不易风化的

Efflorescence on new brickwork may be unsightly, but is unlikely to cause damage.

不易发现新铺砌的墙面上的风化痕迹，几乎没有损害。

Concrete because its draw materials is extensive, the price is low, compressive strength is high, but pouring into all sorts of appearance, and be able to bear or endure bad temper is good, not easy and efflorescent, upkeep costs is low, one of the most extensive housing materials are used in becoming current world to build a structure.

混凝土因其取材广泛，价格低廉，抗压强度高，可浇注成各种外形，并且耐火性好，不易风化，养护费用低，成为当今世界建筑结构中使用最广泛的建筑材料之一。

It is embodied concretely:(1) With the adoption of grouting bolts, the cranny in wall rocks can be blocked up, the air can be isolated, the wall rocks can be prevented to be weatherized and make water, the strength of wall rocks can also be avoided to be lowered;(2) The lax broken wall rocks are commentated to a whole by liquid after they were grouted and the rock"s strength is increased, so the wall rocks become a part of the support structure by using itself and become a whole with the original rock, and the roadway is made to keep stable but not easy to be broken;(3) The spray layer wall are filled with liquid after grouting, the stress is avoided to be concentrated because the load could be evenly acted on the spray layer and the support;(4) The pressure acted on the plank can be delivered to the two sidepieces and then to the bottom by reinforcing the sidepiece; At the same time, the concentration degree of loads acted on the motherboard can be weaken because of the enlargement of the combination arch"s thickness, as result, the rock"s stress is lowered and the heaving is alleviated;(5) The common bolt is made to be fixed the whole length after grouting, the layers are connected to a integral whole and bear the weight of loads, so the support structure"s unity is increased.

具体体现在：(1)采用注浆锚杆注浆，可以利用浆液封堵围岩裂隙，隔绝空气，防止围岩风化，且能防止淋水和渗水，避免围岩被水浸湿而降低围岩的本身强度及造成的巷道变形。(2)注浆后浆液将松散破碎的围岩胶结成整体，提高了岩体强度，实现利用围岩本身作为支护结构的一部分，且与原岩形成一个整体，使巷道保持稳定而不易产生破坏；(3)注浆后使得喷层壁后充填密实，保证荷载能均匀地作用在喷层和支护上，避免出现应力集中点而首先破坏；(4)注浆后使作用在顶板上的压力能有效地传递到两帮，通过对帮的加固，又能把荷载传递到底板；同时由于组合拱厚度的加大，这样又能减小作用在底板上的荷载集中度，从而减小底板岩石中的应力，减轻底臌；(5)注浆加固后能使普通端锚锚杆实现全长锚固，它们共同将多层组合拱连成一体，共同承载，提高了支护结构的整体性。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。