How Bacteria Build Stronger Concrete

细菌如何建造更坚固的混凝土

课文音频

可先听下面的整段朗读；需要逐句点读时，请打开阅读器，体验会更顺手。

课文

Traditional concrete cracks easily under stress, letting water and rust damage steel reinforcements.

传统混凝土受力易开裂，导致水分渗入并锈蚀钢筋。
Scientists discovered certain soil bacteria, like Bacillus pasteurii, can produce limestone naturally.

科学家发现某些土壤细菌（如巴氏芽孢杆菌）能天然生成石灰石。
When mixed into concrete with calcium lactate and oxygen, these microbes ‘breathe’ and mineralize.

将这些微生物与乳酸钙和氧气混入混凝土后，它们会‘呼吸’并矿化。
Their metabolic activity forms tiny calcium carbonate crystals inside micro-cracks.

其代谢活动在微裂缝内形成微小的碳酸钙晶体。
This self-healing process seals gaps up to 0.5 mm wide within three weeks.

这种自修复过程可在三周内封堵宽度达0.5毫米的裂缝。
The repaired concrete regains up to 90% of its original strength without human intervention.

修复后的混凝土无需人工干预即可恢复至原始强度的90%。
Unlike polymer additives, bacterial healing works repeatedly as new cracks appear.

与聚合物添加剂不同，细菌修复可随新裂缝反复发生。
Field trials show bridges and tunnels using this bio-concrete last 20–30% longer.

实地试验表明，采用这种生物混凝土的桥梁和隧道寿命延长20%–30%。
It also cuts long-term maintenance costs and reduces CO₂ emissions from repairs.

它还能降低长期维护成本，并减少维修产生的二氧化碳排放。
Here, microbiology meets civil engineering in a quietly revolutionary way.

在这里，微生物学与土木工程以一种静默而革命性的方式交汇。