Discusses these measures in view of a series of jobs including concrete mixing, casting , vibrating, secondary trowelling , curing and secondary supporting.

In light of the characteristics of monsoon climate in certain district and through analyzing the appearing mechanism of antecedent concrete crack,the author solves the problem of antecedent crack in pumping concrete slab by quadric-plastering and integrative natural curing construction technique.

Through the study on engineering practice, this article proposes that secondary cement plastering can effi- cently control the surface cracks of cast-in-place concrete floorslab.

The manufacture time and cost can be sharply reduced by adopting two times punch shaping process with the aid of the mould of standard elliptical head.

Capacitor voltage transformer(CVT) contains capacitors and nonlinear inductances,so primary-side isolator operation may cause abnormal secondary voltage to influences normal operation of relay devices in substation,or even to lead misoperations of over-excitation protection for main transformers.

Using digital simulation,the mining-induced stress distribution in the entry with large mining height and second weight is analyzed,a optimum support scheme is choosed by perpendicular design.