the economic rationality of the anti-corrosion material. Links to free download http://www.hi138.com
3 loose off the bridge pavement
Although the bridge pavement of the bridge is not a large share of the volume, but its road traffic running smoothly is very important in the succession exposed in the quality of roads and bridges, bridges, pavement quality by a certain attention in a number of bridge construction, bridge pavement construction quality is often negligence, strict control of construction processes, focus only on the superficial, on the issue of quality in appearance, resulting in premature bridge deck pavement cracks, loose , loss and other issues, maintenance cycles are getting shorter. on the bridge pavement structure is rigid in structure, present, and the overloading of heavy traffic is becoming worse, pavement layer directly bear the load of the impact of vehicles and pedestrians, The existing bridge pavement and heavy or super-rapid increase in the number of heavy vehicles have been incompatible, thus increasing the load on the bridge pavement, the construction workers in the construction of the bridge pavement layer in the process, should be taken to ensure the bridge pavement thickness of the pavement material should have good bending properties, which can weaken the pavement to avoid bending or cracking, pavement materials used to ensure there are no obvious during the cracking and other problems. ply waterproofing materials in the construction process should be sufficient attention to ensure that basic is not permeable paving, to prevent water infiltration caused by a variety of materials, water damage, thus shortening the life of the bridge pavement layer for non-frozen areas in the roads and bridges, the bridge pavement layer in waterproof concrete covered with a certain thickness (thickness up to 8 ~ 10cm, in the frozen region for possible cracks in roads and bridges, the paste can be covered with asphalt concrete or concrete, this concrete is flexible, can be effective in preventing the bridge shop loading layer cracks.

4 bridge construction is not high quality of personnel
China's road construction sites were located in high mountains and dense human Shaolin place, poor living conditions, transport facilities, which requires road construction workers work with a firm belief in hard real political quality, and establish wholeheartedly serving the people of life and values, so truly the way to home to road for the industry, peace of mind for our economic take-off and mountain roads to contribute to the development, but in real life, many construction workers are afraid of hardship, fear of involvement, professional quality is not high, the difficulties encountered little timid on the back, and some construction workers think of themselves as technical education, feel that they understand the technology, culture, more than enough problems to cope with current technology, this is a very wrong concept of construction workers to keep learn new knowledge, improve their literacy and ability. ① construction workers to continuously improve their professional skills, update their knowledge with the times, adapt to the social development requirements to make their own moment to remember that the present era of science and technology advances, useful knowledge today, tomorrow it may become obsolete, they have to keep learning in order to not be out of this society. ② construction workers to have more contact, learning management, law, networks and other aspects of knowledge, so that multi-skill in addition to know construction technology, but also familiar aesthetic, environmental, hydrogeological and other relevant knowledge, so as to create both beautiful and economical bridges. ③ construction personnel to be familiar with relevant laws, claims procedures, contract terms and other related knowledge, China has joined WTO and economic activities with international standards, construction workers must know how to safeguard the legal rights of the site, create compliant bridges and improve our market competitiveness.

5 Conclusion:
Road construction quality control is an important task, not only project participants to effort with a more adequate sense of responsibility required in the construction process to bridge the economic and rational use of material resources, adhere to the principles of construction, strict implementation of existing national construction norms and technical standards approved by the state to actively promote the use of "reliability of construction," "structural optimization of construction" and other modern construction methods, pay attention to local conditions, save construction funds, local materials, etc. This requires the construction workers and associated personnel learn experience, take all measures to avoid adverse factors to ensure the quality of the bridge in road construction projects to strengthen efforts to control the quality of construction, not only to ensure the quality of the project to ensure road safety, to extend the life of the road, but also to avoid rework or overhaul and economic losses to the country. Links to free download http://www.hi138.com