Some people think that precast buildings use less time than traditional cast-in-situ buildings, which is only one thing.

frame column and shear wall); for the projects under drawing review, it shall be adjusted that there are no vertical load-bearing components submitted for review; for the projects that have passed the drawing review, it is also recommended to make design changes and cancel the use of Fabricated Form for vertical load-bearing components.

According to the field survey, precast buildings take more man hours than cast-in-situ structures, and the construction period is longer.

▲ according to the unreliable news, according to the requirements of XX Municipal Construction Commission, when all XX projects are submitted for drawing review, Vertical stressed members shall not be used in cast buildings (i.e.

If the quality of cast-in-situ structure is not good, it will also cause water seepage of external wall, but it is integral cast-in-situ after all, while the precast building has a large number of joints because it is the assembly of PC components.

It was analyzed that compared with the cast-in-place structure, the loss of water, electricity and formwork of precast buildings was reduced by 20% ~ 40%.

I don’t know how the seismic performance is? Do you have any friends who do research in this field to give you a brief introduction I very much agree with XXX’s opinion that assembly should not be a new topic, nor should there be too strong policy support and strong promotion measures.

Precast buildings have obvious advantages in four sections and one environmental protection.

Fourth, the assembly building leaves huge quality hidden dangers, such as water seepage from the outer wall.

If the PC factory has insufficient capacity, the construction site may have to wait in line, thus delaying the construction period.

Moreover, these joints also affect the mechanical properties of the structure..

Only by adjusting measures to local conditions and allowing the market to choose is the most correct path.

In order to change the mode of construction and production, transformation and upgrading, the construction industry also needs to have practical feasibility.

Secondly, domestic building components are not standardized, and various specifications are changeable, which is equal to personalized customization, mass production is not allowed, and the reuse rate is low, so it is impossible to reduce its marginal cost.

The authoritative civil expert team will build a civil bar and join the provincial and municipal communication group.

In fact, each splice is a weak point.

The reason is very clear: at present, the connection of vertical cast load-bearing system is immature, mainly manifested in mortar anchor link joints There is no effective testing method for the compactness of grouting materials at the site, and the grouting quality is mixed in the market.

The only advantage of precast buildings is to reduce on-site wet operation, and water and electricity may not be saved.

The parts and components of precast buildings can be processed in advance in the factory, but the installation of PC components takes more man hours.

There are the following factors restricting the development of assembly in China: first, the assembly technology at home and abroad is immature, and there are no skilled operators in this field.

U Bar Anchor

Everyone likes good things, and everyone just wants to cheat the government’s money for bad things.: At present, on-site control is indeed a problem: the biggest problem of precast concrete structure is the on-site inspection means.

So why are foreign precast buildings very successful? Because the foreign assembly technology is mature, the parts are standardized.

After investigation and research, the author found that precast buildings have little advantages over cast-in-place structures.

Any technology should do both feasibility study and non feasibility study.

In addition, PC installers on the construction site are newly added, which was not originally available.

After hearing this news, peers in the industry agreed: for the assembled type, I have been worried about the seismic problem.

At present, some local governments are pushing for precast buildings, and require the assembly rate and prefabrication rate in several rings to reach how many indicators.

In fact, it is unnecessary.

If a technology or process does not improve productivity, has no cost advantage, or even significantly increases cost, and the quality can not be guaranteed, then it has no promotion value.

▲ click the civil bar to pay attention to our civil bar.

Its quality depends too much on on-site operation.

If the joints are not handled well or cut corners, although there may be no problem within one or two years after completion, water seepage will certainly occur after three years, and the cost of future maintenance is quite high.

If only feasibility study is done, it may only see its advantages and ignore its disadvantages.

If the inspection means can’t keep up, no matter how good the laboratory system arrives at the site, we don’t know what it will look like.

The energy consumption of cast-in-situ concrete at the construction site is the same as that of factory prefabrication! But the promotion of precast concrete is under the banner of energy conservation and environmental protection! But the first problem that should be solved for the structure is safety.: there are still many differences in the control between the laboratory and the site.: what you have seen at the construction site should be the same Not very optimistic, hehe: The compactness check of grouting may be a problem: I feel like I’m assembling for the sake of assembling now! In fact, the assembly type of infilled wall is more reliable Mao Hongbin said in his wechat < wechat >: precast buildings may be a good thing, but not all good things are feasible.

Third, due to the lack of craftsmanship, migrant workers have been used to rough manufacturing, so they can’t adapt to and meet the accuracy requirements of precast buildings.

Some people think that the labor volume of precast buildings is significantly reduced by 30% ~ 50% compared with traditional cast-in-place buildings, so they come to the conclusion that the labor volume has obvious advantages.

The consciousness and self-discipline of construction workers cannot be tested in China’s construction projects Many frames in Japan are cast, The connection method is basically similar to ours (or we use it for modification), so it’s not a technical problem, but a management problem.: the energy consumption of concrete is mainly cement.

In fact, the total labor of precast buildings will not be reduced, and may still increase, but some of the workers required for reinforcement works, woodworking formwork and concrete pouring originally constructed on site have been transferred to the precast component processing plant.