2.7 Do good well at backfill

Water-proof architectural backfill is a final working procedure , it be sometimes ignored , this is a very big faults in fact under the ground.When the water-proof structure job is over queen responds to the construction carrying out backfill immediately.Most important ,we  should take backfill seriously self mass; Secondly, backfill varia and ponding should clear up the pit bottom in the front , respond to densification with layers when backfill. Water-proof structure vicinity layer pounds true backfill , self is a reliable and economical as well water proofing drapery under the ground. In project basement engineering construction Shanghai,since organizing water proofing down to earth strictly with all above seven passes, the concrete is under construction , effect is comparatively ideal.The percolating water phenomenon does not appear.

为了防止业主对混凝土工程的索赔,就必须做好施工过程中温度与裂缝控制。本文通过多年的现场观察，通过查阅有关混凝土内部应力方面的专著，对混凝土温度裂缝产生的原因、现场混凝土温度的控制和预防裂缝的措施进行等进行阐述。

1、引  言

混凝土在现代工程建设中占有重要地位,源|自&优尔-文*论/文\网[www.youerw.com。而在今天，混凝土的裂缝较为普遍，在桥梁工程中裂缝几乎无所不在。尽管我们在施工中采取各种措施，小心谨慎，但裂缝仍然时有出现。究其原因，我们对混凝土温度应力的变化注意不够是其中之一。

在大体积混凝土中，温度应力及温度控制具有重要意义。这主要是由于两方面的原因。首先，在施工中混凝土常常出现温度裂缝，影响到结构的整体性和耐久性。其次，在运转过程中，温度变化对结构的应力状态具有显著的不容忽视的影响。我们遇到的主要是施工中的温度裂缝，因此本文仅对施工中混凝土裂缝的成因和处理措施做一探讨。