It is a case of collocation. We consolidate knowledge but reinforce concrete. 'Reinforce' means to make something stronger by adding support, e.g. metal in concrete. 'Consolidate' has a similar meaning but is used in different situations; e.g. the company is consolidating it's position in the market (not 'reinforcing').

The answer to your question is definitely to reinforce. The difference between consolidation and reinforcement is this: Consolidation of any substance is the gathering of what is already present. To consolidate your concrete would be to gather up all of the concrete you have and move it to a single location. Reinforcement is the addition of things to what is already present. This would be adding metal to concrete in order to make the slabs more durable.

consolidate- combine (a number of things) into a single more effective or coherent whole. "all manufacturing activities have been consolidated in new premises" synonyms: combine, unite, merge, integrate, amalgamate, fuse, synthesize, bring together, unify "consolidate the results into an action plan" reinforce- verb verb: reinforce; 3rd person present: reinforces; past tense: reinforced; past participle: reinforced; gerund or present participle: reinforcing strengthen or support, especially with additional personnel or material. "paratroopers were sent to reinforce the troops already in the area" synonyms: augment, increase, add to, supplement, boost, top up "the need to reinforce NATO troops" strengthen (an existing feeling, idea, or habit). "various actions of the leaders so reinforced fears and suspicions that war became unavoidable" synonyms: strengthen, fortify, support; More cement, boost, promote, encourage, deepen, enrich, enhance, intensify, improve This depends on the contextual use of the word because you can consolidate concrete with other materials that may not make the concrete stronger. the use of the word stronger gives the sentence the hint that you are trying to make the concrete tougher by reinforcing the concrete with a strong material like metal.